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Sample records for superior imaging characteristics

  1. Superior intellectual ability in schizophrenia: neuropsychological characteristics.

    Science.gov (United States)

    MacCabe, James H; Brébion, Gildas; Reichenberg, Abraham; Ganguly, Taposhri; McKenna, Peter J; Murray, Robin M; David, Anthony S

    2012-03-01

    It has been suggested that neurocognitive impairment is a core deficit in schizophrenia. However, it appears that some patients with schizophrenia have intelligence quotients (IQs) in the superior range. In this study, we sought out schizophrenia patients with an estimated premorbid Intelligence Quotient (IQ) of at least 115 and studied their neuropsychological profile. Thirty-four patients meeting diagnostic criteria for schizophrenia or schizoaffective disorder, as defined by the Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV), with mean estimated premorbid IQ of 120, were recruited and divided into two subgroups, according to whether or not their IQ had declined by at least 10 points from their premorbid estimate. Their performance on an extensive neuropsychological battery was compared with that of 19 IQ-matched healthy controls and a group of 16 "typical" schizophrenia patients with estimated premorbid IQ Schizophrenia patients whose estimated premorbid and current IQ both lay in the superior range were statistically indistinguishable from IQ-matched healthy controls on all neurocognitive tests. However, their profile of relative performance in subtests was similar to that of typical schizophrenia patients. Patients with superior premorbid IQ and evidence of intellectual deterioration had intermediate scores. Our results confirm the existence of patients meeting DSM-IV diagnostic criteria for schizophrenia who have markedly superior premorbid intellectual level and appear to be free of gross neuropsychological deficits. We discuss the implications of these findings for the primacy of cognitive deficits in schizophrenia.

  2. Magnetic resonance imaging evaluation of meniscoid superior labrum: normal variant or superior labral tear

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    Marcelo Novelino Simão

    Full Text Available Abstract Objective: The objective of this study was to determine the incidence of a "meniscoid" superior labrum. Materials and Methods: This was a retrospective analysis of 582 magnetic resonance imaging examinations of shoulders. Of those 582 examinations, 110 were excluded, for a variety of reasons, and the final analysis therefore included 472 cases. Consensus readings were performed by three musculoskeletal radiologists using specific criteria to diagnose meniscoid labra. Results: A meniscoid superior labrum was identified in 48 (10.2% of the 472 cases evaluated. Arthroscopic proof was available in 21 cases (43.8%. In 10 (47.6% of those 21 cases, the operative report did not include the mention a superior labral tear, thus suggesting the presence of a meniscoid labrum. In only one of those cases were there specific comments about a mobile superior labrum (i.e., meniscoid labrum. In the remaining 11 (52.4%, surgical correlation demonstrated superior labral tears. Conclusion: A meniscoid superior labrum is not an infrequent finding. Depending upon assumptions and the requirement of surgical proof, the prevalence of a meniscoid superior labrum in this study was between 2.1% (surgically proven and 4.8% (projected. However, superior labral tears are just as common and are often confused with meniscoid labra.

  3. Origins of Superior Dynamic Visual Acuity in Baseball Players: Superior Eye Movements or Superior Image Processing

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    Uchida, Yusuke; Kudoh, Daisuke; Murakami, Akira; Honda, Masaaki; Kitazawa, Shigeru

    2012-01-01

    Dynamic visual acuity (DVA) is defined as the ability to discriminate the fine parts of a moving object. DVA is generally better in athletes than in non-athletes, and the better DVA of athletes has been attributed to a better ability to track moving objects. In the present study, we hypothesized that the better DVA of athletes is partly derived from better perception of moving images on the retina through some kind of perceptual learning. To test this hypothesis, we quantitatively measured DV...

  4. Origins of superior dynamic visual acuity in baseball players: superior eye movements or superior image processing.

    Directory of Open Access Journals (Sweden)

    Yusuke Uchida

    Full Text Available Dynamic visual acuity (DVA is defined as the ability to discriminate the fine parts of a moving object. DVA is generally better in athletes than in non-athletes, and the better DVA of athletes has been attributed to a better ability to track moving objects. In the present study, we hypothesized that the better DVA of athletes is partly derived from better perception of moving images on the retina through some kind of perceptual learning. To test this hypothesis, we quantitatively measured DVA in baseball players and non-athletes using moving Landolt rings in two conditions. In the first experiment, the participants were allowed to move their eyes (free-eye-movement conditions, whereas in the second they were required to fixate on a fixation target (fixation conditions. The athletes displayed significantly better DVA than the non-athletes in the free-eye-movement conditions. However, there was no significant difference between the groups in the fixation conditions. These results suggest that the better DVA of athletes is primarily due to an improved ability to track moving targets with their eyes, rather than to improved perception of moving images on the retina.

  5. Origins of superior dynamic visual acuity in baseball players: superior eye movements or superior image processing.

    Science.gov (United States)

    Uchida, Yusuke; Kudoh, Daisuke; Murakami, Akira; Honda, Masaaki; Kitazawa, Shigeru

    2012-01-01

    Dynamic visual acuity (DVA) is defined as the ability to discriminate the fine parts of a moving object. DVA is generally better in athletes than in non-athletes, and the better DVA of athletes has been attributed to a better ability to track moving objects. In the present study, we hypothesized that the better DVA of athletes is partly derived from better perception of moving images on the retina through some kind of perceptual learning. To test this hypothesis, we quantitatively measured DVA in baseball players and non-athletes using moving Landolt rings in two conditions. In the first experiment, the participants were allowed to move their eyes (free-eye-movement conditions), whereas in the second they were required to fixate on a fixation target (fixation conditions). The athletes displayed significantly better DVA than the non-athletes in the free-eye-movement conditions. However, there was no significant difference between the groups in the fixation conditions. These results suggest that the better DVA of athletes is primarily due to an improved ability to track moving targets with their eyes, rather than to improved perception of moving images on the retina.

  6. Computed tomography imaging for superior semicircular canal dehiscence syndrome

    International Nuclear Information System (INIS)

    Dobeli, Karen

    2006-01-01

    Superior semicircular canal dehiscence is a newly described syndrome of sound and/or pressure induced vertigo. Computed tomography (CT) imaging plays an important role in confirmation of a defect in the bone overlying the canal. A high resolution CT technique utilising 0.5 mm or thinner slices and multi-planar reconstructions parallel to the superior semicircular canal is required. Placement of a histogram over a suspected defect can assist CT diagnosis

  7. Total variation superiorized conjugate gradient method for image reconstruction

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    Zibetti, Marcelo V. W.; Lin, Chuan; Herman, Gabor T.

    2018-03-01

    The conjugate gradient (CG) method is commonly used for the relatively-rapid solution of least squares problems. In image reconstruction, the problem can be ill-posed and also contaminated by noise; due to this, approaches such as regularization should be utilized. Total variation (TV) is a useful regularization penalty, frequently utilized in image reconstruction for generating images with sharp edges. When a non-quadratic norm is selected for regularization, as is the case for TV, then it is no longer possible to use CG. Non-linear CG is an alternative, but it does not share the efficiency that CG shows with least squares and methods such as fast iterative shrinkage-thresholding algorithms (FISTA) are preferred for problems with TV norm. A different approach to including prior information is superiorization. In this paper it is shown that the conjugate gradient method can be superiorized. Five different CG variants are proposed, including preconditioned CG. The CG methods superiorized by the total variation norm are presented and their performance in image reconstruction is demonstrated. It is illustrated that some of the proposed variants of the superiorized CG method can produce reconstructions of superior quality to those produced by FISTA and in less computational time, due to the speed of the original CG for least squares problems. In the Appendix we examine the behavior of one of the superiorized CG methods (we call it S-CG); one of its input parameters is a positive number ɛ. It is proved that, for any given ɛ that is greater than the half-squared-residual for the least squares solution, S-CG terminates in a finite number of steps with an output for which the half-squared-residual is less than or equal to ɛ. Importantly, it is also the case that the output will have a lower value of TV than what would be provided by unsuperiorized CG for the same value ɛ of the half-squared residual.

  8. Magnetic resonance imaging in congenital superior oblique palsy

    International Nuclear Information System (INIS)

    Sato, Miho; Kondo, Nagako; Awaya, Shinobu; Nomura, Hideki; Yagasaki, Teiji.

    1996-01-01

    MRI examinations were carried out on the defined congenital superior oblique palsy in order to distinguish the congenital and acquired palsies. Subjects were 19 patients diagnosed as congenital and their MRI images of 3 or 5 mm-thick coronary slice were taken. The volume of the oblique muscle was calculated from the images and a comparison was made between the diseased and healthy normal sides. The oblique muscle volume at the diseased side was found reduced in most of congenital superior oblique palsy patients. The reduction was observed even at childhood and was thus considered to be a malformation. Further, it is conceivable that the palsy could be caused by the abnormality in the central nervous system as well as by the present anatomical abnormality. (K.H.)

  9. Abdominal vascular syndromes: characteristic imaging findings

    International Nuclear Information System (INIS)

    Cardarelli-Leite, Leandro; Velloni, Fernanda Garozzo; Salvadori, Priscila Silveira; Lemos, Marcelo Delboni; D'Ippolito, Giuseppe

    2016-01-01

    Abdominal vascular syndromes are rare diseases. Although such syndromes vary widely in terms of symptoms and etiologies, certain imaging findings are characteristic. Depending on their etiology, they can be categorized as congenital - including blue rubber bleb nevus syndrome, Klippel-Trenaunay syndrome, and hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber syndrome) - compressive - including 'nutcracker' syndrome, median arcuate ligament syndrome, Cockett syndrome (also known as May-Thurner syndrome), and superior mesenteric artery syndrome. In this article, we aimed to illustrate imaging findings that are characteristic of these syndromes, through studies conducted at our institution, as well as to perform a brief review of the literature on this topic. (author)

  10. Abdominal vascular syndromes: characteristic imaging findings

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    Cardarelli-Leite, Leandro; Velloni, Fernanda Garozzo; Salvadori, Priscila Silveira; Lemos, Marcelo Delboni; D' Ippolito, Giuseppe, E-mail: leandrocleite@gmail.com [Universidade Federal de Sao Paulo (EPM/UNIFESP), Sao Paulo, SP (Brazil). Escola Paulista de Mediciana. Departmento de Diagnostico por Imagem

    2016-07-15

    Abdominal vascular syndromes are rare diseases. Although such syndromes vary widely in terms of symptoms and etiologies, certain imaging findings are characteristic. Depending on their etiology, they can be categorized as congenital - including blue rubber bleb nevus syndrome, Klippel-Trenaunay syndrome, and hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber syndrome) - compressive - including 'nutcracker' syndrome, median arcuate ligament syndrome, Cockett syndrome (also known as May-Thurner syndrome), and superior mesenteric artery syndrome. In this article, we aimed to illustrate imaging findings that are characteristic of these syndromes, through studies conducted at our institution, as well as to perform a brief review of the literature on this topic. (author)

  11. Persistent left superior vena cava with absent right superior vena cava: image findings

    International Nuclear Information System (INIS)

    Araujo Junior, Cyrillo Rodrigues de; Carvalho, Tarcisio Nunes; Fraguas Filho, Sergio Roberto; Costa, Marlos Augusto Bitencourt; Jacob, Beatriz Mahmud; Machado, Marcio Martins; Teixeira, Kim-Ir-Sen Santos; Ximenes, Carlos Alberto

    2003-01-01

    Persistent left superior vena cava absent right superior vena cava is a rare anomaly, with less than 150 cases reported in the literature. Congenitally persistent left superior vena cava is the most common variant of systemic venous return to the heart, resulting embryologically from failure of the left anterior cardinal vein to become obliterated. Its incidence varies from 0.3% in patients with otherwise normal heart to 4.3% in patients with congenital heart disease. In the majority of the patients, a right superior vena cava is present as well, but rarely the right anterior cardinal vein degenerates resulting in the absence of the normal right superior vena cava. The blood from the right side is carried by the persistent left superior vena cava to the right atrium through the coronary sinus. We report the case of a patient with a persistent left superior vena cava and absence of right superior vena cava identified by chance during a chest radiograph and computed tomography examination for investigation of chronic pulmonary obstructive disease. The patient had no congenital heart disease and the blood from the right side was drained by the persistent left superior vena cava into the right atrium through the coronary sinus. (author)

  12. Characteristics of image converters and image intensifiers

    International Nuclear Information System (INIS)

    Gurvich, A.M.; Shamanov, A.A.; Rozenberg, A.M.; Fajnberg, V.S.; Kavtorova, V.P.; Salyuk, L.V.; Yakovleva, F.B.

    1978-01-01

    The characteristics of image converters and image intensifiers, which determine the range of the X-radiation dose rates used and the image quality, are considered. The equations for calculating the requirements to be imposed on the separate intensifier elements from known parameters of other elements with an allowance for the nonlinearity of the television system and the role of fluctuation in the space distribution of X-radiation quanta are given

  13. Image characteristics of adrenal ganglioneuroma

    International Nuclear Information System (INIS)

    Ohishi, Yukihiko; Machida, Toyohei; Tashiro, Kazuya

    1994-01-01

    The image characteristics of adrenal ganglioneuroma observed in various types of imaging were examined. The subjects of the study were 6 cases of adrenal ganglioneuroma which had been histologically confirmed: the ages of the subjects ranged from 25 to 54 (mean age 41), and the maximum diameter of the tumors were 4 to 7 cm. The diagnostic methods employed in their detection were ultrasonography (US) and computed tomography (CT) in all 6 cases, magnetic resonance imaging (MRI) in 5 cases, and arteriography in 3 cases. On US and CT images, all 6 tumors had clear and smooth boundaries, and were homogeneous. They were hypoechoic on US images and low density on CT images. Of the 5 cases for which contrast CT images had been obtained, one showed a slightly heterogeneous staining. On MRI, the tumors were of lower intensity in comparison to the liver in 4 of 5 cases on the T 1 -weighted images, and the internal structure was homogeneous in 3 cases and heterogeneous in one case. The remaining one case was of isointensity and homogeneous. On the T 2 -weighted images, all 5 cases were of high intensity and heterogeneous. The blood flow distribution in the 3 tumors which were examined by Gd-DTPA dynamic MRI was low and of isointensity to the liver: 2 were heterogeneous and one was homogeneous. T 1 -enhanced images were obtained in 4 cases: 2 were of high intensity and heterogeneous, one was of isointensity and homogeneous, and one was of heterogeneously isointensity. Arteriography indicated that all 3 cases were hypovascular and no vascularization or ruptures were evident. It appeared that the imaging characteristics of adrenal ganglioneuroma were as follows: (1) homogeneous on US and CT images; (2) hypoechoic on US images, low density on CT images and little enhancement on contrast CT images; (3) of low intensity homogeneous on T 1 -weighted images and of high intensity heterogeneous on T 2 -weighted images and little blood flow distribution on dynamic MRI. (author)

  14. Superiority of CT imaging reconstruction on Linux OS

    International Nuclear Information System (INIS)

    Lin Shaochun; Yan Xufeng; Wu Tengfang; Luo Xiaomei; Cai Huasong

    2010-01-01

    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)

  15. Superior MR images with electronically tuned and decoupled surface coils

    International Nuclear Information System (INIS)

    Ingwersen, H.; Freisen, L.; Friedrich, A.; Kess, H.; Krause, N.; Meissner, R.; Popp, W.

    1987-01-01

    In order to gain free positioning of surface coils in linearly polarized transmitting coils, it is absolutely necessary to electronically decouple both coils. For circularly polarized transmitting coils, decoupling is necessary in any case. In addition to the decoupling circuit automatic electronic tuning of the surface coils is used to gain the bast ratio of signal to noise. This combination of electronically decoupling and tuning of the surface coils yields intrinsic patient safety concerning local power deposition as well as free positioning and easy handling at the same time. Block diagrams, circuit schemes, and MR images obtained with several different surface coils are shown

  16. Imaging Characteristics of Venous Parenchymal Abnormalities.

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    Arnoux, Audrey; Triquenot-Bagan, Aude; Andriuta, Daniela; Wallon, David; Guegan-Massardier, Evelyne; Leclercq, Claire; Martinaud, Olivier; Castier-Amouyel, Mélody; Godefroy, Olivier; Bugnicourt, Jean-Marc

    2017-12-01

    There are few published data on the patterns of parenchymal imaging abnormalities in a context of cerebral venous thrombosis (CVT). The objectives of the present study were to describe the patterns of parenchymal lesions associated with CVT and to determine the lesion sites. We included 44 consecutively hospitalized patients with CVT and parenchymal lesions on magnetic resonance imaging. The diagnosis of CVT had been confirmed by magnetic resonance imaging/magnetic resonance venography. Magnetic resonance imaging patterns for CVT were retrospectively analyzed with regard to the lesion's type, shape, and site. The most frequent stroke subtype was hemorrhagic ischemia (in 56.8% of cases), followed by intracerebral hematoma (in 22.72% of cases) and nonhemorrhagic ischemia (in 20.45% of cases). Although there were no significant differences between these 3 groups with regard to the clinical and radiological characteristics, we observed a nonsignificant trend ( P =0.08) toward a shorter time interval between hospital admission and magnetic resonance imaging for nonhemorrhagic stroke. The CVT parenchymal abnormalities were centered on 6 main foci and were related to the site of venous occlusion: (1) the inferior parietal lobule (n=20; 44.5%), associated mainly with occlusion of the transverse sinus (n=10) or pure cortical veins (n=10); (2) the inferior and posterior temporal regions (n=10; 22.75%), associated mainly with occlusion of the transverse sinus (n=9); (3) the parasagittal frontal region (n=6; 13.6%), associated mainly with occlusion of the superior sagittal sinus (n=4) or the transverse sinus (n=4); (4) the thalamus (n=5; 11.3%) associated with occlusion of the straight sinus (n=5); (5) the cerebellar hemisphere (n=2; 4.5%), associated in both cases with occlusion of the transverse sinus; and (6) the deep hemispheric regions (n=3; 6.8%), associated with occlusion of the superior sagittal sinus in all cases. Parenchymal lesions caused by CVT display specific

  17. Superior Cervical Sympathetic Ganglion: Normal Imaging Appearance on 3T-MRI

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    Lee, Joo Yeon; Lee, Jeong Hyun [Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505 (Korea, Republic of); Song, Joon Seon; Song, Min Jeong [Department of Pathology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505 (Korea, Republic of); Hwang, Seung-Jun [Department of Anatomy and Cell Biology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505 (Korea, Republic of); Yoon, Ra Gyoung [Department of Radiology, Catholic Kwandong University International St. Mary' s Hospital, Catholic Kwandong University College of Medicine, Incheon 22711 (Korea, Republic of); Jang, Seung Won; Park, Ji Eun [Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505 (Korea, Republic of); Heo, Young Jin [Department of Radiology, Busan Paik Hospital, Inje University College of Medicine, Busan 47392 (Korea, Republic of); Choi, Young Jun; Baek, Jung Hwan [Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505 (Korea, Republic of)

    2016-11-01

    To identify superior cervical sympathetic ganglion (SCSG) and describe their characteristic MR appearance using 3T-MRI. In this prospective study, we recruited 53 consecutive patients without history of head and neck irradiation. Using anatomic location based on literature review, both sides of the neck were evaluated to identify SCSGs in consensus. SCSGs were divided into definite (medial to internal carotid artery [ICA] and lateral to longus capitis muscle [LCM]) and probable SCSGs based on relative location to ICA and LCM. Two readers evaluated signal characteristics including intraganglionic hypointensity of all SCSGs and relative location of probable SCSGs. Interrater and intrarater agreements were quantified using unweighted kappa. Ninety-one neck sites in 53 patients were evaluated after exclusion of 15 neck sites with pathology. Definite SCSGs were identified at 66 (73%) sites, and probable SCSGs were found in 25 (27%). Probable SCSGs were located anterior to LCM in 16 (18%), lateral to ICA in 6 (7%), and posterior to ICA in 3 (3%). Intraganglionic hypointensity was identified in 82 (90%) on contrast-enhanced fat-suppressed T1-weighted images. There was no statistical difference in the relative location between definite and probable SCSGs of the right and left sides with intragnalionic hypointensity on difference pulse sequences. Interrater and intrarater agreements on the location and intraganglionic hypointensity were excellent (κ-value, 0.749–1.000). 3T-MRI identified definite SCSGs at 73% of neck sites and varied location of the remaining SCSGs. Intraganglionic hypointensity was a characteristic feature of SCSGs.

  18. Superior cervical sympathetic ganglion: Normal imaging appearance on 3T-MRI

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    Lee, Joo Yeon; Lee, Jeong Hyun; Song, Joon Seon [Dept. of Radiology, and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of); and others

    2016-09-15

    To identify superior cervical sympathetic ganglion (SCSG) and describe their characteristic MR appearance using 3T-MRI. In this prospective study, we recruited 53 consecutive patients without history of head and neck irradiation. Using anatomic location based on literature review, both sides of the neck were evaluated to identify SCSGs in consensus. SCSGs were divided into definite (medial to internal carotid artery [ICA] and lateral to longus capitis muscle [LCM]) and probable SCSGs based on relative location to ICA and LCM. Two readers evaluated signal characteristics including intraganglionic hypointensity of all SCSGs and relative location of probable SCSGs. Interrater and intrarater agreements were quantified using unweighted kappa. Ninety-one neck sites in 53 patients were evaluated after exclusion of 15 neck sites with pathology. Definite SCSGs were identified at 66 (73%) sites, and probable SCSGs were found in 25 (27%). Probable SCSGs were located anterior to LCM in 16 (18%), lateral to ICA in 6 (7%), and posterior to ICA in 3 (3%). Intraganglionic hypointensity was identified in 82 (90%) on contrast-enhanced fat-suppressed T1-weighted images. There was no statistical difference in the relative location between definite and probable SCSGs of the right and left sides with intragnalionic hypointensity on difference pulse sequences. Interrater and intrarater agreements on the location and intraganglionic hypointensity were excellent (κ-value, 0.749–1.000). 3T-MRI identified definite SCSGs at 73% of neck sites and varied location of the remaining SCSGs. Intraganglionic hypointensity was a characteristic feature of SCSGs.

  19. Some Numerical Characteristics of Image Texture

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    O. Samarina

    2012-05-01

    Full Text Available Texture classification is one of the basic images processing tasks. In this paper we present some numerical characteristics to the images analysis and processing. It can be used at the solving of images classification problems, their recognition, problems of remote sounding, biomedical images analysis, geological researches.

  20. Characteristics of superior soybean breeding lines tolerance to rust (Phakopsora pachyrhizi Syd.

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    Alfi Inayati

    2016-04-01

    Full Text Available Soybean rust caused by Phakopsora pachyrhizi is one of the most important diseases which limits soybean production. The aim of this study was to evaluate the resistance of 28 superior soybean lines and their tolerance to rust. The study was conducted at a screen house and arranged in a completely randomized design (CRD; three replications. All genotypes tested were artificially inoculated with P. pachyrhizi, and a set of un-inoculated genotypes was planted as a comparison. Number of pustules was recorded weekly, and resistant criteria was rated based on the International working group on soybean rust IWGSR method. Lesion color (LC, sporulation level (SL, number of uredia (NoU, frequency of pustule which had uredia, and yield were also recorded. Among 28 genotypes tested, only one was categorized as resistant and 2 genotypes were susceptible. Resistant genotypes had few pustules, lower AUDPC values, low disease severity, and Reddish Brown lesion type. Soybean rust affected yield components, i.e. number of intact pods and yield per plant. Yield loses due to rust in this study varied from 5-89%, and the average was 51%. The set of lines from Tanggamus pedigree showed more resistant to rust but less tolerant compared to Sinabung pedigree.How to CiteInayati, A., & Yusnawan, E. (2016. Characteristics of superior soybean breeding lines tolerancet to rust (Phakopsora pachyrhizi Syd.. Biosaintifika: Journal of Biology & Biology Education, 8(1, 47-55.

  1. Breast varices: imaging findings of an unusual presentation of collateral pathways in superior vena caval syndrome

    International Nuclear Information System (INIS)

    Oezdemir, Ayseguel; Ilgit, Erhan T.; Konus, Oeznur L.; Cetin, Meltem; Oezsunar, Yelda

    2000-01-01

    Imaging findings are presented of an unusual pathway of collateral circulation consisting of bilateral and diffuse dilated breast veins from a patient with long standing superior vena caval syndrome. The main importance of this case is the extent of the collateral development through the breast veins, serving as the major pathway of collateral circulation. Identification of this unusual collateral development, which resembles breast varices, was performed with contrast-enhanced chest CT scans, digital subtraction venography, color Doppler ultrasonography, and mammographic studies. Collateral development was secondary to a long segment idiopathic venous occlusion involving bilateral subclavian and brachiocephalic veins as well as vena cava superior. We conclude that dilated breast veins when detected on any imaging modality should raise the suspicion of central venous obstruction

  2. Measurements of image characteristics of DSA installations

    International Nuclear Information System (INIS)

    Busch, H.P.; Strauss, L.G.; Freimarck, R.D.

    1984-01-01

    Measurements for quantifying the image characteristics were carried out on three DSA installations (DVI 1 - Philips, Angiotron - Siemens and DF 3000 - General Eletric). Contrast resolution was measured with a vessel phantom (General Electric) and spatial resolution with a lead grid. A further parameter was the dose entering the image intensifier. The Angiotron was used with an intensifier with 53 cm. diameter and the DF 3000 with temporal subtraction of the video images and the subtraction of dual energy images (hybrid technique). These measurements can be carried out quickly and easily and are a step towards standardisation of measurements of image characteristics of DSA installations. (orig.) [de

  3. Fat saturation in dynamic breast MRI at 3 Tesla: is the Dixon technique superior to spectral fat saturation? A visual grading characteristics study

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    Clauser, P. [University of Udine, Azienda Ospedaliero-Universitaria ' ' S.Maria della Misericordia' ' , Institute of Diagnostic Radiology, Udine (Italy); Medical University of Vienna, Department of Biomedical Imaging and Image-guided interventions, Division of Molecular and Gender Imaging, Vienna (Austria); Pinker, K.; Helbich, T.H.; Kapetas, P.; Bernathova, M.; Baltzer, P.A.T. [Medical University of Vienna, Department of Biomedical Imaging and Image-guided interventions, Division of Molecular and Gender Imaging, Vienna (Austria)

    2014-09-15

    To intra-individually compare the diagnostic image quality of Dixon and spectral fat suppression at 3 T. Fifty consecutive patients (mean age 55.1 years) undergoing 3 T breast MRI were recruited for this prospective study. The image protocol included pre-contrast and delayed post-contrast spectral and Dixon fat-suppressed T1w series. Two independent blinded readers compared spectral and Dixon fat-suppressed series by evaluating six ordinal (1 worst to 5 best) image quality criteria (image quality, delineation of anatomical structures, fat suppression in the breast and axilla, lesion delineation and internal enhancement). Breast density and size were assessed. Data analysis included Spearman's rank correlation coefficient and visual grading characteristics (VGC) analysis. Four examinations were excluded; 48 examinations in 46 patients were evaluated. In VGC analysis, the Dixon technique was superior regarding image quality criteria analysed (P < 0.01). Smaller breast size and lower breast density were significantly (P < 0.01) correlated with impaired spectral fat suppression quality. No such correlation was identified for the Dixon technique, which showed reconstruction-based water-fat mixups leading to insufficient image quality in 20.8 %. The Dixon technique outperformed spectral fat suppression in all evaluated criteria (P < 0.01). Non-diagnostic examinations can be avoided by fat and water image reconstruction. The superior image quality of the Dixon technique can improve breast MRI interpretation. (orig.)

  4. Tuberous root characteristics of sweet potato clones using multivariate techniques for selection of superior genotypes

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    Jackson da Silva

    2018-01-01

    Full Text Available The objective of this study was to evaluate the tuberous root characteristics of sweet potato clones using multivariate techniques for selection of superior genotypes, the present research was carried out in the Experimental area of the Plant Genetic Breeding Sector of the Agrarian Sciences Center of the Federal University of Alagoas (SMGP/CECA/UFAL. Were evaluated 44 new clones originated from progenies of half-siblings and germanic siblings, in addition to the cultivar Sergipana Vermelha, in lines of 5 m in length, spacing 1.0 mx 0.5 m, totaling a total area of 5 m²/clone. The harvest was done at 120 days after planting the branches, in which the production of non-commercial tuberous roots (PRTNC was evaluated, production of commercial tuberous roots (PRTC, production of tuberous roots (PTRT, total number of tuberous roots (NTRT, average weight of commercial tuberous roots (PMRTC, predominant color of tuberous root skin (CPPERT and predominant color of the tuberosal root pulp (CPPORT. Descriptive statistics, correlation technique and principal component analysis were used. It was observed that clones 23, 36, 17 and 37 presented interesting agronomic characteristics, being recommended for the cultivation and in the analysis of main components, the variables PTRT and PRTC presented greater importance, reflecting that they discriminate the clones satisfactorily.

  5. Physico-chemical characteristics of shallot New-Superior Varieties (NSV) from Indonesia

    Science.gov (United States)

    Sukasih, E.; Setyadjit; Musadad, D.

    2018-01-01

    Shallot is one of the priority agricultural commodities to be developed in Indonesia to reduce import and to stabilize domestic supply. The efforts include the selection of varieties, seed technology, agronomy, handling and processing to extend the supply and added value. Indonesian Agency for Agricultural Research and Development (IAARD) has purified, cross-pollinated, selected and released new varieties called New Superior Varieties (NSV) to farmers. The purpose of this research was to investigate the characteristic of fresh shallot NSV by understanding its potential for raw material of processed product. A completely randomized design (CRD) of single factor of ten local varieties of shallot such as Cv. Sembrani, Cv. Kuning, Cv. Pancasona, Cv. Bima, Cv. Trisula, Cv. Pikatan, Cv. Katumi, Cv. Kramat-2, Cv. Mentes and Cv. Majalok of three replication was used to arrange the experiment. The results showed that shallot New Superior Varieties (NSV) were significant by effect the physico-chemical parameters, such as diameter, length, weight of both in main bulb and tiller bulb, fat total, carbohydrate, crude fiber, starch content, antioxidant capacity and quercetin. Of the ten varieties of shallot characterized, the largest bulbs are Cv. Sembrani i.e 5.30 ± 0.3g per bulb, the best red color for shallot peeled was Cv. Kuning. Furthermore Cv. Pancasona have the highest protein content of 4.23 ± 0.2%, Cv. Mentes have the highest functional properties of quercetin 1766.4 ± 134 ppm. Shallot varieties such as Cv. Sembrani, Cv. Bima, Cv. Kuning and Cv. Trisula suitable for use as fresh product. Shallot varieties such as Cv. Pikatan, Cv. Pancasona, Cv. Katumi and Cv. Kramat-2 are suitable as raw materials for processed products. Cv. Mentes and Cv. Majalok were potential for raw materials of functional food and pharmaceutical industries.

  6. Incidence of dehiscence of the bony roof of the superior semicircular canal by CT imaging

    International Nuclear Information System (INIS)

    Watanabe, Akira

    2003-01-01

    Dehiscence of the bony roof of the superior semicircular canal (SSCC) is rare, but it has been recognized by otologists since Minor et al first described superior canal dehiscence syndrome (SCDS). In this study, dehiscence of the bony roof of SSCC was incidentally detected in three patients with benign paroxysmal positional vertigo out of 49 serial patients with vertigo and dizziness by multi-slice computed tomography. Although detection of dehiscence of the SSCC by ultra-high-resolution CT imaging of the temporal bones has been required for a diagnosis of SCDS, this study showed that dehiscence of the bony roof of the SSCC can be an incidental finding and therefore is not specific for SCDS. (author)

  7. Imaging characteristics of hemophagocytic lymphohistiocytosis

    International Nuclear Information System (INIS)

    Fitzgerald, Nancy E.; MacClain, Kenneth L.

    2003-01-01

    Hemophagocytic lymphohistiocytosis (HLH) is a nonmalignant disorder of immune regulation, with overproduction of cytokines and diminished immune surveillance. Symptoms are nonspecific and may affect multiple organs, including the central nervous system. Neuroimaging findings have been described in case reports and small series; body imaging findings have not been described extensively. To summarize findings of the most frequently performed imaging studies of the brain, chest and abdomen in patients with HLH. Retrospective review of chest radiographs and CT, abdominal ultrasound and CT, brain CT and MRI, skeletal surveys, and autopsy data. Twenty-five patients were diagnosed and treated for HLH at our institution over an 11-year period; 15 patients (60%) died. Common chest radiograph findings included alveolar-interstitial opacities with pleural effusions, often with rapid evolution and resolution. Hepatosplenomegaly, gallbladder wall thickening, hyperechoic kidneys and ascites were common abdominal findings, which resolved after therapy in some cases. Brain-imaging studies revealed nonspecific periventricular white-matter abnormalities, brain-volume loss and enlargement of extra-axial fluid spaces. Three infant cases, one with intracranial hemorrhage, one with multiple pathologic rib fractures and one with diaphyseal periosteal reaction involving multiple long bones on skeletal survey, raised suspicion of child abuse at presentation. Abuse was not substantiated in any case. Clinicians and radiologists should be aware of the radiographic manifestations of HLH, which are nonspecific and overlap with infectious, inflammatory and neoplastic disorders. Findings in the chest (similar to acute respiratory distress syndrome) and abdomen may progress rapidly and then regress with institution of appropriate anti-HLH therapy. CNS findings may be progressive. In some infants, initial imaging findings may mimic nonaccidental trauma. (orig.)

  8. Imaging characteristics of hemophagocytic lymphohistiocytosis

    Energy Technology Data Exchange (ETDEWEB)

    Fitzgerald, Nancy E. [E. B. Singleton Department of Diagnostic Imaging, Texas Children' s Hospital, 6621 Fannin Street, MC 2-2521, TX 77030, Houston (United States); MacClain, Kenneth L. [Texas Children' s Cancer Center, 6701 Fannin, Suite 1510, TX 77030, Houston (United States)

    2003-06-01

    Hemophagocytic lymphohistiocytosis (HLH) is a nonmalignant disorder of immune regulation, with overproduction of cytokines and diminished immune surveillance. Symptoms are nonspecific and may affect multiple organs, including the central nervous system. Neuroimaging findings have been described in case reports and small series; body imaging findings have not been described extensively. To summarize findings of the most frequently performed imaging studies of the brain, chest and abdomen in patients with HLH. Retrospective review of chest radiographs and CT, abdominal ultrasound and CT, brain CT and MRI, skeletal surveys, and autopsy data. Twenty-five patients were diagnosed and treated for HLH at our institution over an 11-year period; 15 patients (60%) died. Common chest radiograph findings included alveolar-interstitial opacities with pleural effusions, often with rapid evolution and resolution. Hepatosplenomegaly, gallbladder wall thickening, hyperechoic kidneys and ascites were common abdominal findings, which resolved after therapy in some cases. Brain-imaging studies revealed nonspecific periventricular white-matter abnormalities, brain-volume loss and enlargement of extra-axial fluid spaces. Three infant cases, one with intracranial hemorrhage, one with multiple pathologic rib fractures and one with diaphyseal periosteal reaction involving multiple long bones on skeletal survey, raised suspicion of child abuse at presentation. Abuse was not substantiated in any case. Clinicians and radiologists should be aware of the radiographic manifestations of HLH, which are nonspecific and overlap with infectious, inflammatory and neoplastic disorders. Findings in the chest (similar to acute respiratory distress syndrome) and abdomen may progress rapidly and then regress with institution of appropriate anti-HLH therapy. CNS findings may be progressive. In some infants, initial imaging findings may mimic nonaccidental trauma. (orig.)

  9. Axial nonimaging characteristics of imaging lenses: discussion.

    Science.gov (United States)

    Siew, Ronian

    2016-05-01

    At observation planes away from the image plane, an imaging lens is a nonimaging optic. We examine the variation of axial irradiance with distance in image space and highlight the following little-known observation for discussion: On a per-unit-area basis, the position of the highest concentration in image space is generally not at the focal plane. This characteristic is contrary to common experience, and it offers an additional degree of freedom for the design of detection systems. Additionally, it would also apply to lenses with negative refractive index. The position of peak concentration and its irradiance is dependent upon the location and irradiance of the image. As such, this discussion also includes a close examination of expressions for image irradiance and explains how they are related to irradiance calculations beyond the image plane. This study is restricted to rotationally symmetric refractive imaging systems with incoherent extended Lambertian sources.

  10. Veia cava superior esquerda anômala com ausência de veia cava superior direita: achados de imagem Persistent left superior vena cava with absent right superior vena cava: image findings

    Directory of Open Access Journals (Sweden)

    Cyrillo Rodrigues de Araújo Júnior

    2003-10-01

    Full Text Available A persistência da veia cava superior esquerda com ausência da veia cava superior direita é uma anomalia rara, com menos de 150 casos descritos na literatura. A não-obliteração e regressão da veia cardinal anterior esquerda durante o desenvolvimento embriológico promove uma variação sistêmica de retorno venoso ao coração, com persistência da veia cava superior esquerda. Sua incidência varia de 0,3% em pacientes sem alterações cardíacas congênitas concomitantes a 4,3% naqueles com cardiopatias. Na maioria das vezes coexiste a veia cava superior direita, porém se houver regressão e degeneração da veia cardinal anterior direita, implicará a sua ausência e a drenagem venosa para o coração será feita pela veia cava superior esquerda ao átrio direito, através do seio coronariano. Mostramos um caso de um paciente submetido a radiografia de tórax e tomografia computadorizada para avaliação de doença pulmonar obstrutiva crônica, tendo como achado a persistência da veia cava superior esquerda com ausência da direita, sem qualquer cardiopatia associada e com a drenagem cardíaca sendo feita, através do seio coronariano, para o átrio direito.Persistent left superior vena cava with absent right superior vena cava is a rare anomaly, with less than 150 cases reported in the literature. Congenitally persistent left superior vena cava is the most common variant of systemic venous return to the heart, resulting embryologically from failure of the left anterior cardinal vein to become obliterated. Its incidence varies from 0.3% in patients with otherwise normal heart to 4.3% in patients with congenital heart disease. In the majority of the patients, a right superior vena cava is present as well, but rarely the right anterior cardinal vein degenerates resulting in the absence of the normal right superior vena cava. The blood from the right side is carried by the persistent left superior vena cava to the right atrium through the

  11. Superiorized algorithm for reconstruction of CT images from sparse-view and limited-angle polyenergetic data

    Science.gov (United States)

    Humphries, T.; Winn, J.; Faridani, A.

    2017-08-01

    Recent work in CT image reconstruction has seen increasing interest in the use of total variation (TV) and related penalties to regularize problems involving reconstruction from undersampled or incomplete data. Superiorization is a recently proposed heuristic which provides an automatic procedure to ‘superiorize’ an iterative image reconstruction algorithm with respect to a chosen objective function, such as TV. Under certain conditions, the superiorized algorithm is guaranteed to find a solution that is as satisfactory as any found by the original algorithm with respect to satisfying the constraints of the problem; this solution is also expected to be superior with respect to the chosen objective. Most work on superiorization has used reconstruction algorithms which assume a linear measurement model, which in the case of CT corresponds to data generated from a monoenergetic x-ray beam. Many CT systems generate x-rays from a polyenergetic spectrum, however, in which the measured data represent an integral of object attenuation over all energies in the spectrum. This inconsistency with the linear model produces the well-known beam hardening artifacts, which impair analysis of CT images. In this work we superiorize an iterative algorithm for reconstruction from polyenergetic data, using both TV and an anisotropic TV (ATV) penalty. We apply the superiorized algorithm in numerical phantom experiments modeling both sparse-view and limited-angle scenarios. In our experiments, the superiorized algorithm successfully finds solutions which are as constraints-compatible as those found by the original algorithm, with significantly reduced TV and ATV values. The superiorized algorithm thus produces images with greatly reduced sparse-view and limited angle artifacts, which are also largely free of the beam hardening artifacts that would be present if a superiorized version of a monoenergetic algorithm were used.

  12. Semiautomated volumetric response evaluation as an imaging biomarker in superior sulcus tumors

    International Nuclear Information System (INIS)

    Vos, C.G.; Paul, M.A.; Dahele, M.; Soernsen de Koste, J.R. van; Senan, S.; Bahce, I.; Smit, E.F.; Thunnissen, E.; Hartemink, K.J.

    2014-01-01

    Volumetric response to therapy has been suggested as a biomarker for patient-centered outcomes. The primary aim of this pilot study was to investigate whether the volumetric response to induction chemoradiotherapy was associated with pathological complete response (pCR) or survival in patients with superior sulcus tumors managed with trimodality therapy. The secondary aim was to evaluate a semiautomated method for serial volume assessment. In this retrospective study, treatment outcomes were obtained from a departmental database. The tumor was delineated on the computed tomography (CT) scan used for radiotherapy planning, which was typically performed during the first cycle of chemotherapy. These contours were transferred to the post-chemoradiotherapy diagnostic CT scan using deformable image registration (DIR) with/without manual editing. CT scans from 30 eligible patients were analyzed. Median follow-up was 51 months. Neither absolute nor relative reduction in tumor volume following chemoradiotherapy correlated with pCR or 2-year survival. The tumor volumes determined by DIR alone and DIR + manual editing correlated to a high degree (R 2 = 0.99, P < 0.01). Volumetric response to induction chemoradiotherapy was not correlated with pCR or survival in patients with superior sulcus tumors managed with trimodality therapy. DIR-based contour propagation merits further evaluation as a tool for serial volumetric assessment. (orig.)

  13. Subliminal food images compromise superior working memory performance in women with restricting anorexia nervosa.

    Science.gov (United States)

    Brooks, Samantha J; O'Daly, Owen G; Uher, Rudolf; Schiöth, Helgi B; Treasure, Janet; Campbell, Iain C

    2012-06-01

    Prefrontal cortex (PFC) is dysregulated in women with restricting anorexia nervosa (RAN). It is not known whether appetitive non-conscious stimuli bias cognitive responses in those with RAN. Thirteen women with RAN and 20 healthy controls (HC) completed a dorsolateral PFC (DLPFC) working memory task and an anterior cingulate cortex (ACC) conflict task, while masked subliminal food, aversive and neutral images were presented. During the DLPFC task, accuracy was higher in the RAN compared to the HC group, but superior performance was compromised when subliminal food stimuli were presented: errors positively correlated with self-reported trait anxiety in the RAN group. These effects were not observed in the ACC task. Appetitive activation is intact and anxiogenic in women with RAN, and non-consciously interacts with working memory processes associated with the DLPFC. This interaction mechanism may underlie cognitive inhibition of appetitive processes that are anxiety inducing, in people with AN. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Intracranial Infections: Clinical and Imaging Characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Foerster, B.R.; Thurnher, M.M.; Malani, P.N.; Petrou, M.; Carets-Zumelzu, F.; Sundgren, P.C. [Dept. of Radiology, and Divisions of Infectious Diseases and G eriatric Medicine, Dept. of Internal Medicine, Univ. of Michigan Medical Center, Ann Arbor, MI (United States)

    2007-10-15

    The radiologist plays a crucial role in identifying and narrowing the differential diagnosis of intracranial infections. A thorough understanding of the intracranial compartment anatomy and characteristic imaging findings of specific pathogens, as well incorporation of the clinical information, is essential to establish correct diagnosis. Specific types of infections have certain propensities for different anatomical regions within the brain. In addition, the imaging findings must be placed in the context of the clinical setting, particularly in immunocompromised and human immunodeficiency virus (HIV)-positive patients. This paper describes and depicts infections within the different compartments of the brain. Pathology-proven infectious cases are presented in both immunocompetent and immunocompromised patients, with a discussion of the characteristic findings of each pathogen. Magnetic resonance spectroscopy (MRS) characteristics for several infections are also discussed.

  15. Characteristics of neuronal lipofuscin in the superior temporal gyrus in Alzheimer's disease do not differ from non-diseased controls: a comparison with disease-related changes in the superior frontal gyrus.

    Science.gov (United States)

    Mountjoy, Christopher Q; Dowson, Jonathan H; Harrington, Charles; Cairns, Mary R; Wilton-Cox, Helen

    2005-05-01

    Neuronal lipofuscin characteristics in the superior temporal gyrus from 21 patients with Alzheimer's disease (AD) and from 18 age-matched non-diseased subjects were compared with previously reported findings from the superior frontal gyrus. A discriminant function analysis of lipofuscin characteristics in the superior temporal gyrus did not provide a significant predictive level for cases whose diagnoses were correctly classified (56.4%, P=0.63). In contrast, AD-related decrease in the number of smaller lipofuscin regions in the neurons of the frontal gyrus was confirmed, and the same analysis of lipofuscin characteristics in this region gave a significant predictive level for membership of the AD group of 86.6% (P<0.001). The findings indicate that changes in neuronal lipofuscin related to AD, which may reflect an increased rate of lipofuscin formation, show differences between neocortical regions. This study provides additional information on the distribution of neuropathological characteristics in AD.

  16. Imaging characteristics of primary cranial Ewing sarcoma

    International Nuclear Information System (INIS)

    Li, Wai-Yung; Saunders, Dawn E.; Brock, Penelope

    2005-01-01

    Ewing sarcoma accounts for 10-15% of all childhood malignant bone tumours and is second in prevalence to osteosarcoma. The skull bones are an unusual site of origin of primary Ewing sarcoma in children. Previous reports concentrate on the neurosurgical aspects and relatively good outcome compared to other bone tumours of the calvarium. Reported cases mainly describe the imaging characteristics on CT. To describe the MRI and CT features of primary cranial Ewing sarcoma. The neuroimaging of three cases of primary cranial Ewing sarcoma are reviewed. Our three cases show an extra-axial mass that is high attenuation on CT and low signal on T2-weighted MRI. Haemorrhagic components, dural extension and contrast enhancement are also characteristic features. CT attenuation and magnetic resonance signal characteristics reflect sheets of densely packed cells seen in Ewing sarcoma. (orig.)

  17. Unusual imaging characteristics of complicated hydatid disease

    Energy Technology Data Exchange (ETDEWEB)

    Turgut, Ahmet Tuncay [Department of Radiology, Ankara Training and Research Hospital, Ankara (Turkey)]. E-mail: ahmettuncayturgut@yahoo.com; Altin, Levent [Department of Radiology, Numune Training and Research Hospital, Ankara (Turkey); Topcu, Salih [Department of Thoracic Surgery, Faculty of Medicine, Kocaeli University, Izmit (Turkey); Kilicoglu, Buelent [Department of 4th General Surgery, Ankara Training and Research Hospital, Ankara (Turkey); Altinok, Tamer [Department of Thoracic Surgery, Meram Faculty of Medicine, Selcuk University, Konya (Turkey); Kaptanoglu, Erkan [Department of Neurosurgery, Numune Training and Research Hospital, Ankara (Turkey); Karademir, Alp [Department of Radiology, Numune Training and Research Hospital, Ankara (Turkey); Kosar, Ugur [Department of Radiology, Ankara Training and Research Hospital, Ankara (Turkey)

    2007-07-15

    Hydatid disease, a worldwide zoonosis, is caused by the larval stage of the Echinococcus tapeworm. Although the liver and the lungs are the most frequently involved organs in the body, hydatid cysts of other organs are unusual. Radiologically, they usually demonstrate typical imaging findings, but unusual imaging characteristics of complicated cyst of hydatid disease, associated with high morbidity and mortality, are rarely described in the literature. The purpose of this study is to review the general features of hydatidosis and to discuss atypical imaging characteristics of the complicated hydatid disease in the human, with an emphasis on structure and rupture of the cystic lesion as well as ultrasonography (USG), computed tomography (CT), and magnetic resonance imaging (MRI) features of the disease. In our study, the available literature and images of the cases with complicated hydatidosis involving liver, lung, brain, spine and orbit were reviewed retrospectively. In hydatid disease, there are many potential local and systemic complications due to secondary involvement in almost any anatomic location in humans. Radiologically, in addition to the presence of atypical findings such as perifocal edema, non-homogenous contrast enhancement, multiplicity or septations and calcification, various unusual manifestations due to rupture or infection of the cyst have been observed in our cases with complicated hydatid disease. To prevent subsequent acute catastrophic results and the development of recurrences in various organs, it should be kept in mind that complicated hydatid cysts can cause unusual USG, CT, and MRI findings, in addition to typical ones, in endemic areas. Therefore, familiarity with atypical radiological appearances of complicated hydatid disease may be valuable in making a correct diagnosis and treatment.

  18. Unusual imaging characteristics of complicated hydatid disease

    International Nuclear Information System (INIS)

    Turgut, Ahmet Tuncay; Altin, Levent; Topcu, Salih; Kilicoglu, Buelent; Altinok, Tamer; Kaptanoglu, Erkan; Karademir, Alp; Kosar, Ugur

    2007-01-01

    Hydatid disease, a worldwide zoonosis, is caused by the larval stage of the Echinococcus tapeworm. Although the liver and the lungs are the most frequently involved organs in the body, hydatid cysts of other organs are unusual. Radiologically, they usually demonstrate typical imaging findings, but unusual imaging characteristics of complicated cyst of hydatid disease, associated with high morbidity and mortality, are rarely described in the literature. The purpose of this study is to review the general features of hydatidosis and to discuss atypical imaging characteristics of the complicated hydatid disease in the human, with an emphasis on structure and rupture of the cystic lesion as well as ultrasonography (USG), computed tomography (CT), and magnetic resonance imaging (MRI) features of the disease. In our study, the available literature and images of the cases with complicated hydatidosis involving liver, lung, brain, spine and orbit were reviewed retrospectively. In hydatid disease, there are many potential local and systemic complications due to secondary involvement in almost any anatomic location in humans. Radiologically, in addition to the presence of atypical findings such as perifocal edema, non-homogenous contrast enhancement, multiplicity or septations and calcification, various unusual manifestations due to rupture or infection of the cyst have been observed in our cases with complicated hydatid disease. To prevent subsequent acute catastrophic results and the development of recurrences in various organs, it should be kept in mind that complicated hydatid cysts can cause unusual USG, CT, and MRI findings, in addition to typical ones, in endemic areas. Therefore, familiarity with atypical radiological appearances of complicated hydatid disease may be valuable in making a correct diagnosis and treatment

  19. Image Quality Characteristics of Handheld Display Devices for Medical Imaging

    Science.gov (United States)

    Yamazaki, Asumi; Liu, Peter; Cheng, Wei-Chung; Badano, Aldo

    2013-01-01

    Handheld devices such as mobile phones and tablet computers have become widespread with thousands of available software applications. Recently, handhelds are being proposed as part of medical imaging solutions, especially in emergency medicine, where immediate consultation is required. However, handheld devices differ significantly from medical workstation displays in terms of display characteristics. Moreover, the characteristics vary significantly among device types. We investigate the image quality characteristics of various handheld devices with respect to luminance response, spatial resolution, spatial noise, and reflectance. We show that the luminance characteristics of the handheld displays are different from those of workstation displays complying with grayscale standard target response suggesting that luminance calibration might be needed. Our results also demonstrate that the spatial characteristics of handhelds can surpass those of medical workstation displays particularly for recent generation devices. While a 5 mega-pixel monochrome workstation display has horizontal and vertical modulation transfer factors of 0.52 and 0.47 at the Nyquist frequency, the handheld displays released after 2011 can have values higher than 0.63 at the respective Nyquist frequencies. The noise power spectra for workstation displays are higher than 1.2×10−5 mm2 at 1 mm−1, while handheld displays have values lower than 3.7×10−6 mm2. Reflectance measurements on some of the handheld displays are consistent with measurements for workstation displays with, in some cases, low specular and diffuse reflectance coefficients. The variability of the characterization results among devices due to the different technological features indicates that image quality varies greatly among handheld display devices. PMID:24236113

  20. The optimal monochromatic spectral computed tomographic imaging plus adaptive statistical iterative reconstruction algorithm can improve the superior mesenteric vessel image quality

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Xiao-Ping; Zuo, Zi-Wei; Xu, Ying-Jin; Wang, Jia-Ning [CT/MRI room, Affiliated Hospital of Hebei University, Baoding, Hebei, 071000 (China); Liu, Huai-Jun, E-mail: hebeiliu@outlook.com [Department of Medical Imaging, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, 050000 (China); Liang, Guang-Lu [CT/MRI room, Affiliated Hospital of Hebei University, Baoding, Hebei, 071000 (China); Gao, Bu-Lang, E-mail: browngao@163.com [Department of Medical Research, Shijiazhuang First Hospital, Shijiazhuang, Hebei, 050011 (China)

    2017-04-15

    Objective: To investigate the effect of the optimal monochromatic spectral computed tomography (CT) plus adaptive statistical iterative reconstruction on the improvement of the image quality of the superior mesenteric artery and vein. Materials and methods: The gemstone spectral CT angiographic data of 25 patients were reconstructed in the following three groups: 70 KeV, the optimal monochromatic imaging, and the optimal monochromatic plus 40%iterative reconstruction mode. The CT value, image noises (IN), background CT value and noises, contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR) and image scores of the vessels and surrounding tissues were analyzed. Results: In the 70 KeV, the optimal monochromatic and the optimal monochromatic images plus 40% iterative reconstruction group, the mean scores of image quality were 3.86, 4.24 and 4.25 for the superior mesenteric artery and 3.46, 3.78 and 3.81 for the superior mesenteric vein, respectively. The image quality scores for the optimal monochromatic and the optimal monochromatic plus 40% iterative reconstruction groups were significantly greater than for the 70 KeV group (P < 0.05). The vascular CT value, image noise, background noise, CNR and SNR were significantly (P < 0.001) greater in the optimal monochromatic and the optimal monochromatic images plus 40% iterative reconstruction group than in the 70 KeV group. The optimal monochromatic plus 40% iterative reconstruction group had significantly (P < 0.05) lower image and background noise but higher CNR and SNR than the other two groups. Conclusion: The optimal monochromatic imaging combined with 40% iterative reconstruction using low-contrast agent dosage and low injection rate can significantly improve the image quality of the superior mesenteric artery and vein.

  1. A study on the angle between the abdominal aorta and the superior mesenteric artery by 3D image reconstruction

    International Nuclear Information System (INIS)

    Kim, Young Keun; Choi, Sung Kwan

    2003-01-01

    SMAS (Superior Mesenteric Artery Syndrome) is a disease caused by a chronic obstruction of the duodenum (transverse portion ), which is hardly detectable. However, it is known that when the superior mesenteric artery and abdominal aorta form a narrow angle, that the transverse portion of the duodenum is pressed down between the superior mesenteric artery and the abdominal aorta, and that this can lead to obstruction of the duodenum. Measuring this angle is a complicated job using conventional angiography, and results often turns out to be inaccurate. In addition, no attempt has been made to determine the value of this angle in Koreans. In this study, we conducted abdominal CT angiography using MIP (maximum intensity projection) on patients with no clinical evidence of SMAS in order to determine the angle at which the superior mesenteric artery branches from the abdominal aorta by using PC based software (Rapidia ver. 1.2) for the image reconstruction. Accordingly, we found that the mean angle between the abdominal aorta and the superior mesenteric artery was 50.05 ± 15.87 .deg. on average, and that the angle in men (53.64 ± 16.57 .deg.) is higher than in women (46.46 ± 14.98 .deg. ). We hope that the angles determined by our study will serve as an important indicator for detecting SMAS

  2. MR imaging characteristics of protoplasmic astrocytomas

    Energy Technology Data Exchange (ETDEWEB)

    Tay, Kevin L. [Royal Melbourne Hospital, Department of Radiology, Parkville, Victoria (Australia); Royal North Shore Hospital, Department of Radiology, St Leonards, New South Wales (Australia); Tsui, Alpha [Royal Melbourne Hospital, Department of Pathology, Parkville, Victoria (Australia); Phal, Pramit M.; Tress, Brian M. [Royal Melbourne Hospital, Department of Radiology, Parkville, Victoria (Australia); Drummond, Katharine J. [Royal Melbourne Hospital, Department of Neurosurgery, Parkville, Victoria (Australia)

    2011-06-15

    Protoplasmic astrocytomas are a poorly recognized and uncommon subtype of astrocytoma. While usually categorized with other low-grade gliomas, there is literature to suggest that protoplasmic astrocytomas have differences in biology compared to other gliomas in this group. This paper presents the MR imaging characteristics of a series of eight protoplasmic astrocytomas. We retrospectively reviewed MR images and histopathology of eight consecutive cases of histologically proven protoplasmic astrocytomas. Patients ranged from 17 to 51 years of age with a 5:3 male to female ratio. The tumors were located in the frontal or temporal lobes and tended to be large, well defined, and had a very high signal on T2 (close to cerebrospinal fluid). Generally, a large proportion of the tumor showed substantial signal suppression on T2 fluid-attenuated inversion recovery (FLAIR). Six of the eight lesions also demonstrated a partial or complete rim of reduced apparent diffusion coefficient (ADC) around the T2 FLAIR suppressing portion. The possibility that a primary cerebral neoplasm represents a protoplasmic astrocytoma should be considered in a patient with a large frontal or temporal tumor that has a very high signal on T2 with a large proportion of the tumor showing substantial T2 FLAIR suppression. A further clue is a partial or complete rim of reduced ADC. (orig.)

  3. Comparison of the signal-to-noise characteristics of quantum versus thermal ghost imaging

    International Nuclear Information System (INIS)

    O'Sullivan, Malcolm N.; Chan, Kam Wai Clifford; Boyd, Robert W.

    2010-01-01

    We present a theoretical comparison of the signal-to-noise characteristics of quantum versus thermal ghost imaging. We first calculate the signal-to-noise ratio of each process in terms of its controllable experimental conditions. We show that a key distinction is that a thermal ghost image always resides on top of a large background; the fluctuations in this background constitutes an intrinsic noise source for thermal ghost imaging. In contrast, there is a negligible intrinsic background to a quantum ghost image. However, for practical reasons involving achievable illumination levels, acquisition times for thermal ghost images are often much shorter than those for quantum ghost images. We provide quantitative predictions for the conditions under which each process provides superior performance. Our conclusion is that each process can provide useful functionality, although under complementary conditions.

  4. Superiority Of Graph-Based Visual Saliency GVS Over Other Image Segmentation Methods

    Directory of Open Access Journals (Sweden)

    Umu Lamboi

    2017-02-01

    Full Text Available Although inherently tedious the segmentation of images and the evaluation of segmented images are critical in computer vision processes. One of the main challenges in image segmentation evaluation arises from the basic conflict between generality and objectivity. For general segmentation purposes the lack of well-defined ground-truth and segmentation accuracy limits the evaluation of specific applications. Subjectivity is the most common method of evaluation of segmentation quality where segmented images are visually compared. This is daunting task however limits the scope of segmentation evaluation to a few predetermined sets of images. As an alternative supervised evaluation compares segmented images against manually-segmented or pre-processed benchmark images. Not only good evaluation methods allow for different comparisons but also for integration with target recognition systems for adaptive selection of appropriate segmentation granularity with improved recognition accuracy. Most of the current segmentation methods still lack satisfactory measures of effectiveness. Thus this study proposed a supervised framework which uses visual saliency detection to quantitatively evaluate image segmentation quality. The new benchmark evaluator uses Graph-based Visual Saliency GVS to compare boundary outputs for manually segmented images. Using the Berkeley Segmentation Database the proposed algorithm was tested against 4 other quantitative evaluation methods Probabilistic Rand Index PRI Variation of Information VOI Global Consistency Error GSE and Boundary Detection Error BDE. Based on the results the GVS approach outperformed any of the other 4 independent standard methods in terms of visual saliency detection of images.

  5. Radiometric and geometric characteristics of Pleiades images

    Science.gov (United States)

    Jacobsen, K.; Topan, H.; Cam, A.; Özendi, M.; Oruc, M.

    2014-11-01

    Pleiades images are distributed with 50 cm ground sampling distance (GSD) even if the physical resolution for nadir images is just 70 cm. By theory this should influence the effective GSD determined by means of point spread function at image edges. Nevertheless by edge enhancement the effective GSD can be improved, but this should cause enlarged image noise. Again image noise can be reduced by image restoration. Finally even optimized image restoration cannot improve the image information from 70 cm to 50 cm without loss of details, requiring a comparison of Pleiades image details with other very high resolution space images. The image noise has been determined by analysis of the whole images for any sub-area with 5 pixels times 5 pixels. Based on the standard deviation of grey values in the small sub-areas the image noise has been determined by frequency analysis. This leads to realistic results, checked by test targets. On the other hand the visual determination of image noise based on apparently homogenous sub-areas results in too high values because the human eye is not able to identify small grey value differences - it is limited to just approximately 40 grey value steps over the available gray value range, so small difference in grey values cannot be seen, enlarging results of a manual noise determination. A tri-stereo combination of Pleiades 1A in a mountainous, but partially urban, area has been analyzed and compared with images of the same area from WorldView-1, QuickBird and IKONOS. The image restoration of the Pleiades images is very good, so the effective image resolution resulted in a factor 1.0, meaning that the effective resolution corresponds to the nominal resolution of 50 cm. This does not correspond to the physical resolution of 70 cm, but by edge enhancement the steepness of the grey value profile across the edge can be enlarged, reducing the width of the point spread function. Without additional filtering edge enhancement enlarges the image

  6. Focal switching of photochromic fluorescent proteins enables multiphoton microscopy with superior image contrast.

    Science.gov (United States)

    Kao, Ya-Ting; Zhu, Xinxin; Xu, Fang; Min, Wei

    2012-08-01

    Probing biological structures and functions deep inside live organisms with light is highly desirable. Among the current optical imaging modalities, multiphoton fluorescence microscopy exhibits the best contrast for imaging scattering samples by employing a spatially confined nonlinear excitation. However, as the incident laser power drops exponentially with imaging depth into the sample due to the scattering loss, the out-of-focus background eventually overwhelms the in-focus signal, which defines a fundamental imaging-depth limit. Herein we significantly improve the image contrast for deep scattering samples by harnessing reversibly switchable fluorescent proteins (RSFPs) which can be cycled between bright and dark states upon light illumination. Two distinct techniques, multiphoton deactivation and imaging (MPDI) and multiphoton activation and imaging (MPAI), are demonstrated on tissue phantoms labeled with Dronpa protein. Such a focal switch approach can generate pseudo background-free images. Conceptually different from wave-based approaches that try to reduce light scattering in turbid samples, our work represents a molecule-based strategy that focused on imaging probes.

  7. Neural evidence for the use of digit-image mnemonic in a superior memorist: An fMRI study

    Directory of Open Access Journals (Sweden)

    Li-Jun eYin

    2015-03-01

    Full Text Available Some superior memorists demonstrated exceptional memory for reciting a large body of information. The underlying neural correlates, however, are seldom addressed. C.L., the current holder of Guinness World Record for reciting 67,890 digits in π, participated in this functional magnetic resonance imaging (fMRI study. Thirteen participants without any mnemonics training were included as controls. Our previous studies suggested that C.L. used a digit-image mnemonic in studying and recalling lists of digits, namely associating 2-digit groups of ‘00’ to ‘99’ with images and generating vivid stories out of them (Hu, Ericsson, Yang & Lu, 2009. Thus, 2-digit condition was included, with 1-digit numbers and letters as control conditions. We hypothesized that 2-digit condition in C.L. should elicit the strongest activity in the brain regions which are associated with his mnemonic. Functional MRI results revealed that bilateral frontal poles (FPs, BA10, left superior parietal lobule (SPL, left premotor cortex (PMC, and left dorsolateral prefrontal cortex (DLPFC, were more engaged in both the study and recall phase of 2-digit condition for C.L. relative to controls. Moreover, the left middle/inferior frontal gyri (M/IFG and intraparietal sulci (IPS were less engaged in the study phase of 2-digit condition for C.L. (vs. controls. These results suggested that C.L. relied more on brain regions that are associated with episodic memory other than verbal rehearsal while he used his mnemonic strategies. This study supported theoretical accounts of restructured cognitive mechanisms for the acquisition of superior memory performance.

  8. EFFECTS OF INDIVIDUAL CHARACTERISTICS AND ORGANIZATIONAL CONTEXT ON SUPERIORS' USE OF CONFLICT STYLES AND SUBORDINATES' SATISFACTION WITH SUPERVISION

    Directory of Open Access Journals (Sweden)

    Lee Kim Lian

    2008-01-01

    Full Text Available Data from 139 respondents from major industries showed that subordinates were more satisfied with their superiors' supervision through the exercise of integrating, compromising and obliging styles. On the contrary, subordinates who perceived their superiors as primarily using dominating and avoiding styles viewed them as incompetent in supervision and thus lowering their level of satisfaction with supervision. Among the conflict handling styles, integrating was most correlated with organic structure. The organic structure was found to be positively correlated with subordinates' satisfaction. These results implied that organic structure can be a potent force in maintaining organizational stability. The exercise of dominating style was found to be only marginally correlated with superior's age. Superior rank in lower hierarchy level was found to have a negative impact, albeit marginally on the exercise of dominating style. The present results also seemed to suggest that subordinates tend to be less satisfied with superiors with wider span of control.

  9. Diagnostic imagings and embolotherapy for the superior mesenteric vein-inferior vena cava shunt

    International Nuclear Information System (INIS)

    Morita, Yutaka; Yamada, Masataka; Miyata, Mutsuhiko; Kubo, Kohzo.

    1994-01-01

    Diagnostic imaging and embolization therapy for the uncommon portal and mesenteric vein-inferior vena cave shunt (PV·SMV-IVC shunt) are reported. As the frequency of clinical symptoms such as hematemesis, melena and confusion caused by gastrointestinal varices, or hepatoencephalopathy was about 40%, it was important for this disease entity to be diagnosed with noninvasive diagnostic images. The careful examination of the area around the right renal vein was able to overcome the low diagnostic rate of 20-40% obtained with US and CT images. In cases of simple PV·SMV-IVC shut without gastrointestinal varices, embolization therapy using steel coils and done by the intravenous approach is easy and noninvasive. On the other hand, in cases of complex PV-SMV-IVC shunt with gastrointestinal varices, dual balloon occluded embolization therapy using a liquid sclerosing agent and done by the intravenous and portal approaches is preferable. (author)

  10. Dual-energy CT and ceramic or titanium prostheses material reduce CT artifacts and provide superior image quality of total knee arthroplasty.

    Science.gov (United States)

    Kasparek, Maximilian F; Töpker, Michael; Lazar, Mathias; Weber, Michael; Kasparek, Michael; Mang, Thomas; Apfaltrer, Paul; Kubista, Bernd; Windhager, Reinhard; Ringl, Helmut

    2018-06-07

    To evaluate the influence of different scan parameters for single-energy CT and dual-energy CT, as well as the impact of different material used in a TKA prosthesis on image quality and the extent of metal artifacts. Eight pairs of TKA prostheses from different vendors were examined in a phantom set-up. Each pair consisted of a conventional CoCr prosthesis and the corresponding anti-allergic prosthesis (full titanium, ceramic, or ceramic-coated) from the same vendor. Nine different (seven dual-energy CT and two single-energy CT) scan protocols with different characteristics were used to determine the most suitable CT protocol for TKA imaging. Quantitative image analysis included assessment of blooming artifacts (metal implants appear thicker on CT than they are, given as virtual growth in mm in this paper) and streak artifacts (thick dark lines around metal). Qualitative image analysis was used to investigate the bone-prosthesis interface. The full titanium prosthesis and full ceramic knee showed significantly fewer blooming artifacts compared to the standard CoCr prosthesis (mean virtual growth 0.6-2.2 mm compared to 2.9-4.6 mm, p energy CT protocols showed less blooming (range 3.3-3.8 mm) compared to single-energy protocols (4.6-5.5 mm). The full titanium and full ceramic prostheses showed significantly fewer streak artifacts (mean standard deviation 77-86 Hounsfield unit (HU)) compared to the standard CoCr prosthesis (277-334 HU, p energy CT protocols had fewer metal streak artifacts (215-296 HU compared to single-energy CT protocols (392-497 HU)). Full titanium and ceramic prostheses were ranked superior with regard to the image quality at the bone/prosthesis interface compared to a standard CoCr prosthesis, and all dual-energy CT protocols were ranked better than single-energy protocols. Dual-energy CT and ceramic or titanium prostheses reduce CT artifacts and provide superior image quality of total knee arthroplasty at the bone/prosthesis interface

  11. Steganalysis based on reducing the differences of image statistical characteristics

    Science.gov (United States)

    Wang, Ran; Niu, Shaozhang; Ping, Xijian; Zhang, Tao

    2018-04-01

    Compared with the process of embedding, the image contents make a more significant impact on the differences of image statistical characteristics. This makes the image steganalysis to be a classification problem with bigger withinclass scatter distances and smaller between-class scatter distances. As a result, the steganalysis features will be inseparate caused by the differences of image statistical characteristics. In this paper, a new steganalysis framework which can reduce the differences of image statistical characteristics caused by various content and processing methods is proposed. The given images are segmented to several sub-images according to the texture complexity. Steganalysis features are separately extracted from each subset with the same or close texture complexity to build a classifier. The final steganalysis result is figured out through a weighted fusing process. The theoretical analysis and experimental results can demonstrate the validity of the framework.

  12. Thermal imaging cameras characteristics and performance

    CERN Document Server

    Williams, Thomas

    2009-01-01

    The ability to see through smoke and mist and the ability to use the variances in temperature to differentiate between targets and their backgrounds are invaluable in military applications and have become major motivators for the further development of thermal imagers. As the potential of thermal imaging is more clearly understood and the cost decreases, the number of industrial and civil applications being exploited is growing quickly. In order to evaluate the suitability of particular thermal imaging cameras for particular applications, it is important to have the means to specify and measur

  13. Imaging characteristics in rotational panoramic radiography

    International Nuclear Information System (INIS)

    Sanderink, G.C.H.

    1987-01-01

    This study is concerned with imaging quality in rotational panoramic radiography. This imaging technique records an image of a curved layer within the object radiographed. The shape of this layer normally corresponds with the average form of the dental arch. In the centre of the layer a plane can be found which is depicted with a minimum of unsharpness. Unsharpness increases and the horizontal magnification changes as distance increases from that central plane. The image quality of the layer has been analyzed with the use of mathematical models to estimate the performance of the radiographic diagnostic system. Despite the application of these increasingly sophisticated models the question remains: will the results of the calculations based on these models adequately predict the diagnostic effectiveness of this type of imaging system? In this study a comparison is made between the theoretically determined quality of the system and the diagnostic quality using the observer as a measuring instrument. Experiments were carried out to measure the total unsharpness occurring in rotational panoramic radiography. 116 refs.; 114 figs.; 54 tabs

  14. ASSESSMENT OF LANDSCAPE CHARACTERISTICS ON THEMATIC IMAGE CLASSIFICATION ACCURACY

    Science.gov (United States)

    Landscape characteristics such as small patch size and land cover heterogeneity have been hypothesized to increase the likelihood of misclassifying pixels during thematic image classification. However, there has been a lack of empirical evidence, to support these hypotheses. This...

  15. Imaging characteristics of different mammographic screens.

    Science.gov (United States)

    Kuhn, H; Knüpfer, W

    1992-01-01

    A study of mammography systems with green-emitting screens was conducted to determine how the image quality parameters (apart from dose requirement), such as modulation transfer function (MTF) and Wiener spectrum (WS), depend on the dye content of the compound and coating weight of the screen. In addition, the contribution to total noise of the individual components, i.e., film, screen, and quantum noise, was studied. The quantities derived from MTF and WS, namely detective quantum efficiency (DQE) and noise equivalent quanta (NEQ), were also investigated in regard to their dose dependency. It can be demonstrated that the MTF of the screens becomes more favorable when the dye content is increased, while noise is not significantly affected. This suggests the use of a mammography screen capable of greater detail recognition, requiring at least double the dose of today's conventional systems with approximately 80 microGy system dose. On the other hand, the manufacture of a screen with about 60% of the dose of the conventional system is possible with very little loss in image quality. For the systems in common use today (80 microGy), quantum noise represents a considerable share of the total noise at low spatial frequencies, whereas in high spatial frequencies, the graininess of the film dominates quantum noise and screen structure.

  16. Randomized trial for superiority of high field strength intra-operative magnetic resonance imaging guided resection in pituitary surgery.

    Science.gov (United States)

    Tandon, Vivek; Raheja, Amol; Suri, Ashish; Chandra, P Sarat; Kale, Shashank S; Kumar, Rajinder; Garg, Ajay; Kalaivani, Mani; Pandey, Ravindra M; Sharma, Bhawani S

    2017-03-01

    Till date there are no randomized trials to suggest the superiority of intra-operative magnetic resonance imaging (IOMRI) guided trans-sphenoidal pituitary resection over two dimensional fluoroscopic (2D-F) guided resections. We conducted this trial to establish the superiority of IOMRI in pituitary surgery. Primary objective was to compare extent of tumor resection between the two study arms. It was a prospective, randomized, outcome assessor and statistician blinded, two arm (A: IOMRI, n=25 and B: 2D-F, n=25), parallel group clinical trial. 4 patients from IOMRI group cross-over to 2D-F group and were consequently analyzed in latter group, based on modified intent to treat method. A total of 50 patients were enrolled till completion of trial (n=25 in each study arm). Demographic profile and baseline parameters were comparable among the two arms (p>0.05) except for higher number of endoscopic procedures and experienced neurosurgeons (>10years) in arm B (p=0.02, 0.002 respectively). Extent of resection was similar in both study arms (A, 94.9% vs B, 93.6%; p=0.78), despite adjusting for experience of operating surgeon and use of microscope/endoscope for surgical resection. We observed that use of IOMRI helped optimize the extent of resection in 5/20 patients (25%) for pituitary tumor resection in-group A. Present study failed to observe superiorty of IOMRI over conventional 2D-F guided resection in pituitary macroadenoma surgery. By use of this technology, younger surgeons could validate their results intra-operatively and hence could increase EOR without causing any increase in complications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Personality characteristics and body image in obese individuals.

    Science.gov (United States)

    Sarısoy, Gökhan; Atmaca, Ayşegül; Ecemiş, Gülçin; Gümüş, Kübra; Pazvantoğlu, Ozan

    2014-06-01

    The aim of this study was to determine the personality characteristics of obese and morbidly obese individuals with no psychiatric disorder and the correlation between these characteristics and body image and self-esteem. Sixty-nine obese individuals and 69 healthy controls, matched in age, sex and marital status, were included in the study. Psychiatric disorders were excluded for all participants using SCID-I and II. Obese and healthy volunteers were compared in terms of body image, self-esteem and personality characteristics. TCI harm avoidance scores were higher in obese individuals compared to healthy controls. Harm avoidance scores were also higher in individuals with morbid obesity compared to non-morbid individuals, while self-directedness and persistence scores were lower. Body image dissatisfaction was higher in obese individuals. There was a negative correlation in obese individuals between body image and self-esteem scale scores and harm avoidance scores, and a positive correlation with self-directedness scores. An elevated harm avoidance temperament characteristic may be correlated with obesity. Furthermore, high harm avoidance, low self-directedness and low persistence may be significant personality characteristics in a process leading to morbid obesity. In addition, harm avoidance temperament and self-directedness personality characteristics may be correlated with body image dissatisfaction and self-esteem in obese individuals. Copyright © 2012 Wiley Publishing Asia Pty Ltd.

  18. Fast image matching algorithm based on projection characteristics

    Science.gov (United States)

    Zhou, Lijuan; Yue, Xiaobo; Zhou, Lijun

    2011-06-01

    Based on analyzing the traditional template matching algorithm, this paper identified the key factors restricting the speed of matching and put forward a brand new fast matching algorithm based on projection. Projecting the grayscale image, this algorithm converts the two-dimensional information of the image into one-dimensional one, and then matches and identifies through one-dimensional correlation, meanwhile, because of normalization has been done, when the image brightness or signal amplitude increasing in proportion, it could also perform correct matching. Experimental results show that the projection characteristics based image registration method proposed in this article could greatly improve the matching speed, which ensuring the matching accuracy as well.

  19. Chemical Exchange Saturation Transfer MR Imaging Is Superior to Diffusion Tensor Imaging in the Diagnosis and Severity Evaluation of Parkinson's Disease: a Study on Substantia Nigra and Striatum

    Directory of Open Access Journals (Sweden)

    Chunmei eLi

    2015-10-01

    Full Text Available Parkinson’s disease (PD is a neurodegenerative disorder characterized by nigrostriatal cell loss. To date the diagnosis of PD is still based primarily on the clinical manifestations which may be typical and obvious only in advanced-stage PD. Thus, it is crucial to find a reliable marker for the diagnosis of PD. We conducted this study to assess the diagnostic efficiency of chemical-exchange-saturation-transfer (CEST imaging and diffusion-tensor imaging (DTI in PD at 3 Tesla by evaluating changes on substantia nigra and striatum. Twenty-three PD patients and twenty-three age-matched normal controls were recruited. All patients and controls were imaged on a 3 Tesla MR system, using an 8-channel head coil. CEST imaging was acquired in two transverse slices of the head, including substantia nigra and striatum. The magnetization-transfer-ratio asymmetry at 3.5 ppm, MTRasym(3.5ppm, and the total CEST signal intensity between 0 and 4 ppm were calculated. Multi-slice DTI was acquired for all the patients and normal controls. Quantitative analysis was performed on the substantia nigra, globus pallidus, putamen and caudate. The MTRasym(3.5ppm value, the total CEST signal intensity and fractional anisotropy (FA value of the substantia nigra were all significantly lower in PD patients than in normal controls (P = 0.003, P = 0.004 and P < 0.001, respectively. The MTRasym(3.5ppm values of the putamen and the caudate were significantly higher in PD patients than in normal controls (P = 0.010 and P = 0.009, respectively. There were no significant differences for the mean diffusivity (MD in these four regions between PD patients and normal controls. In conclusion, CEST MR imaging provided multiple CEST image contrasts in the substantia nigra and the striatum in PD and may be superior to DTI in the diagnosis of PD.

  20. Abnormal left superior temporal gyrus volumes in children and adolescents with bipolar disorder: a magnetic resonance imaging study.

    Science.gov (United States)

    Chen, Hua Hsua; Nicoletti, Mark A; Hatch, John P; Sassi, Roberto B; Axelson, David; Brambilla, Paolo; Monkul, E Serap; Keshavan, Matcheri S; Ryan, Neal D; Birmaher, Boris; Soares, Jair C

    2004-06-03

    Abnormalities in left superior temporal gyrus (STG) have been reported in adult bipolar patients. However, it is not known whether such abnormalities are already present early in the course of this illness. Magnetic resonance imaging (MRI) morphometric analysis of STG was performed in 16 DSM-IV children and adolescents with bipolar disorder (mean age+/-SD 15.5+/-3.4 years) and 21 healthy controls (mean age+/-SD 16.9+/-3.8 years). Subjects underwent a 3D spoiled gradient recalled acquisition MRI examination. Using analysis of covariance with age, gender and intra-cranial brain volume as covariates, we found significantly smaller left total STG volumes in bipolar patients (12.5+/-1.5 cm(3)) compared with healthy controls (13.6+/-2.5 cm(3)) (F=4.45, d.f.=1, 32, P=0.04). This difference was accounted for by significantly smaller left and right STG white matter volumes in bipolar patients. Decreased white matter connections may be the core of abnormalities in STG, which is an important region for speech, language and communication, and could possibly underlie neurocognitive deficits present in bipolar patients.

  1. The superiority and benefits of whole body imaging after radioiodine -131 therapy over radioiodine 131 diagnostic imaging in management of thyroid carcinomas.

    Energy Technology Data Exchange (ETDEWEB)

    Aleid, M A [Al-Mostansyria university, college of medicine P.O.Box 14132, Baghdad, (Iraq)

    1995-10-01

    A comparison between diagnostic and post therapeutic radioiodine imaging methods utilized in detection of thyroid metastases in 34 patients with well differentiated thyroid cancer was performed. The study revealed that the differences in detection on neck activity only between the two methods for papillary and follicular thyroid cancer were 35% and 27% respectively. While the overall detection percentages in both papillary and follicular thyroid cancers cases were 23% in diagnostic and 76% in post therapy scintigrams and the detection difference between the methods was 53% when all lesions throughout the body were seen on scintigram for only follicular thyroid cancer cases were counted, the detection percentage was increased up to 109%. It is clear that post therapeutic scans visualize an additional site activity not shown in diagnostic scans. There fore, post therapeutic imaging method is far superior to diagnostic imaging method and highly sensitive in visualization of thyroid metastases. On the other hand, this research also achieves many scientific and financial benefits. Therefore. This method should be adopted in management and follow up of well differentiated malignancies. 2 figs., 2 tabs.

  2. The superiority and benefits of whole body imaging after radioiodine -131 therapy over radioiodine 131 diagnostic imaging in management of thyroid carcinomas

    International Nuclear Information System (INIS)

    Aleid, M.A.

    1995-01-01

    A comparison between diagnostic and post therapeutic radioiodine imaging methods utilized in detection of thyroid metastases in 34 patients with well differentiated thyroid cancer was performed. The study revealed that the differences in detection on neck activity only between the two methods for papillary and follicular thyroid cancer were 35% and 27% respectively. While the overall detection percentages in both papillary and follicular thyroid cancers cases were 23% in diagnostic and 76% in post therapy scintigrams and the detection difference between the methods was 53% when all lesions throughout the body were seen on scintigram for only follicular thyroid cancer cases were counted, the detection percentage was increased up to 109%. It is clear that post therapeutic scans visualize an additional site activity not shown in diagnostic scans. There fore, post therapeutic imaging method is far superior to diagnostic imaging method and highly sensitive in visualization of thyroid metastases. On the other hand, this research also achieves many scientific and financial benefits. Therefore. This method should be adopted in management and follow up of well differentiated malignancies. 2 figs., 2 tabs

  3. Noise characteristics of neutron images obtained by cooled CCD device

    International Nuclear Information System (INIS)

    Taniguchi, Ryoichi; Sasaki, Ryoya; Okuda, Shuichi; Okamoto, Ken-Ichi; Ogawa, Yoshihiro; Tsujimoto, Tadashi

    2009-01-01

    The noise characteristics of a cooled CCD device induced by neutron and gamma ray irradiation have been investigated. In the cooled CCD images, characteristic white spot noises (CCD noise) frequently appeared, which have a shape like a pixel in most cases and their brightness is extremely high compared with that of the image pattern. They could be divided into the two groups, fixed pattern noise (FPN) and random noise. The former always appeared in the same position in the image and the latter appeared at any position. In the background image, nearly all of the CCD noises were found to be the FPN, while many of them were the random noise during the irradiation. The random CCD noises increased with irradiation and decreased soon after the irradiation. In the case of large irradiation, a part of the CCD noise remained as the FPN. These facts suggest that the CCD noise is a phenomenon strongly relating to radiation damage of the CCD device.

  4. Effect of magnetic resonance imaging characteristics on uterine fibroid treatment

    Directory of Open Access Journals (Sweden)

    Duc NM

    2018-04-01

    Full Text Available Nguyen Minh Duc, Huynh Quang HuyDepartment of Radiology, Pham Ngoc Thach University of Medicine, Ho Chi Minh City, VietnamAbstract: Uterine fibroids are the most common gynecological benign tumors adversely affecting the quality of life of women of a reproductive age. Magnetic resonance imaging (MRI is efficient at localizing the site of lesions and characterizing uterine fibroids before treatment. Understanding the different characteristics of uterine fibroids on MRI is essential, because it not only enables prompt diagnosis, but also guides the development of suitable therapeutic methods. This pictorial review demonstrates the effect of MRI features on uterine fibroid treatment. Keywords: uterine fibroids, characteristics, magnetic resonance imaging, treatments

  5. Pilomatricomas in children: imaging characteristics with pathologic correlation

    International Nuclear Information System (INIS)

    Lim, Hyun Wook; Im, Soo Ah; Lim, Gye-Yeon; Park, Hyun Jin; Lee, Heejeong; Sung, Mi Sook; Kang, Bong Joo; Kim, Jee Young

    2007-01-01

    Although pilomatricoma commonly occurs in children, there is still a poor understanding of the imaging characteristics of pilomatricoma and lack of agreement regarding its imaging findings and histopathologic features. To characterize the radiologic appearance of pilomatricomas on US, CT, and MR and to correlate the imaging findings with histopathologic features. The imaging findings of 47 pilomatricomas on US (n = 17), CT (n = 31), and MR (n = 5) were retrospectively evaluated. Pathologic specimens of all cases were reviewed and compared with imaging findings. All lesions were well-circumscribed, subcutaneous nodules with partial attachment to the overlying skin. On US, the lesions were mostly hyperechoic with posterior acoustic shadowing and hypoechoic rim. On CT, they appeared as enhancing soft-tissue masses with varying amounts of calcification. MR findings were internal reticulations and patchy areas on T2-weighted images and contrast-enhanced T1-weighted images, corresponding to edematous stroma on pathology. Peritumoral inflammatory changes and connective capsule on pathology were well correlated with imaging findings. Pilomatricoma should be considered when US or CT shows a well-defined hyperechoic or calcific nodule in subcutaneous fat attached to the skin in children. MR images may be helpful in diagnosis. Pathologic findings are well correlated with imaging findings. (orig.)

  6. Ultrasound introscopic image quantitative characteristics for medical diagnosis

    Science.gov (United States)

    Novoselets, Mikhail K.; Sarkisov, Sergey S.; Gridko, Alexander N.; Tcheban, Anatoliy K.

    1993-09-01

    The results on computer aided extraction of quantitative characteristics (QC) of ultrasound introscopic images for medical diagnosis are presented. Thyroid gland (TG) images of Chernobil Accident sufferers are considered. It is shown that TG diseases can be associated with some values of selected QCs of random echo distribution in the image. The possibility of these QCs usage for TG diseases recognition in accordance with calculated values is analyzed. The role of speckle noise elimination in the solution of the problem on TG diagnosis is considered too.

  7. Flow velocity and volume measurement of superior and inferior mesenteric artery with cine phase contrast magnetic resonance imaging

    International Nuclear Information System (INIS)

    Naganawa, Shinji; Cooper, T.G.; Jenner, G.; Potchen, E.J.; Ishigaki, Takeo.

    1994-01-01

    The flow velocity and volume of the superior and inferior mesenteric arteries (SMA, IMA) were measured with cine phase contrast magnetic resonance (MR) imaging in five healthy volunteers. Each volunteer was first measured in a fasting state, and then one, two, and three hours after a meal. The average SMA flow volume of the volunteers was 230.3±46.8 ml/min (mean±standard error) during the fasting state, and 714.7±207.7 ml/min, 339.2±85.7 ml/min, and 263.8±21.0 ml/min, respectively, at one, two, and three hours postmeal. The increase at one hour postmeal was statistically significant (p<0.05). The corresponding flow measurements in the IMA were 63.1±11.2 ml/min, 67.6±11.2 ml/min, 57.9±8.6 ml/min, and 53.2±6.8 ml/min. These values do not represent a statistically significant flow volume change in the IMA. In all volunteers, the SMA volumetric flow increased the most one hour after the food challenge (72-400% relative to baseline). Diastolic velocity in the SMA increased significantly one hour postmeal, but systolic velocity did not change significantly. The IMA did not demonstrate a significant change in either systolic or diastolic velocity. The difference between the SMA and IMA in the way of reacting against the food challenge is thought to represent the difference between the requirements of small and large intestine for blood supply after the food challenge. These data demonstrate the possibility of this modality for the assessment of conditions such as chronic mesenteric ischemia. (author)

  8. Performance characteristics of proximity focused ultraviolet image converters

    Science.gov (United States)

    Williams, J. T.; Feibelman, W. A.

    1973-01-01

    Performance characteristics of Bendix type BX 8025-4522 proximity focused image tubes for UV to visible light conversion are presented. Quantum efficiency, resolution, background, geometric distortion, and environmental test results are discussed. The converters use magnesium fluoride input windows with Cs-Te photocathodes and P-11 phosphors on fiber optic output windows.

  9. Imaging with 124I in differentiated thyroid carcinoma: is PET/MRI superior to PET/CT?

    International Nuclear Information System (INIS)

    Binse, I.; Poeppel, T.D.; Ruhlmann, M.; Gomez, B.; Bockisch, A.; Rosenbaum-Krumme, S.J.; Umutlu, L.

    2016-01-01

    The aim of this study was to compare integrated PET/CT and PET/MRI for their usefulness in detecting and categorizing cervical iodine-positive lesions in patients with differentiated thyroid cancer using 124 I as tracer. The study group comprised 65 patients at high risk of iodine-positive metastasis who underwent PET/CT (low-dose CT scan, PET acquisition time 2 min; PET/CT 2 ) followed by PET/MRI of the neck 24 h after 124 I administration. PET images from both modalities were analysed for the numbers of tracer-positive lesions. Two different acquisition times were used for the comparisons, one matching the PET/CT 2 acquisition time (2 min, PET/MRI 2 ) and the other covering the whole MRI scan time (30 min, PET/MRI 30 ). Iodine-positive lesions were categorized as metastasis, thyroid remnant or inconclusive according to their location on the PET/CT images. Morphological information provided by MRI was considered for evaluation of lesions on PET/MRI and for volume information. PET/MRI 2 detected significantly more iodine-positive metastases and thyroid remnants than PET/CT 2 (72 vs. 60, p = 0.002, and 100 vs. 80, p = 0.001, respectively), but the numbers of patients with at least one tumour lesion identified were not significantly different (21/65 vs. 17/65 patients). PET/MRI 30 tended to detect more PET-positive metastases than PET/MRI 2 (88 vs. 72), but the difference was not significant (p = 0.07). Of 21 lesions classified as inconclusive on PET/CT, 5 were assigned to metastasis or thyroid remnant when evaluated by PET/MRI. Volume information was available in 34 % of iodine-positive metastases and 2 % of thyroid remnants on PET/MRI. PET/MRI of the neck was found to be superior to PET/CT in detecting iodine-positive lesions. This was attributed to the higher sensitivity of the PET component, Although helpful in some cases, we found no substantial advantage of PET/MRI over PET/CT in categorizing iodine-positive lesions as either metastasis or thyroid remnant

  10. Imaging with {sup 124}I in differentiated thyroid carcinoma: is PET/MRI superior to PET/CT?

    Energy Technology Data Exchange (ETDEWEB)

    Binse, I.; Poeppel, T.D.; Ruhlmann, M.; Gomez, B.; Bockisch, A.; Rosenbaum-Krumme, S.J. [University of Duisburg-Essen, Medical Faculty, Department of Nuclear Medicine, Essen (Germany); Umutlu, L. [University of Duisburg-Essen, Medical Faculty, Department of Radiology, Essen (Germany)

    2016-06-15

    The aim of this study was to compare integrated PET/CT and PET/MRI for their usefulness in detecting and categorizing cervical iodine-positive lesions in patients with differentiated thyroid cancer using {sup 124}I as tracer. The study group comprised 65 patients at high risk of iodine-positive metastasis who underwent PET/CT (low-dose CT scan, PET acquisition time 2 min; PET/CT{sub 2}) followed by PET/MRI of the neck 24 h after {sup 124}I administration. PET images from both modalities were analysed for the numbers of tracer-positive lesions. Two different acquisition times were used for the comparisons, one matching the PET/CT{sub 2} acquisition time (2 min, PET/MRI{sub 2}) and the other covering the whole MRI scan time (30 min, PET/MRI{sub 30}). Iodine-positive lesions were categorized as metastasis, thyroid remnant or inconclusive according to their location on the PET/CT images. Morphological information provided by MRI was considered for evaluation of lesions on PET/MRI and for volume information. PET/MRI{sub 2} detected significantly more iodine-positive metastases and thyroid remnants than PET/CT{sub 2} (72 vs. 60, p = 0.002, and 100 vs. 80, p = 0.001, respectively), but the numbers of patients with at least one tumour lesion identified were not significantly different (21/65 vs. 17/65 patients). PET/MRI{sub 30} tended to detect more PET-positive metastases than PET/MRI{sub 2} (88 vs. 72), but the difference was not significant (p = 0.07). Of 21 lesions classified as inconclusive on PET/CT, 5 were assigned to metastasis or thyroid remnant when evaluated by PET/MRI. Volume information was available in 34 % of iodine-positive metastases and 2 % of thyroid remnants on PET/MRI. PET/MRI of the neck was found to be superior to PET/CT in detecting iodine-positive lesions. This was attributed to the higher sensitivity of the PET component, Although helpful in some cases, we found no substantial advantage of PET/MRI over PET/CT in categorizing iodine

  11. Characteristics of Tau and Its Ligands in PET Imaging

    Directory of Open Access Journals (Sweden)

    Ryuichi Harada

    2016-01-01

    Full Text Available Tau deposition is one of the neuropathological hallmarks in Alzheimer’s disease as well as in other neurodegenerative disorders called tauopathies. Recent efforts to develop selective tau radiopharmaceuticals have allowed the visualization of tau deposits in vivo. In vivo tau imaging allows the assessment of the regional distribution of tau deposits in a single human subject over time for determining the pathophysiology of tau accumulation in aging and neurodegenerative conditions as well as for application in drug discovery of anti-dementia drugs as surrogate markers. However, tau deposits show complicated characteristics because of different isoform composition, histopathology, and ultrastructure in various neurodegenerative conditions. In addition, since tau radiopharmaceuticals possess different chemotype classes, they may show different binding characteristics with heterogeneous tau deposits. In this review, we describe the characteristics of tau deposits and their ligands that have β-sheet binding properties, and the status of tau imaging in clinical studies.

  12. Solid-state, flat-panel, digital radiography detectors and their physical imaging characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Cowen, A.R. [LXi Research, Academic Unit of Medical Physics, University of Leeds, West Yorkshire (United Kingdom)], E-mail: a.r.cowen@leeds.ac.uk; Kengyelics, S.M.; Davies, A.G. [LXi Research, Academic Unit of Medical Physics, University of Leeds, West Yorkshire (United Kingdom)

    2008-05-15

    Solid-state, digital radiography (DR) detectors, designed specifically for standard projection radiography, emerged just before the turn of the millennium. This new generation of digital image detector comprises a thin layer of x-ray absorptive material combined with an electronic active matrix array fabricated in a thin film of hydrogenated amorphous silicon (a-Si:H). DR detectors can offer both efficient (low-dose) x-ray image acquisition plus on-line readout of the latent image as electronic data. To date, solid-state, flat-panel, DR detectors have come in two principal designs, the indirect-conversion (x-ray scintillator-based) and the direct-conversion (x-ray photoconductor-based) types. This review describes the underlying principles and enabling technologies exploited by these designs of detector, and evaluates their physical imaging characteristics, comparing performance both against each other and computed radiography (CR). In standard projection radiography indirect conversion DR detectors currently offer superior physical image quality and dose efficiency compared with direct conversion DR and modern point-scan CR. These conclusions have been confirmed in the findings of clinical evaluations of DR detectors. Future trends in solid-state DR detector technologies are also briefly considered. Salient innovations include WiFi-enabled, portable DR detectors, improvements in x-ray absorber layers and developments in alternative electronic media to a-Si:H.

  13. Some distinguishing characteristics of contour and texture phenomena in images

    Science.gov (United States)

    Jobson, Daniel J.

    1992-01-01

    The development of generalized contour/texture discrimination techniques is a central element necessary for machine vision recognition and interpretation of arbitrary images. Here, the visual perception of texture, selected studies of texture analysis in machine vision, and diverse small samples of contour and texture are all used to provide insights into the fundamental characteristics of contour and texture. From these, an experimental discrimination scheme is developed and tested on a battery of natural images. The visual perception of texture defined fine texture as a subclass which is interpreted as shading and is distinct from coarse figural similarity textures. Also, perception defined the smallest scale for contour/texture discrimination as eight to nine visual acuity units. Three contour/texture discrimination parameters were found to be moderately successful for this scale discrimination: (1) lightness change in a blurred version of the image, (2) change in lightness change in the original image, and (3) percent change in edge counts relative to local maximum.

  14. Kinematic magnetic resonance imaging (MRI) of the normal shoulder: assessment of the shapes and signals of the superior and inferior labra with abductive movement using an open-type imager.

    OpenAIRE

    Togami, Izumi; Sasai, Nobuya; Tsunoda, Masatoshi; Sei, Tetsuro; Yabuki, Takayuki; Kitagawa, Takahiro; Mitani, Masahiko; Akaki, Shiro; Kuroda, Masahiro; Hiraki, Yoshio

    2001-01-01

    A preliminary study was conducted to evaluate the superior and inferior glenoid labra with abductive movement using an open-type MR unit in asymptomatic healthy volunteers. Both fast low angle shot (FLASH) and turbo spin echo (TSE) images were obtained to evaluate the shapes of both the superior and inferior labra, as well as to assess changes in signal at these sites. As the abduction angle was increased, the shape of the superior labrum changed from round or triangular to crescentic and a h...

  15. Image degradation characteristics and restoration based on regularization for diffractive imaging

    Science.gov (United States)

    Zhi, Xiyang; Jiang, Shikai; Zhang, Wei; Wang, Dawei; Li, Yun

    2017-11-01

    The diffractive membrane optical imaging system is an important development trend of ultra large aperture and lightweight space camera. However, related investigations on physics-based diffractive imaging degradation characteristics and corresponding image restoration methods are less studied. In this paper, the model of image quality degradation for the diffraction imaging system is first deduced mathematically based on diffraction theory and then the degradation characteristics are analyzed. On this basis, a novel regularization model of image restoration that contains multiple prior constraints is established. After that, the solving approach of the equation with the multi-norm coexistence and multi-regularization parameters (prior's parameters) is presented. Subsequently, the space-variant PSF image restoration method for large aperture diffractive imaging system is proposed combined with block idea of isoplanatic region. Experimentally, the proposed algorithm demonstrates its capacity to achieve multi-objective improvement including MTF enhancing, dispersion correcting, noise and artifact suppressing as well as image's detail preserving, and produce satisfactory visual quality. This can provide scientific basis for applications and possesses potential application prospects on future space applications of diffractive membrane imaging technology.

  16. Characterization of clinical-imaging characteristics of the binswanger's disease

    International Nuclear Information System (INIS)

    Rodriguez Mutuberria, Livan; Serra Valdes, Yusimi

    2002-01-01

    A review was made to go deep into the understanding of vascular dementias that behave as the second cause of dementia in practice. Binswanger's disease is one of the most important among them. Its detection has progressively increased with the continual improvement of the radiological diagnostic tools that allow to identify the ischemic damage of the hemispherical cerebral white matter and the presence of lacunar infarctions. It is a disease of chronic course and inexorably progressive that is characterized by the association of subcortical cognitive dysfunction, evidence of cerebrovascular disease, Parkinsonian rigidity and vesicle dysfunction with a characteristic imaging picture. The clinical picture and the main imaging characteristics are explained in this paper and the pathogens of the disease is briefly described

  17. Nuclear magnetic resonance imaging characteristics of gallstones in vitro

    International Nuclear Information System (INIS)

    Moon, K.L. Jr.; Hricak, H.; Margulis, A.R.; Bernhoft, R.; Way, L.W.; Filly, R.A.; Crooks, L.E.

    1983-01-01

    The nuclear magnetic resonance (NMR) imaging characteristics of gallstones of various composition from 36 patients were studied in vitro using a spin-echo imaging technique. The majority of gallstones (83%) produced no measurable NMR signal despite having a mean water content of 12% and a mean cholesterol content of 61%. Six (17%) of the stones had a weak but measurable signal in the center of the stone, which was thought to represent signal from water in clefts or pores within the stones. The mean water and cholesterol content of the stones with measurable signal did not differ significantly from that of stones with no signal. A possible explanation for these findings, based on the known NMR characteristics of solid materials, is offered

  18. Advances in computed radiography systems and their physical imaging characteristics

    International Nuclear Information System (INIS)

    Cowen, A.R.; Davies, A.G.; Kengyelics, S.M.

    2007-01-01

    Radiological imaging is progressing towards an all-digital future, across the spectrum of medical imaging techniques. Computed radiography (CR) has provided a ready pathway from screen film to digital radiography and a convenient entry point to PACS. This review briefly revisits the principles of modern CR systems and their physical imaging characteristics. Wide dynamic range and digital image enhancement are well-established benefits of CR, which lend themselves to improved image presentation and reduced rates of repeat exposures. However, in its original form CR offered limited scope for reducing the radiation dose per radiographic exposure, compared with screen film. Recent innovations in CR, including the use of dual-sided image readout and channelled storage phosphor have eased these concerns. For example, introduction of these technologies has improved detective quantum efficiency (DQE) by approximately 50 and 100%, respectively, compared with standard CR. As a result CR currently affords greater scope for reducing patient dose, and provides a more substantive challenge to the new solid-state, flat-panel, digital radiography detectors

  19. [Diagnostic imaging of high-grade astrocytoma: heterogeneity of clinical manifestation, image characteristics, and histopathological findings].

    Science.gov (United States)

    Okajima, Kaoru; Ohta, Yoshio

    2012-10-01

    Recent developments in diagnostic radiology, which have enabled accurate differential diagnoses of brain tumors, have been well described in the last three decades. MR and PET imaging can also provide information to predict histological grades and prognoses that might influence treatment strategies. However, high-grade astrocytomas consist of many different subtypes that are associated with different imaging and histological characteristics. Hemorrhage and necrosis results in a variety of imaging features, and infiltrative tumor growth entrapping normal neurons may cause different clinical manifestations. We reviewed patients with high-grade astrocytomas that showed various imaging characteristics, with special emphasis on initial symptoms and histological features. Clinicopathological characteristics of astrocytomas were also compared with other malignant tumors. Neurological deficits were not notable in patients with grade 3-4 astrocytomas when they showed infiltrative tumor growth, while brain metastases with compact cellular proliferation caused more neurological symptoms. Infiltrative tumors did not show any enhancing masses on MR imaging, but these tumors may show intratumor heterogeneity. Seizures were reported to be more frequent in low-grade glioma and in secondary glioblastoma. Tumor heterogeneity was also reported in molecular genetic profile, and investigators identified some subsets of astrocytomas. They investigated IHD1/2 mutation, EGFR amplification, TP53 mutation, Ki-67 index, etc. In summary, high-grade astrocytomas are not homogenous groups of tumors, and this is associated with the heterogeneity of clinical manifestation, image characteristics, and histopathological findings. Molecular studies may explain the tumor heterogeneity in the near future.

  20. An optical color image watermarking scheme by using compressive sensing with human visual characteristics in gyrator domain

    Science.gov (United States)

    Liansheng, Sui; Bei, Zhou; Zhanmin, Wang; Ailing, Tian

    2017-05-01

    A novel optical color image watermarking scheme considering human visual characteristics is presented in gyrator transform domain. Initially, an appropriate reference image is constructed of significant blocks chosen from the grayscale host image by evaluating visual characteristics such as visual entropy and edge entropy. Three components of the color watermark image are compressed based on compressive sensing, and the corresponding results are combined to form the grayscale watermark. Then, the frequency coefficients of the watermark image are fused into the frequency data of the gyrator-transformed reference image. The fused result is inversely transformed and partitioned, and eventually the watermarked image is obtained by mapping the resultant blocks into their original positions. The scheme can reconstruct the watermark with high perceptual quality and has the enhanced security due to high sensitivity of the secret keys. Importantly, the scheme can be implemented easily under the framework of double random phase encoding with the 4f optical system. To the best of our knowledge, it is the first report on embedding the color watermark into the grayscale host image which will be out of attacker's expectation. Simulation results are given to verify the feasibility and its superior performance in terms of noise and occlusion robustness.

  1. Cerebral sparganosis in children: epidemiological, clinical and MR imaging characteristics

    Directory of Open Access Journals (Sweden)

    Gong Caigui

    2012-09-01

    Full Text Available Abstract Background Cerebral sparganosis in children is an extremely rare disease of central nervous system, and caused by a tapeworm larva from the genus of Spirometra. In this study, we discussed and summarized epidemiological, clinical and MR imaging characteristics of eighteen children with cerebral sparganosis for a better diagnosis and treatment of the disease. Methods Eighteen children with cerebral sparganosis verified by pathology, serological tests and MR presentations were retrospectively investigated, and the epidemiologic and clinical characteristics of the disease were studied. Results Twenty-seven lesions were found in the eighteen children. Twelve lesions in twelve patients were solitary while the lesions in the rest six patients were multiple and asymmetrical. The positions of the lesions were: seven in frontal, eleven in parietal, four in temporal and two in occipital lobes, one in basal ganglia, one in cerebella hemisphere and one in pons. The lesions were presented as slight hypointensity on T1-weighted images but moderate hyperintensity on T2-weighted images with perilesional brain parenchyma edema. Enhanced MR scans by using Gadopentetic Acid Dimeglumine Salt were performed in the patients, and the images demonstrated abnormal enhancements with the patterns of a peripheral ring, or a tortuous beaded, or a serpiginous tubular shape. Follow-up MR scans were preformed for eight patients, and three out of the eight cases exposed migrations and changes in shapes of the lesion areas. Conclusions The MR presentations in our study in general were similar to those in previous studies. However serpiginous tubular and comma-shaped enhancements of lesions have not been previously reported. The enhanced MR imaging and follow-up MR scans with the positive results from serological tests are the most important methods for the clinical diagnosis of cerebral sparganosis in children.

  2. Imaging characteristics of intraparenchymal schwannoma and the related pathology

    International Nuclear Information System (INIS)

    Liu Shuyong; Geng Daoying; He Huijin

    2007-01-01

    Objective: To Analyze the imaging characteristics of intraparenchymal schwannoma and the related pathology, in order to improve the accuracy of diagnosis and be in favor of the clinics and the prognosis. Methods: Four cases were confirmed to be intraparenchymal schwannoma by pathological and immunohistochemistry examination. One case was examined with precontrast and enhanced CT scanning, one with unenhanced MRI scanning, two with unenhanced and enhanced CT and MRI scanning. Their images were retrospectively analyzed. Results: Of the four cases, three patients were less than 30 years old, with tumors located supratentorially. Cysts were found in all cases, with nodules on the wall in 3 cases. The nodules were enhanced markedly in two cases and moderately in one case. In addition, calcification was detected in one case and prominent peritumoral edema existed in 1 case. The picture of the pathology demonstrated Antoni type A and Antoni type B. Immunostaining showed intense immunoreactivity for S-100 protein and Vim and negative immunoreactivity for GFAP and EMA. Conclusions: Intraparenchymal schwannoma mostly occurred in juvenile, which located supratentorially in most cases. The presence of a cyst and peritumoral edema together with the tumor appears to be characteristic of intraparenchymal schwannoma. Calcification or the enhanced nodule is the helpful sign for the diagnosis. Combining the imaging findings with the pathology and immunohistochemistry results can gain the accurate diagnosis. (authors)

  3. BCGitis and BCGosis in children with primary immunodeficiency - imaging characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Shrot, Shai; Soudack, Michalle [Sheba Medical Center, Department of Diagnostic Imaging, Ramat-Gan (Israel); Tel Aviv University, Sackler School of Medicine, Tel Aviv (Israel); Barkai, Galia [Sheba Medical Center, Pediatric Infectious Diseases Unit, Safra Children' s Hospital, Tel-Hashomer (Israel); Ben-Shlush, Aviva [Sheba Medical Center, Department of Diagnostic Imaging, Ramat-Gan (Israel)

    2016-02-15

    When administered to an immune-compromised patient, BCG (Bacille Calmette-Guerin) can cause disseminated and life-threatening infections. To describe the imaging findings in children with primary immunodeficiency and BCG-related infections. We reviewed the imaging findings of children with primary immunodeficiency treated at a children's hospital during 2012-2014 with localized or disseminated BCG infection. Imaging modalities included US, CT and radiography. Nine children with primary immunodeficiency had clinical signs of post-vaccination BCGitis; seven of these children showed disseminated disease and two showed only regional lesions with characteristic ipsilateral lymphadenopathy. Overall, lymphadenopathy was the most prevalent feature (n = 8) and characteristically appeared as a ring-enhancing hypodense (CT) or hypoechoic (US) lesion. Visceral involvement with multiple abscesses appeared in the spleen (n = 2), liver (n = 1) and bones (n = 1). All lesions regressed following appropriate anti-tuberculosis treatment. BCG infection needs to be considered in children with typical findings and with suspected primary immunodeficiency. (orig.)

  4. Diverse Imaging characteristics of a mandibular intraosseous vascular lesion

    International Nuclear Information System (INIS)

    Handa, Hina; Naidu, Giridhar S.; Dara, Balaji Gandhi Babu; Deshpande, Ashwini; Raghavendra, Raju

    2014-01-01

    Intraosseous vascular lesions of the maxillofacial region are rare, and the differential diagnosis of intraosseous vascular malformations from other jaw lesions can be challenging. In the present case, magnetic resonance imaging and three-dimensional computed tomographic angiography (CTA) was used for diagnosis, and the lesion was treated with surgical excision. Diverse characteristics such as the 'honeycomb' and 'sunburst' radiographic appearances and the absence of major peripheral feeder vessels in the CTA were noted. Intraosseous vascular malformations have a varied radiographic appearance, and the nomenclature of these lesions is equally diverse, with several overlapping terms. Pathologists do not generally differentiate among intraosseous vascular lesions on the basis of histopathology, although these lesions may present with contrasting immunohistochemical and clinical behaviors requiring varied treatment strategies. This case report highlights the need for multiple imaging modalities to differentiate among vascular lesions, as well as to better understand the behaviors of these unique lesions.

  5. Imaging characteristics of meningiomas in Yemen - impact of Khat abuse

    International Nuclear Information System (INIS)

    Alansi, M.

    2011-01-01

    Intracranial meningiomas are the most common tumor derived from non-neural epithelial tissues, accounting for 13% to 26% of all intracranial tumors. In Yemen, several epidemiological studies have showed an increasing rate of meningiomas during the last 15-20 years. This can be explained by the influence of specific epidemiological factors (racial, genetic, toxic, etc) as well as, noticeably improved diagnostic imaging. A specific risk factor for Yemeni sub-population groups is chronic use of Khat (Catha Edulis Forskal, CE ) - an amphetamine-like product, associated with a variety of serious health, social and economic problems. The present study analyzed the imaging characteristics of meningiomas in Yemeni patients, who systematically use CE, compared to those who never consume it.

  6. Magnetic resonance imaging characteristics of fibrocystic change of the breast.

    Science.gov (United States)

    van den Bosch, Maurice A A J; Daniel, Bruce L; Mariano, Michelle N; Nowels, Kent N; Birdwell, Robyn L; Fong, Kathy J; Desmond, Pam S; Plevritis, Sylvia; Stables, Lara A; Zakhour, Marowan; Herfkens, Robert J; Ikeda, Debra M

    2005-07-01

    The objective of this study was to identify magnetic resonance imaging (MRI) characteristics of fibrocystic change (FCC) of the breast. Fourteen patients with a histopathologic diagnosis of solitary FCC of the breast underwent x-ray mammography and MRI of the breast. Three experienced breast imaging radiologists retrospectively reviewed the MRI findings and categorized the lesions on morphologic and kinetic criteria according to the ACR BI-RADS-MRI Lexicon. The most striking morphologic feature of fibrocystic change was nonmass-like regional enhancement found in 6 of 14 (43%) FCC lesions. Based on morphologic criteria alone, 12 of 14 (86%) lesions were correctly classified as benign. According to analysis of the time-intensity curves, 10 of 14 (71%) FCC lesions were correctly classified as benign. Although FCC has a wide spectrum of morphologic and kinetic features on MRI, it most often presents as a mass or a nonmass-like regional enhancing lesion with benign enhancement kinetics.

  7. Clinical and imaging characteristics of the vascular dementia. Preliminary studies

    International Nuclear Information System (INIS)

    Gomez Viera, Nelson; Rivero Arias, Edmundo; Perez Nellar, Jesus; Begueria Santos, Ramon; Arias Sifontes, William; Raiteris Flores, Juan

    1997-01-01

    A descriptive prospective study was carried out in 41 patients presenting with vascular dementia from Habana Vieja municipality, Havana City, in order to know some of the clinical and imaging characteristics of this disease. The main risk factors observed were the history of cerebrovascular disease and arterial hypertension. Depression, sleeping disorders and focal and pseudo bulbar neurologic signs were the most frequent clinical findings. Folstein neuropsychological test evidenced an important disorder of attention, calculation, the evocation memory and orientation. According to this test, 29 % of the patients had a severe dementia and nearly 50 % showed a severe handicap. The most frequent imaging findings observed in the computerized axial tomography of the cranium were cerebral atrophy, and single or multiple infarctions. Multiple cerebral infarctions, the lacunar status, subcortical encephalopathy of Binswanger, and single infarction located in cerebral areas related to cognition were considered as possible psychopathological mechanisms associated with the disease

  8. The characteristics of SPECT images in childhood benign partial epilepsy

    International Nuclear Information System (INIS)

    Jia Shaowei; Liao Jianxiang; Liu Xiaoyan; Zheng Xiyuan; Qin Jiong; Pan Zhongyun; Zuo Qihua

    1998-01-01

    Purpose: To investigate childhood benign partial epilepsy (BPE) with SPECT. Methods: Double SPECT imaging was performed on 21 cases of BPE at the stage of wake (interval spike discharge) and sleep (spike discharge), under EEG monitoring. The transverse images were reconstructed after digital image subtraction. The quantitative analysis was conducted with brain flow change rate (BFCR) % mathematical model. Results: EEG monitoring demonstrated approximately normal background of 21 cases of BPE during the stage of wake, and spike discharge frequency markedly increased during the stage of sleep, 117 foci were showed by SPeCT in cases of BPE, and the average was 5.6 +- 1.6 foci/case. The characteristics of SPECT transverse images were 1) multiple foci of mirror, 2) mostly seen in Rolandic region, 3) circular symbol, 4) the radioactivity in foci decreased during the stage of wake (interval spike discharge) and increased during the stage of sleep (spike discharge). The concordance of SPECT and EEG was 93.1% (109/117 foci). The BFCR% of all epileptogenic foci exceeded normal limit (99% confidence interval). There was no correlation between the spike discharge frequency and BFCR% (r = 0.45, P>0.05). Conclusions: Regional cerebral blood flow and function were abnormal during the epileptogenic foci were discharging abnormally in BPE

  9. Dynamic image characteristics of pulmonary tuberculosis with diabetes mellitus

    International Nuclear Information System (INIS)

    Zhou Xinhua

    2000-01-01

    Objective: To analyze image characteristics of pulmonary tuberculosis associated with diabetes mellitus and observe the changes of pulmonary tuberculotic lesions influenced by the state of hyperglycosemia. Methods: Examinations of chest plain film and tomography were taken in 68 patients with pulmonary tuberculosis and diabetes, and additional CT scans were done in 38 patients among them. Radiological examinations of lung and blood sugar test were taken at the interval of 2, 3, and 4-6 months in all 68 patients under the treatment of regular blood sugar control and antituberculosis, which compared with 30 patients with pulmonary tuberculosis only. Results: The images of X-ray and CT showed major lesions of massive patchy shadow in 55 patients (80.9%), or multiple small patchy shadow in 13(19.1%) and cavity 61(89.7%). After 2 month's treatment, enlargement of patchy shadow and cavity were found in 9(23.7%)and 10(28.6%)cases, respectively with overall deterioration rates of 65.8% in group of 38 patients with level of blood sugar over 7.0 mmol/L, which was significantly higher than that of the control group 7.0 mmol/L(x 2 =16.4, P 2 = 0.81, P>0.5) with the well controlled blood sugar after treatment of 3 months or more. The follow-up images showed similar results between the groups of pulmonary tuberculosis only and the group of pulmonary tuberculosis with high level of blood sugar, in which the overall deterioration rates was significant less than the group of pulmonary tuberculosis with level of blood sugar more than 8.0 mmol/L(x 2 =5.46, P<0.025). Conclusion: There are imaging characteristics in patient with pulmonary tuberculosis and diabetes mellitus. The state of hyperglycosemia is a vital factor, which influences the radiological changes of pulmonary tuberculosis

  10. High-resolution, time-resolved MRA provides superior definition of lower-extremity arterial segments compared to 2D time-of-flight imaging.

    Science.gov (United States)

    Thornton, F J; Du, J; Suleiman, S A; Dieter, R; Tefera, G; Pillai, K R; Korosec, F R; Mistretta, C A; Grist, T M

    2006-08-01

    To evaluate a novel time-resolved contrast-enhanced (CE) projection reconstruction (PR) magnetic resonance angiography (MRA) method for identifying potential bypass graft target vessels in patients with Class II-IV peripheral vascular disease. Twenty patients (M:F = 15:5, mean age = 58 years, range = 48-83 years), were recruited from routine MRA referrals. All imaging was performed on a 1.5 T MRI system with fast gradients (Signa LX; GE Healthcare, Waukesha, WI). Images were acquired with a novel technique that combined undersampled PR with a time-resolved acquisition to yield an MRA method with high temporal and spatial resolution. The method is called PR hyper time-resolved imaging of contrast kinetics (PR-hyperTRICKS). Quantitative and qualitative analyses were used to compare two-dimensional (2D) time-of-flight (TOF) and PR-hyperTRICKS in 13 arterial segments per lower extremity. Statistical analysis was performed with the Wilcoxon signed-rank test. Fifteen percent (77/517) of the vessels were scored as missing or nondiagnostic with 2D TOF, but were scored as diagnostic with PR-hyperTRICKS. Image quality was superior with PR-hyperTRICKS vs. 2D TOF (on a four-point scale, mean rank = 3.3 +/- 1.2 vs. 2.9 +/- 1.2, P < 0.0001). PR-hyperTRICKS produced images with high contrast-to-noise ratios (CNR) and high spatial and temporal resolution. 2D TOF images were of inferior quality due to moderate spatial resolution, inferior CNR, greater flow-related artifacts, and absence of temporal resolution. PR-hyperTRICKS provides superior preoperative assessment of lower limb ischemia compared to 2D TOF.

  11. Language development at 2 years is correlated to brain microstructure in the left superior temporal gyrus at term equivalent age: a diffusion tensor imaging study.

    Science.gov (United States)

    Aeby, Alec; De Tiège, Xavier; Creuzil, Marylise; David, Philippe; Balériaux, Danielle; Van Overmeire, Bart; Metens, Thierry; Van Bogaert, Patrick

    2013-09-01

    This study aims at testing the hypothesis that neurodevelopmental abilities at age 2 years are related with local brain microstructure of preterm infants at term equivalent age. Forty-one preterm infants underwent brain MRI with diffusion tensor imaging sequences to measure mean diffusivity (MD), fractional anisotropy (FA), longitudinal and transverse diffusivity (λ// and λ[perpendicular]) at term equivalent age. Neurodevelopment was assessed at 2 years corrected age using the Bayley III scale. A voxel-based analysis approach, statistical parametric mapping (SPM8), was used to correlate changes of the Bayley III scores with the regional distribution of MD, FA, λ// and λ[perpendicular]. We found that language abilities are negatively correlated to MD, λ// and λ[perpendicular] in the left superior temporal gyrus in preterm infants. These findings suggest that higher MD, λ// and λ[perpendicular] values at term-equivalent age in the left superior temporal gyrus are associated with poorer language scores in later childhood. Consequently, it highlights the key role of the left superior temporal gyrus for the development of language abilities in children. Further studies are needed to assess on an individual basis and on the long term the prognostic value of brain DTI at term equivalent age for the development of language. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Abnormal Degree Centrality of Bilateral Putamen and Left Superior Frontal Gyrus in Schizophrenia with Auditory Hallucinations: A Resting-state Functional Magnetic Resonance Imaging Study.

    Science.gov (United States)

    Chen, Cheng; Wang, Hui-Ling; Wu, Shi-Hao; Huang, Huan; Zou, Ji-Lin; Chen, Jun; Jiang, Tian-Zi; Zhou, Yuan; Wang, Gao-Hua

    2015-12-05

    Dysconnectivity hypothesis of schizophrenia has been increasingly emphasized. Recent researches showed that this dysconnectivity might be related to occurrence of auditory hallucination (AH). However, there is still no consistent conclusion. This study aimed to explore intrinsic dysconnectivity pattern of whole-brain functional networks at voxel level in schizophrenic with AH. Auditory hallucinated patients group (n = 42 APG), no hallucinated patients group (n = 42 NPG) and normal controls (n = 84 NCs) were analyzed by resting-state functional magnetic resonance imaging. The functional connectivity metrics index (degree centrality [DC]) across the entire brain networks was calculated and evaluated among three groups. DC decreased in the bilateral putamen and increased in the left superior frontal gyrus in all the patients. However, in APG, the changes of DC were more obvious compared with NPG. Symptomology scores were negatively correlated with the DC of bilateral putamen in all patients. AH score of APG positively correlated with the DC in left superior frontal gyrus but negatively correlated with the DC in bilateral putamen. Our findings corroborated that schizophrenia was characterized by functional dysconnectivity, and the abnormal DC in bilateral putamen and left superior frontal gyrus might be crucial in the occurrence of AH.

  13. Choroidal vasculature characteristics based choroid segmentation for enhanced depth imaging optical coherence tomography images

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Qiang; Niu, Sijie [School of Computer Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Yuan, Songtao; Fan, Wen, E-mail: fanwen1029@163.com; Liu, Qinghuai [Department of Ophthalmology, The First Affiliated Hospital with Nanjing Medical University, Nanjing 210029 (China)

    2016-04-15

    Purpose: In clinical research, it is important to measure choroidal thickness when eyes are affected by various diseases. The main purpose is to automatically segment choroid for enhanced depth imaging optical coherence tomography (EDI-OCT) images with five B-scans averaging. Methods: The authors present an automated choroid segmentation method based on choroidal vasculature characteristics for EDI-OCT images with five B-scans averaging. By considering the large vascular of the Haller’s layer neighbor with the choroid-sclera junction (CSJ), the authors measured the intensity ascending distance and a maximum intensity image in the axial direction from a smoothed and normalized EDI-OCT image. Then, based on generated choroidal vessel image, the authors constructed the CSJ cost and constrain the CSJ search neighborhood. Finally, graph search with smooth constraints was utilized to obtain the CSJ boundary. Results: Experimental results with 49 images from 10 eyes in 8 normal persons and 270 images from 57 eyes in 44 patients with several stages of diabetic retinopathy and age-related macular degeneration demonstrate that the proposed method can accurately segment the choroid of EDI-OCT images with five B-scans averaging. The mean choroid thickness difference and overlap ratio between the authors’ proposed method and manual segmentation drawn by experts were −11.43 μm and 86.29%, respectively. Conclusions: Good performance was achieved for normal and pathologic eyes, which proves that the authors’ method is effective for the automated choroid segmentation of the EDI-OCT images with five B-scans averaging.

  14. Choroidal vasculature characteristics based choroid segmentation for enhanced depth imaging optical coherence tomography images

    International Nuclear Information System (INIS)

    Chen, Qiang; Niu, Sijie; Yuan, Songtao; Fan, Wen; Liu, Qinghuai

    2016-01-01

    Purpose: In clinical research, it is important to measure choroidal thickness when eyes are affected by various diseases. The main purpose is to automatically segment choroid for enhanced depth imaging optical coherence tomography (EDI-OCT) images with five B-scans averaging. Methods: The authors present an automated choroid segmentation method based on choroidal vasculature characteristics for EDI-OCT images with five B-scans averaging. By considering the large vascular of the Haller’s layer neighbor with the choroid-sclera junction (CSJ), the authors measured the intensity ascending distance and a maximum intensity image in the axial direction from a smoothed and normalized EDI-OCT image. Then, based on generated choroidal vessel image, the authors constructed the CSJ cost and constrain the CSJ search neighborhood. Finally, graph search with smooth constraints was utilized to obtain the CSJ boundary. Results: Experimental results with 49 images from 10 eyes in 8 normal persons and 270 images from 57 eyes in 44 patients with several stages of diabetic retinopathy and age-related macular degeneration demonstrate that the proposed method can accurately segment the choroid of EDI-OCT images with five B-scans averaging. The mean choroid thickness difference and overlap ratio between the authors’ proposed method and manual segmentation drawn by experts were −11.43 μm and 86.29%, respectively. Conclusions: Good performance was achieved for normal and pathologic eyes, which proves that the authors’ method is effective for the automated choroid segmentation of the EDI-OCT images with five B-scans averaging.

  15. Medical emergencies in the imaging department of a university hospital: event and imaging characteristics.

    Science.gov (United States)

    van Tonder, F C; Sutherland, T; Smith, R J; Chock, J M E; Santamaria, J D

    2013-01-01

    We aimed to describe the characteristics of medical emergencies that occurred in the medical imaging department (MID) of a university hospital in Melbourne, Australia. A database of 'Respond Medical Emergency Team (MET)' and 'Respond Blue' calls was retrospectively examined for the period June 2003 to November 2010 in relation to events that occurred in the MID. The hospital medical imaging database was also examined in relation to these events and, where necessary, patients' notes were reviewed. Ethics approval was granted by the hospital ethics review board. There were 124 medical emergency calls in the MID during the study period, 28% Respond Blue and 72% Respond MET. Of these 124 calls, 26% occurred outside of usual work hours and 12% involved cardiac arrest. The most common reasons for the emergency calls were seizures (14%) and altered conscious state (13%). Contrast anaphylaxis precipitated the emergency in 4% of cases. In 83% of cases the emergency calls were for patients attending the MID for diagnostic imaging, the remainder being for a procedure. Of the scheduled imaging techniques, 45% were for computed tomography. The scheduled imaging was abandoned due to the emergency in 12% of cases. When performed, imaging informed patient management in 34% of cases in diagnostic imaging and in all cases in the context of image-guided procedures. Medical emergency calls in the MID often occurred outside usual work hours and were attributed to a range of medical problems. The emergencies occurred in relation to all imaging techniques and imaging informed patient management in many cases. Crown Copyright © 2012. Published by Elsevier Ireland Ltd. All rights reserved.

  16. Characteristics of a multi-image camera on a CT image

    International Nuclear Information System (INIS)

    Mihara, Kazuhiro; Fujino, Tatsuo; Abe, Katsuhito

    1984-01-01

    A multi-imaging camera was used for obtaining a hard-copy image from an imaging device of a CT scanner. The contrast and brightness of the CRT and time exposure of the camera were the three important factors which influenced the quality of the hard-copy image. Two kinds of original test patterns were designed to examine the characteristics of the factors. One was the grayscale test pattern which was used to obtain the density curve. This curve, named the Film-CRT curve, (F-C curve) is to distinguish it from the H D curve. The other was the sharpness test pattern which was used to examine the relationship between brightness and sharpness. As a result, the slope of F-C curve became steeper with a decrease in brightness, with an increase in contrast and with increase in exposure time. Sharpness became worse with an increase in brightness. Therefore, to obtain a good hard copy image, the brightness must be set as dark as possible, and the contrast and exposure time must be controlled after due consideration is given to their characteristics. (author)

  17. Optimization of CMOS image sensor utilizing variable temporal multisampling partial transfer technique to achieve full-frame high dynamic range with superior low light and stop motion capability

    Science.gov (United States)

    Kabir, Salman; Smith, Craig; Armstrong, Frank; Barnard, Gerrit; Schneider, Alex; Guidash, Michael; Vogelsang, Thomas; Endsley, Jay

    2018-03-01

    Differential binary pixel technology is a threshold-based timing, readout, and image reconstruction method that utilizes the subframe partial charge transfer technique in a standard four-transistor (4T) pixel CMOS image sensor to achieve a high dynamic range video with stop motion. This technology improves low light signal-to-noise ratio (SNR) by up to 21 dB. The method is verified in silicon using a Taiwan Semiconductor Manufacturing Company's 65 nm 1.1 μm pixel technology 1 megapixel test chip array and is compared with a traditional 4 × oversampling technique using full charge transfer to show low light SNR superiority of the presented technology.

  18. Superiority of 18F-FNa PET/CT for Detecting Bone Metastases in Comparison with Other Diagnostic Imaging Modalities

    OpenAIRE

    Paula Lapa; Tiago Saraiva; Rodolfo Silva; Margarida Marques; Gracinda Costa; João Pedroso Lima

    2017-01-01

    Introduction: The 18F-NaF positron emission tomography/computed tomography is being considered as an excellent imaging modality for bone metastases detection. This ability was compared with other imaging techniques. Material and Methods: We retrospectively evaluated 114 patients who underwent 18F-NaF positron emission tomography/ computed tomography. Of these, 49 patients also had bone scintigraphy, 61 18F-FDG positron emission tomography/computed tomography and 10 18F-FCH positron emis...

  19. Effect of scatter media on small gamma camera imaging characteristics

    International Nuclear Information System (INIS)

    Ser, H. K.; Choi, Y.; Yim, K. C.

    2001-01-01

    Effect of scatter media materials and thickness, located between radioactivity and small gamma camera, on imaging characteristics was evaluated. The small gamma camera developed for breast imaging was consisted of collimator, NaI(TI) crystal (60x60x6 mm 3 ). PSPMT (position sensitive photomultiplier tube), NIMs and personal computer. Monte Carlo simulation was performed to evaluate the system sensitivity with different scatter media thickness (0∼8 cm) and materials (air and acrylie) with parallel hole collimator and diverging collimator. The sensitivity and spatial resolution was measured using the small gamma camera with the same condition applied to the simulation. Counts was decreased by 10% (air) and 54% (acrylic) with the parallel hole collimator and by 35% (air) and 63% (acrylic) with the diverging collimator. Spatial resolution was decreased as increasing the thickness of scatter media. This study substantiate the importance of a gamma camera positioning and the minimization of the distance between detector and target lesion in the clinical application of a gamma camera

  20. ANALYSIS OF CAMOUFLAGE COVER SPECTRAL CHARACTERISTICS BY IMAGING SPECTROMETER

    Directory of Open Access Journals (Sweden)

    A. Y. Kouznetsov

    2016-03-01

    Full Text Available Subject of Research.The paper deals with the problems of detection and identification of objects in hyperspectral imagery. The possibility of object type determination by statistical methods is demonstrated. The possibility of spectral image application for its data type identification is considered. Method. Researching was done by means of videospectral equipment for objects detection at "Fregat" substrate. The postprocessing of hyperspectral information was done with the use of math model of pattern recognition system. The vegetation indexes TCHVI (Three-Channel Vegetation Index and NDVI (Normalized Difference Vegetation Index were applied for quality control of object recognition. Neumann-Pearson criterion was offered as a tool for determination of objects differences. Main Results. We have carried out analysis of the spectral characteristics of summer-typecamouflage cover (Germany. We have calculated the density distribution of vegetation indexes. We have obtained statistical characteristics needed for creation of mathematical model for pattern recognition system. We have shown the applicability of vegetation indices for detection of summer camouflage cover on averdure background. We have presented mathematical model of object recognition based on Neumann-Pearson criterion. Practical Relevance. The results may be useful for specialists in the field of hyperspectral data processing for surface state monitoring.

  1. Altered activity and functional connectivity of superior temporal gyri in anxiety disorders: A functional magnetic resonance imaging study

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Xiaohu; Xi, Qian; Wang, Peijun; Li, Chunbo [Tong Ji Hospital of Tong Ji University, Shanghai (China); He, Hongjian [Bio-X lab, Dept. of Physics, Zhe Jiang University, Hangzhou (China)

    2014-08-15

    The prior functional MRI studies have demonstrated significantly abnormal activity in the bilateral superior temporal gyrus (STG) of anxiety patients. The purpose of the current investigation was to determine whether the abnormal activity in these regions was related to a loss of functional connectivity between these regions. Ten healthy controls and 10 anxiety patients underwent noninvasive fMRI while actively listening to emotionally neutral words alternated by silence (Task 1) or threat-related words (Task 2). The participants were instructed to silently make a judgment of each word's valence (i.e., unpleasant, pleasant, or neutral). A coherence analysis was applied to the functional MRI data to examine the functional connectivity between the left and the right STG, which was selected as the primary region of interest on the basis of our prior results. The data demonstrated that the anxiety patients exhibited significantly increased activation in the bilateral STG than the normal controls. The functional connectivity analysis indicated that the patient group showed significantly decreased degree of connectivity between the bilateral STG during processing Task 2 compared to Task 1 (t = 2.588, p = 0.029). In addition, a significantly decreased connectivity was also observed in the patient group compared to the control group during processing Task 2 (t = 2.810, p = 0.012). Anxiety patients may exhibit increased activity of the STG but decreased functional connectivity between the left and right STG, which may reflect the underlying neural abnormality of anxiety disorder, and this will provide new insights into this disease.

  2. Altered activity and functional connectivity of superior temporal gyri in anxiety disorders: A functional magnetic resonance imaging study

    International Nuclear Information System (INIS)

    Zhao, Xiaohu; Xi, Qian; Wang, Peijun; Li, Chunbo; He, Hongjian

    2014-01-01

    The prior functional MRI studies have demonstrated significantly abnormal activity in the bilateral superior temporal gyrus (STG) of anxiety patients. The purpose of the current investigation was to determine whether the abnormal activity in these regions was related to a loss of functional connectivity between these regions. Ten healthy controls and 10 anxiety patients underwent noninvasive fMRI while actively listening to emotionally neutral words alternated by silence (Task 1) or threat-related words (Task 2). The participants were instructed to silently make a judgment of each word's valence (i.e., unpleasant, pleasant, or neutral). A coherence analysis was applied to the functional MRI data to examine the functional connectivity between the left and the right STG, which was selected as the primary region of interest on the basis of our prior results. The data demonstrated that the anxiety patients exhibited significantly increased activation in the bilateral STG than the normal controls. The functional connectivity analysis indicated that the patient group showed significantly decreased degree of connectivity between the bilateral STG during processing Task 2 compared to Task 1 (t = 2.588, p = 0.029). In addition, a significantly decreased connectivity was also observed in the patient group compared to the control group during processing Task 2 (t = 2.810, p = 0.012). Anxiety patients may exhibit increased activity of the STG but decreased functional connectivity between the left and right STG, which may reflect the underlying neural abnormality of anxiety disorder, and this will provide new insights into this disease.

  3. Characteristics of different frequency ranges in scanning electron microscope images

    International Nuclear Information System (INIS)

    Sim, K. S.; Nia, M. E.; Tan, T. L.; Tso, C. P.; Ee, C. S.

    2015-01-01

    We demonstrate a new approach to characterize the frequency range in general scanning electron microscope (SEM) images. First, pure frequency images are generated from low frequency to high frequency, and then, the magnification of each type of frequency image is implemented. By comparing the edge percentage of the SEM image to the self-generated frequency images, we can define the frequency ranges of the SEM images. Characterization of frequency ranges of SEM images benefits further processing and analysis of those SEM images, such as in noise filtering and contrast enhancement

  4. Characteristics of different frequency ranges in scanning electron microscope images

    Energy Technology Data Exchange (ETDEWEB)

    Sim, K. S., E-mail: kssim@mmu.edu.my; Nia, M. E.; Tan, T. L.; Tso, C. P.; Ee, C. S. [Faculty of Engineering and Technology, Multimedia University, 75450 Melaka (Malaysia)

    2015-07-22

    We demonstrate a new approach to characterize the frequency range in general scanning electron microscope (SEM) images. First, pure frequency images are generated from low frequency to high frequency, and then, the magnification of each type of frequency image is implemented. By comparing the edge percentage of the SEM image to the self-generated frequency images, we can define the frequency ranges of the SEM images. Characterization of frequency ranges of SEM images benefits further processing and analysis of those SEM images, such as in noise filtering and contrast enhancement.

  5. Gadolinium-Enhanced Three-Dimensional Magnetization - Prepared Rapid Gradient-Echo (3D MP-RAGE) Imaging is Superior to Spin-Echo Imaging in Delineating Brain Metastases

    International Nuclear Information System (INIS)

    Takeda, T.; Takeda, A.; Nagaoka, T.; Kunieda, E.; Takemasa, K.; Watanabe, M.; Hatou, T.; Oguro, S.; Katayama, M.

    2008-01-01

    Background: Precisely defining the number and location of brain metastases is very important for establishing a treatment strategy for malignancies. Although magnetic resonance imaging (MRI) is now considered the best modality, various improvements in sequences are still being made. Purpose: To prospectively compare the diagnostic ability of three-dimensional, magnetization-prepared rapid gradient-echo (3D MP-RAGE) imaging in detecting metastatic brain tumors, with that of two-dimensional spin-echo (2D SE) T1-weighted imaging. Material and Methods: A total of 123 examinations were included in this study, and 119 examinations from 88 patients with known malignancies were analyzed. All patients underwent T1- and T2-weighted 2D SE transverse imaging, followed by gadolinium-enhanced T1-weighted transverse and coronal 2D SE imaging and 3D MP-RAGE transverse imaging. Four radiologists interpreted the images to compare the accuracy and the time required for interpretation for each imaging. Results: 3D MP-RAGE imaging was significantly better than 2D SE imaging for detecting metastatic brain lesions, regardless of the readers' experience. The sensitivities of the 3D MP-RAGE and 2D SE imaging for all observers were 0.81 vs. 0.80 (P>0.05), specificities were 0.93 vs. 0.87 (P 0.05), and accuracies were 0.84 vs. 0.78 (P<0.05), respectively. There was no significant difference in the time required for image interpretation between the two modalities (15.6±4.0 vs. 15.4±4.1 min). Conclusion: 3D MP-RAGE imaging proved superior to 2D SE imaging in the detection of brain metastases

  6. The Superior Fronto-Occipital Fasciculus in the Human Brain Revealed by Diffusion Spectrum Imaging Tractography: An Anatomical Reality or a Methodological Artifact?

    Science.gov (United States)

    Bao, Yue; Wang, Yong; Wang, Wei; Wang, Yibao

    2017-01-01

    The existence of the superior fronto-occipital fasciculus (SFOF) in the human brain remains controversial. The aim of the present study was to clarify the existence, course, and terminations of the SFOF. High angular diffusion spectrum imaging (DSI) analysis was performed on six healthy adults and on a template of 842 subjects from the Human Connectome Project. To verify tractography results, we performed fiber microdissections of four post-mortem human brains. Based on DSI tractography, we reconstructed the SFOF in the subjects and the template from the Human Connectome Project that originated from the rostral and medial parts of the superior and middle frontal gyri. By tractography, we found that the fibers formed a compact fascicle at the level of the anterior horn of the lateral ventricle coursing above the head of caudate nucleus, medial to the corona radiate and under the corpus callosum (CC), and terminated at the parietal region via the lower part of the caudate nucleus. We consider that this fiber bundle observed by tractography is the SFOF, although it terminates mainly at the parietal region, rather than occipital lobe. By contrast, we were unable to identify a fiber bundle corresponding to the SFOF in our fiber dissection study. Although we did not provide definite evidence of the SFOF in the human brain, these findings may be useful for future studies in this field. PMID:29321729

  7. The Superior Fronto-Occipital Fasciculus in the Human Brain Revealed by Diffusion Spectrum Imaging Tractography: An Anatomical Reality or a Methodological Artifact?

    Directory of Open Access Journals (Sweden)

    Yue Bao

    2017-12-01

    Full Text Available The existence of the superior fronto-occipital fasciculus (SFOF in the human brain remains controversial. The aim of the present study was to clarify the existence, course, and terminations of the SFOF. High angular diffusion spectrum imaging (DSI analysis was performed on six healthy adults and on a template of 842 subjects from the Human Connectome Project. To verify tractography results, we performed fiber microdissections of four post-mortem human brains. Based on DSI tractography, we reconstructed the SFOF in the subjects and the template from the Human Connectome Project that originated from the rostral and medial parts of the superior and middle frontal gyri. By tractography, we found that the fibers formed a compact fascicle at the level of the anterior horn of the lateral ventricle coursing above the head of caudate nucleus, medial to the corona radiate and under the corpus callosum (CC, and terminated at the parietal region via the lower part of the caudate nucleus. We consider that this fiber bundle observed by tractography is the SFOF, although it terminates mainly at the parietal region, rather than occipital lobe. By contrast, we were unable to identify a fiber bundle corresponding to the SFOF in our fiber dissection study. Although we did not provide definite evidence of the SFOF in the human brain, these findings may be useful for future studies in this field.

  8. Casein-Coated Fe5C2 Nanoparticles with Superior r2 Relaxivity for Liver-Specific Magnetic Resonance Imaging.

    Science.gov (United States)

    Cowger, Taku A; Tang, Wei; Zhen, Zipeng; Hu, Kai; Rink, David E; Todd, Trever J; Wang, Geoffrey D; Zhang, Weizhong; Chen, Hongmin; Xie, Jin

    2015-01-01

    Iron oxide nanoparticles have been extensively used as T2 contrast agents for liver-specific magnetic resonance imaging (MRI). The applications, however, have been limited by their mediocre magnetism and r2 relaxivity. Recent studies show that Fe5C2 nanoparticles can be prepared by high temperature thermal decomposition. The resulting nanoparticles possess strong and air stable magnetism, suggesting their potential as a novel type of T2 contrast agent. To this end, we improve the synthetic and surface modification methods of Fe5C2 nanoparticles, and investigated the impact of size and coating on their performances for liver MRI. Specifically, we prepared 5, 14, and 22 nm Fe5C2 nanoparticles and engineered their surface by: 1) ligand addition with phospholipids, 2) ligand exchange with zwitterion-dopamine-sulfonate (ZDS), and 3) protein adsorption with casein. It was found that the size and surface coating have varied levels of impact on the particles' hydrodynamic size, viability, uptake by macrophages, and r2 relaxivity. Interestingly, while phospholipid- and ZDS-coated Fe5C2 nanoparticles showed comparable r2, the casein coating led to an r2 enhancement by more than 2 fold. In particular, casein coated 22 nm Fe5C2 nanoparticle show a striking r2 of 973 mM(-1)s(-1), which is one of the highest among all of the T2 contrast agents reported to date. Small animal studies confirmed the advantage of Fe5C2 nanoparticles over iron oxide nanoparticles in inducing hypointensities on T2-weighted MR images, and the particles caused little toxicity to the host. The improvements are important for transforming Fe5C2 nanoparticles into a new class of MRI contrast agents. The observations also shed light on protein-based surface modification as a means to modulate contrast ability of magnetic nanoparticles.

  9. Orthogonal polarization spectral (OPS) imaging and topographical characteristics of oral squamous cell carcinoma

    NARCIS (Netherlands)

    Lindeboom, Jerome A.; Mathura, Keshen R.; Ince, Can

    2006-01-01

    Tumor microcirculatory characteristics until now have only been assessed by histological examination of biopsies or invasive imaging technique. The recent introduction of orthogonal polarization spectral (OPS) imaging as a new tool for in vivo visualization of human microcirculation makes it

  10. Detection of microcalcifications by characteristic magnetic susceptibility effects using MR phase image cross-correlation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Baheza, Richard A. [Department of Biomedical Engineering and Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee 37232-2310 (United States); Welch, E. Brian [Institute of Imaging Science and Departments of Radiology and Radiological Sciences and Biomedical Engineering, Vanderbilt University, Nashville, Tennessee 37232-2310 (United States); Gochberg, Daniel F. [Institute of Imaging Science and Departments of Radiology and Radiological Sciences, and Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37232-2310 (United States); Sanders, Melinda [Department of Pathology, Vanderbilt University, Nashville, Tennessee 37232-2310 (United States); Harvey, Sara [Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee 37232-2310 (United States); Gore, John C. [Institute of Imaging Science and Departments of Biomedical Engineering, Radiology and Radiological Sciences, Physics and Astronomy, and Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee 37232-2310 (United States); Yankeelov, Thomas E., E-mail: thomas.yankeelov@vanderbilt.edu [Institute of Imaging Science and Departments of Radiology and Radiological Sciences, Biomedical Engineering, Physics and Astronomy, and Cancer Biology, Vanderbilt University, Nashville, Tennessee 37232-2310 (United States)

    2015-03-15

    Purpose: To develop and evaluate a new method for detecting calcium deposits using their characteristic magnetic susceptibility effects on magnetic resonance (MR) images at high fields and demonstrate its potential in practice for detecting breast microcalcifications. Methods: Characteristic dipole signatures of calcium deposits were detected in magnetic resonance phase images by computing the cross-correlation between the acquired data and a library of templates containing simulated phase patterns of spherical deposits. The influence of signal-to-noise ratio and various other MR parameters on the results were assessed using simulations and validated experimentally. The method was tested experimentally for detection of calcium fragments within gel phantoms and calcium-like inhomogeneities within chicken tissue at 7 T with optimized MR acquisition parameters. The method was also evaluated for detection of simulated microcalcifications, modeled from biopsy samples of malignant breast cancer, inserted in silico into breast magnetic resonance imaging (MRIs) of healthy subjects at 7 T. For both assessments of calcium fragments in phantoms and biopsy-based simulated microcalcifications in breast MRIs, receiver operator characteristic curve analyses were performed to determine the cross-correlation index cutoff, for achieving optimal sensitivity and specificity, and the area under the curve (AUC), for measuring the method’s performance. Results: The method detected calcium fragments with sizes of 0.14–0.79 mm, 1 mm calcium-like deposits, and simulated microcalcifications with sizes of 0.4–1.0 mm in images with voxel sizes between (0.2 mm){sup 3} and (0.6 mm){sup 3}. In images acquired at 7 T with voxel sizes of (0.2 mm){sup 3}–(0.4 mm){sup 3}, calcium fragments (size 0.3–0.4 mm) were detected with a sensitivity, specificity, and AUC of 78%–90%, 51%–68%, and 0.77%–0.88%, respectively. In images acquired with a human 7 T scanner, acquisition times below 12

  11. Intracranially protruded bilateral posterior and superior SCCs with multiple dehiscences in a patient with positional vertigo: CT and MR imaging findings and review of literature

    International Nuclear Information System (INIS)

    Kundaragi, Nischal G; Mudali, Srinivasa; Karpagam, Bulabai; Priya, Rathna

    2014-01-01

    We report a rare case of intracranially protruded posterior and superior semicircular canals beyond the margins of temporal bone with bony roof dehiscence in bilateral posterior and left superior semicircular canals in a patient with benign paroxysmal positional vertigo (BPPV)

  12. T2-weighted images are superior to other MR image types for the determination of diffuse intrinsic pontine glioma intratumoral heterogeneity.

    Science.gov (United States)

    Harward, Stephen; Harrison Farber, S; Malinzak, Michael; Becher, Oren; Thompson, Eric M

    2018-03-01

    Diffuse intrinsic pontine glioma (DIPG) remains the main cause of death in children with brain tumors. Given the inefficacy of numerous peripherally delivered agents to treat DIPG, convection enhanced delivery (CED) of therapeutic agents is a promising treatment modality. The purpose of this study was to determine which MR imaging type provides the best discrimination of intratumoral heterogeneity to guide future stereotactic implantation of CED catheters into the most cellular tumor regions. Patients ages 18 years or younger with a diagnosis of DIPG from 2000 to 2015 were included. Radiographic heterogeneity index (HI) of the tumor was calculated by measuring the standard deviation of signal intensity of the tumor (SD Tumor ) normalized to the genu of the corpus callosum (SD Corpus Callosum ). Four MR image types (T2-weighted, contrast-enhanced T1-weighted, FLAIR, and ADC) were analyzed at several time points both before and after radiotherapy and chemotherapy. HI values across these MR image types were compared and correlated with patient survival. MR images from 18 patients with DIPG were evaluated. The mean survival ± standard deviation was 13.8 ± 13.7 months. T2-weighted images had the highest HI (mean ± SD, 5.1 ± 2.5) followed by contrast-enhanced T1-weighted images (3.7 ± 1.5), FLAIR images (3.0 ± 1.1), and ADC maps (1.6 ± 0.4). ANOVA demonstrated that HI values were significantly higher for T2-weighted images than FLAIR (p image HI values increased, while FLAIR and ADC HI values decreased. Univariate and multivariate analyses did not reveal a relationship between HI values and patient survival (p > 0.05). For children with DIPG, T2-weighted MRI demonstrates the greatest signal intensity variance suggesting tumor heterogeneity. Within this heterogeneity, T2-weighted signal hypointensity is known to correlate with increased cellularity and thus may represent a putative target for CED catheter placement in future clinical

  13. The design and imaging characteristics of dynamic, solid-state, flat-panel x-ray image detectors for digital fluoroscopy and fluorography

    International Nuclear Information System (INIS)

    Cowen, A.R.; Davies, A.G.; Sivananthan, M.U.

    2008-01-01

    Dynamic, flat-panel, solid-state, x-ray image detectors for use in digital fluoroscopy and fluorography emerged at the turn of the millennium. This new generation of dynamic detectors utilize a thin layer of x-ray absorptive material superimposed upon an electronic active matrix array fabricated in a film of hydrogenated amorphous silicon (a-Si:H). Dynamic solid-state detectors come in two basic designs, the indirect-conversion (x-ray scintillator based) and the direct-conversion (x-ray photoconductor based). This review explains the underlying principles and enabling technologies associated with these detector designs, and evaluates their physical imaging characteristics, comparing their performance against the long established x-ray image intensifier television (TV) system. Solid-state detectors afford a number of physical imaging benefits compared with the latter. These include zero geometrical distortion and vignetting, immunity from blooming at exposure highlights and negligible contrast loss (due to internal scatter). They also exhibit a wider dynamic range and maintain higher spatial resolution when imaging over larger fields of view. The detective quantum efficiency of indirect-conversion, dynamic, solid-state detectors is superior to that of both x-ray image intensifier TV systems and direct-conversion detectors. Dynamic solid-state detectors are playing a burgeoning role in fluoroscopy-guided diagnosis and intervention, leading to the displacement of x-ray image intensifier TV-based systems. Future trends in dynamic, solid-state, digital fluoroscopy detectors are also briefly considered. These include the growth in associated three-dimensional (3D) visualization techniques and potential improvements in dynamic detector design

  14. Characteristics and performance of a micro-MOSFET: An 'imageable' dosimeter for image-guided radiotherapy

    International Nuclear Information System (INIS)

    Rowbottom, Carl G.; Jaffray, David A.

    2004-01-01

    The performance and characteristics of a miniature metal oxide semiconductor field effect transistor (micro-MOSFET) detector was investigated for its potential application to integral system tests for image-guided radiotherapy. In particular, the position of peak response to a slit of radiation was determined for the three principal axes to define the co-ordinates for the center of the active volume of the detector. This was compared to the radiographically determined center of the micro-MOSFET visible using cone-beam CT. Additionally, the angular sensitivity of the micro-MOSFET was measured. The micro-MOSFETs are clearly visible on the cone-beam CT images, and produce no artifacts. The center of the active volume of the micro-MOSFET aligned with the center of the visible micro-MOSFET on the cone-beam CT images for the x and y axes to within 0.20 mm and 0.15 mm, respectively. In z, the long axis of the detector, the peak response was found to be 0.79 mm from the tip of the visible micro-MOSFET. Repeat experiments verified that the position of the peak response of the micro-MOSFET was reproducible. The micro-MOSFET response for 360 deg. of rotation in the axial plane to the micro-MOSFET was ±2%, consistent with values quoted by the manufacturer. The location of the active volume of the micro-MOSFETs under investigation can be determined from the centroid of the visible micro-MOSFET on cone-beam CT images. The CT centroid position corresponds closely to the center of the detector response to radiation. The ability to use the cone-beam CT to locate the active volume to within 0.20 mm allows their use in an integral system test for the imaging of and dose delivery to a phantom containing an array of micro-MOSFETs. The small angular sensitivity allows the investigation of noncoplanar beams

  15. CT and MR imaging characteristics of infantile hepatic hemangioendothelioma

    International Nuclear Information System (INIS)

    Feng Shiting; Chan Tao; Ching, A.S.C.; Sun Canhui; Guo Huanyi; Fan Miao; Meng Quanfei; Li Ziping

    2010-01-01

    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.

  16. Detection of bridging veins draining into superior sagittal sinus by using susceptibility weighted imaging and three dimensional contrast enhancement MR venography

    International Nuclear Information System (INIS)

    Xia Chunhua; Chen Dan; Chen Bing; Wang Yajun; Xia Shiyong; Liu Wenli; Zhang Zhenhua; Wang Hui; Wu Lingqiao

    2011-01-01

    Objective: To use the superior sagittal sinus (SSS) as an example to identify anatomical features of the bridging veins (BVs) draining into the SSS in both susceptibility weighted imaging (SWI) and three dimensional contrast enhancement MR venography (3D-CEMRV) images. Methods: A total of 20 healthy volunteers (40 sides) were examined in this study. The venograms of each patient was obtained from SWI (40 sides out of 20 volunteers) and 3D-CE MRV (40 sides out of 20 volunteers). The data were analyzed by t test. Results: According to their draining location with respect to the SSS, bridging veins were divided into two groups. Between the anterior group and the posterior group were two segments of the SSS into which few bridging veins drained. Observed by 3D-CE MRV and SWI, the average numbers of the anterior group were 1.9±0.6 and 3.2±0.8, respectively, and the average diameters of the anterior group were (3.4±1.1) and (2.1±0.5) mm, respectively. These differences between 3D-CE MRV and SWI images were significant (t=11.23, 9.76, P<0.01). Observed by 3D-CE MRV and SWI, the average numbers of the posterior group were 3.5±1.2 and 5.9±1.1, respectively, and the average diameters of the posterior group were (3.7±0.9) and (2.9±0.7) mm, respectively. The differences between the two technique were significant as well (t=11.51, 8.47, P<0.01). Conclusion: The dural entrance of BVs into the SSS can be identified in both SWI and 3D-CE MRV images. The preoperative venogram by using 3D-CE MRV and SWI is useful to design a individual-tailored surgical approach for the preservation of BVs draining into SSS. SWI outweighs 3D-CE MRV in identifying anatomical features of the dural entrance of BVs into the SSS. (authors)

  17. Imaging characteristics of hepatocellular adenoma compared with pathologic findings

    International Nuclear Information System (INIS)

    Zhao Jing; Zhao Xinming; Ouyang Han; Huang Wenting; Zhou Chunwu

    2012-01-01

    -intense signal on the T 1 WI and hyper-intense signal on the T 2 WI with fat suppression sequences. There were 3 patients with an atypical adenoma type. One patient appeared uniform hypo-density on the non-enhanced CT and hyper-density on the hepatic arterial-dominant phase and became iso-dense on the portal venous phase. On the delay phase, it was slightly hyper-dense. Two out of the three lesions showed isointense and one hypo-intense signal on the in-phase T 1 WI, and hypo-intense, hyper-intense, and iso-intense signal on the T 2 WI with fat suppression sequences,respectively. Two patients examined on all phases of post-contrast MRI scans. The result was similar to the CT findings. Conclusion: The imaging features of hepatocellular adenoma are closely associated with pathological characteristics. (authors)

  18. Preclinical imaging characteristics and quantification of Platinum-195m SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Aalbersberg, E.A.; Wit-van der Veen, B.J. de; Vegt, E.; Vogel, Wouter V. [The Netherlands Cancer Institute (NKI-AVL), Department of Nuclear Medicine, Amsterdam (Netherlands); Zwaagstra, O.; Codee-van der Schilden, K. [Nuclear Research and Consultancy Group (NRG), Petten (Netherlands)

    2017-08-15

    In vivo biodistribution imaging of platinum-based compounds may allow better patient selection for treatment with chemo(radio)therapy. Radiolabeling with Platinum-195m ({sup 195m}Pt) allows SPECT imaging, without altering the chemical structure or biological activity of the compound. We have assessed the feasibility of {sup 195m}Pt SPECT imaging in mice, with the aim to determine the image quality and accuracy of quantification for current preclinical imaging equipment. Enriched (>96%) {sup 194}Pt was irradiated in the High Flux Reactor (HFR) in Petten, The Netherlands (NRG). A 0.05 M HCl {sup 195m}Pt-solution with a specific activity of 33 MBq/mg was obtained. Image quality was assessed for the NanoSPECT/CT (Bioscan Inc., Washington DC, USA) and U-SPECT{sup +}/CT (MILabs BV, Utrecht, the Netherlands) scanners. A radioactivity-filled rod phantom (rod diameter 0.85-1.7 mm) filled with 1 MBq {sup 195m}Pt was scanned with different acquisition durations (10-120 min). Four healthy mice were injected intravenously with 3-4 MBq {sup 195m}Pt. Mouse images were acquired with the NanoSPECT for 120 min at 0, 2, 4, or 24 h after injection. Organs were delineated to quantify {sup 195m}Pt concentrations. Immediately after scanning, the mice were sacrificed, and the platinum concentration was determined in organs using a gamma counter and graphite furnace - atomic absorption spectroscopy (GF-AAS) as reference standards. A 30-min acquisition of the phantom provided visually adequate image quality for both scanners. The smallest visible rods were 0.95 mm in diameter on the NanoSPECT and 0.85 mm in diameter on the U-SPECT{sup +}. The image quality in mice was visually adequate. Uptake was seen in the kidneys with excretion to the bladder, and in the liver, blood, and intestine. No uptake was seen in the brain. The Spearman correlation between SPECT and gamma counter was 0.92, between SPECT and GF-AAS it was 0.84, and between GF-AAS and gamma counter it was0.97 (all p < 0

  19. Imaging characteristics of noncontained migrating disc fragment and cyst

    International Nuclear Information System (INIS)

    Eerens, I.; Demaerel, P.; Haven, F.; Wilms, G.; Loon, J. van; Calenbergh, F. van

    2001-01-01

    The purpose of this article is to review less common presentations of degenerative disc disease on MR imaging. The images of eight patients were retrospectively analyzed. Six of them had transligamentous (or noncontained) disc herniations, the fragments of which were located in the posterior epidural space in three of them. One patient had a transdural disc fragment and one patient had a disc cyst. The cyst was located in the ventrolateral epidural space. On T2-weighted images, the migrated disc fragment returned a higher signal than the disc of origin in 6 of 7 patients. The disc cyst returned a signal similar to that of cerebrospinal fluid. The MR appearances of disc fragments can be puzzling, particularly if they are located in the posterior epidural space. It is important to recognize the abnormalities in order to differentiate them from less common lesions such as hematoma, abscess and neurinoma. (orig.)

  20. Imaging characteristics of noncontained migrating disc fragment and cyst

    Energy Technology Data Exchange (ETDEWEB)

    Eerens, I.; Demaerel, P.; Haven, F.; Wilms, G. [Dept. of Radiology, University Hospitals, Leuven (Belgium); Loon, J. van; Calenbergh, F. van [Dept. of Neurosurgery, University Hospitals, Leuven (Belgium)

    2001-05-01

    The purpose of this article is to review less common presentations of degenerative disc disease on MR imaging. The images of eight patients were retrospectively analyzed. Six of them had transligamentous (or noncontained) disc herniations, the fragments of which were located in the posterior epidural space in three of them. One patient had a transdural disc fragment and one patient had a disc cyst. The cyst was located in the ventrolateral epidural space. On T2-weighted images, the migrated disc fragment returned a higher signal than the disc of origin in 6 of 7 patients. The disc cyst returned a signal similar to that of cerebrospinal fluid. The MR appearances of disc fragments can be puzzling, particularly if they are located in the posterior epidural space. It is important to recognize the abnormalities in order to differentiate them from less common lesions such as hematoma, abscess and neurinoma. (orig.)

  1. Effects of characteristics of image quality in an immersive environment

    Science.gov (United States)

    Duh, Henry Been-Lirn; Lin, James J W.; Kenyon, Robert V.; Parker, Donald E.; Furness, Thomas A.

    2002-01-01

    Image quality issues such as field of view (FOV) and resolution are important for evaluating "presence" and simulator sickness (SS) in virtual environments (VEs). This research examined effects on postural stability of varying FOV, image resolution, and scene content in an immersive visual display. Two different scenes (a photograph of a fountain and a simple radial pattern) at two different resolutions were tested using six FOVs (30, 60, 90, 120, 150, and 180 deg.). Both postural stability, recorded by force plates, and subjective difficulty ratings varied as a function of FOV, scene content, and image resolution. Subjects exhibited more balance disturbance and reported more difficulty in maintaining posture in the wide-FOV, high-resolution, and natural scene conditions.

  2. Correlation characteristics of optical coherence tomography images of turbid media with statistically inhomogeneous optical parameters

    International Nuclear Information System (INIS)

    Dolin, Lev S.; Sergeeva, Ekaterina A.; Turchin, Ilya V.

    2012-01-01

    Noisy structure of optical coherence tomography (OCT) images of turbid medium contains information about spatial variations of its optical parameters. We propose analytical model of statistical characteristics of OCT signal fluctuations from turbid medium with spatially inhomogeneous coefficients of absorption and backscattering. Analytically predicted correlation characteristics of OCT signal from spatially inhomogeneous medium are in good agreement with the results of correlation analysis of OCT images of different biological tissues. The proposed model can be efficiently applied for quantitative evaluation of statistical properties of absorption and backscattering fluctuations basing on correlation characteristics of OCT images.

  3. Feature Recognition of Froth Images Based on Energy Distribution Characteristics

    Directory of Open Access Journals (Sweden)

    WU Yanpeng

    2014-09-01

    Full Text Available This paper proposes a determining algorithm for froth image features based on the amplitude spectrum energy statistics by applying Fast Fourier Transformation to analyze the energy distribution of various-sized froth. The proposed algorithm has been used to do a froth feature analysis of the froth images from the alumina flotation processing site, and the results show that the consistency rate reaches 98.1 % and the usability rate 94.2 %; with its good robustness and high efficiency, the algorithm is quite suitable for flotation processing state recognition.

  4. Imaging characteristics of pilomyxoid astrocytomas in comparison with pilocytic astrocytomas

    International Nuclear Information System (INIS)

    Lee, In Ho; Kim, Ji Hye; Suh, Yeon-Lim; Eo, Hong; Shin, Hyung Jin; Yoo, So-Young; Lee, Kyung Soo

    2011-01-01

    Purpose: Pilomyxoid astrocytoma (PMA) is a recently described astrocytic tumor that has been previously diagnosed as pilocytic astrocytoma (PA). The purpose of this study was to describe the imaging features of PMAs in comparison with PAs. Materials and methods: We retrospectively reviewed CT/MR images and medical records of 10 patients with PMA and 38 patients with PA. The mean ages of patients with PMA and PA were 10 and 15 years, respectively. Imaging features including location, composition, enhancement pattern, presence of calcification, hemorrhage, and leptomeningeal dissemination were compared in patients with two tumor types. Results: Six PMAs (60%) occurred at the suprasellar area and the cerebellum was the most common (45%) site of PA. Solid component was dominant in eight PMAs (80%) and in 19 PAs (50%). All of the PMAs containing solid mass (n = 8) included non-enhancing portion while 12/37 (32%) PAs included non-enhancing solid portion (p < 0.05). Leptomeningeal dissemination was noted in five PMAs (50%) and one PA (3%) (p < 0.05). Other imaging findings were not significantly different. Conclusion: A younger age, more frequent occurrence at the suprasellar area, mainly solid mass containing non-enhancing portion, and more frequent leptomeningeal dissemination are helpful differential features of PMAs as compared to PAs.

  5. Operational characteristics of pediatric radiology: Image display stations

    International Nuclear Information System (INIS)

    Taira, R.K.

    1987-01-01

    The display of diagnostic images is accomplished in the UCLA Pediatric Radiology Clinical Radiology Imaging System (CRIS) using 3 different types of digital viewing stations. These include a low resolution station with six 512 x 512 monitors, a high resolution station with three 1024 x 1024 monitors, and a very high resolution workstation with two 2048 x 2048 monitors. The display stations provide very basic image processing manipulations including zoom and scroll, contrast enhancement, and contrast reversal. The display stations are driven by a computer system which is dedicated for clinical use. During times when the clinical computer is unavailable (maintenance or system malfunction), the 512 x 512 workstation can be switched to operate from a research PACS system in the UCLA Image Processing Laboratory via a broadband communication network. Our initial clinical implementation involves digital viewing for pediatric radiology conferences. Presentation of inpatient cases use the six monitor 512 x 512 multiple viewing station. Later stages of the clinical implementation involve the use of higher resolution displays for the purpose of primary diagnosis from video displays

  6. Multiparametric magnetic resonance imaging characteristics of prostate tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Yue; Huang, Lixiang; Zhang, Xiaodong; Ji, Qian; Shen, Wen [Dept. of Radiology, Tianjin First Central Hospital, Tianjin (China)

    2015-08-15

    To describe the multiparametric magnetic resonance imaging (MRI) appearance of prostate tuberculosis. Six patients with prostate tuberculosis were analyzed retrospectively. The mean age of the patients was 60.5 years (range, 48-67 years). The mean prostate specific antigen concentration was 6.62 ng/mL (range, 0.54-14.57 ng/mL). All patients underwent a multiparametric MRI examination. The histopathological results were obtained from biopsies in four men and from transurethral resection of the prostate in two men after the MRI examination. Nodular (33%, 2/6 patients) and diffuse lesions (67%, 4/6 patients) were seen on MRI. The nodular lesions were featured by extremely low signal intensity (similar to that of muscle) on T2-weighted imaging (T2WI). The T2WI signal intensity of the diffuse lesions was low but higher than that of muscle, which showed high signal intensity on diffusion weighted imaging and low signal intensity on an apparent diffusion coefficient map. MR spectroscopic imaging of this type showed a normal-like spectrum. Abscesses were found in one patient with the nodular type and in one with the diffuse type. The appearance of prostate tuberculosis on MRI can be separated into multiple nodular and diffuse types. Multiparametric MRI may offer useful information for diagnosing prostate tuberculosis.

  7. Color image lossy compression based on blind evaluation and prediction of noise characteristics

    Science.gov (United States)

    Ponomarenko, Nikolay N.; Lukin, Vladimir V.; Egiazarian, Karen O.; Lepisto, Leena

    2011-03-01

    The paper deals with JPEG adaptive lossy compression of color images formed by digital cameras. Adaptation to noise characteristics and blur estimated for each given image is carried out. The dominant factor degrading image quality is determined in a blind manner. Characteristics of this dominant factor are then estimated. Finally, a scaling factor that determines quantization steps for default JPEG table is adaptively set (selected). Within this general framework, two possible strategies are considered. A first one presumes blind estimation for an image after all operations in digital image processing chain just before compressing a given raster image. A second strategy is based on prediction of noise and blur parameters from analysis of RAW image under quite general assumptions concerning characteristics parameters of transformations an image will be subject to at further processing stages. The advantages of both strategies are discussed. The first strategy provides more accurate estimation and larger benefit in image compression ratio (CR) compared to super-high quality (SHQ) mode. However, it is more complicated and requires more resources. The second strategy is simpler but less beneficial. The proposed approaches are tested for quite many real life color images acquired by digital cameras and shown to provide more than two time increase of average CR compared to SHQ mode without introducing visible distortions with respect to SHQ compressed images.

  8. Longitudinal Long-term Magnetic Resonance Imaging and Clinical Follow-up After Single-Row Arthroscopic Rotator Cuff Repair: Clinical Superiority of Structural Tendon Integrity.

    Science.gov (United States)

    Heuberer, Philipp R; Smolen, Daniel; Pauzenberger, Leo; Plachel, Fabian; Salem, Sylvia; Laky, Brenda; Kriegleder, Bernhard; Anderl, Werner

    2017-05-01

    The number of arthroscopic rotator cuff surgeries is consistently increasing. Although generally considered successful, the reported number of retears after rotator cuff repair is substantial. Short-term clinical outcomes are reported to be rarely impaired by tendon retears, whereas to our knowledge, there is no study documenting long-term clinical outcomes and tendon integrity after arthroscopic rotator cuff repair. To investigate longitudinal long-term repair integrity and clinical outcomes after arthroscopic rotator cuff reconstruction. Case series; Level of evidence, 4. Thirty patients who underwent arthroscopic rotator cuff repair with suture anchors for a full-tendon full-thickness tear of the supraspinatus or a partial-tendon full-thickness tear of the infraspinatus were included. Two and 10 years after initial arthroscopic surgery, tendon integrity was analyzed using magnetic resonance imaging (MRI). The University of California, Los Angeles (UCLA) score and Constant score as well as subjective questions regarding satisfaction with the procedure and return to normal activity were used to evaluate short- and long-term outcomes. At the early MRI follow-up, 42% of patients showed a full-thickness rerupture, while 25% had a partial rerupture, and 33% of tendons remained intact. The 10-year MRI follow-up (129 ± 11 months) showed 50% with a total rerupture, while the other half of the tendons were partially reruptured (25%) or intact (25%). The UCLA and Constant scores significantly improved from preoperatively (UCLA total: 50.6% ± 20.2%; Constant total: 44.7 ± 10.5 points) to 2 years (UCLA total: 91.4% ± 16.0% [ P rotator cuff repair showed good clinical long-term results despite a high rate of retears. Nonetheless, intact tendons provided significantly superior clinical long-term outcomes, making the improvement of tendon healing and repair integrity important goals of future research efforts.

  9. Studies of imaging characteristics for a slab of a lossy left-handed material

    International Nuclear Information System (INIS)

    Shen Linfang; He Sailing

    2003-01-01

    The characteristics of an imaging system formed by a slab of a lossy left-handed material (LHM) are studied. The transfer function of the LHM imaging system is written in an appropriate product form with each term having a clear physical interpretation. A tiny loss of the LHM may suppress the transmission of evanescent waves through the LHM slab and this is explained physically. An analytical expression for the resolution of the imaging system is derived. It is shown that it is impossible to make a subwavelength imaging by using a realistic LHM imaging system unless the LHM slab is much thinner than the wavelength

  10. Magnetic resonance characteristics and susceptibility weighted imaging of the brain in gadolinium encephalopathy.

    Science.gov (United States)

    Samardzic, Dejan; Thamburaj, Krishnamoorthy

    2015-01-01

    To report the brain imaging features on magnetic resonance imaging (MRI) in inadvertent intrathecal gadolinium administration. A 67-year-old female with gadolinium encephalopathy from inadvertent high dose intrathecal gadolinium administration during an epidural steroid injection was studied with multisequence 3T MRI. T1-weighted imaging shows pseudo-T2 appearance with diffusion of gadolinium into the brain parenchyma, olivary bodies, and membranous labyrinth. Nulling of cerebrospinal fluid (CSF) signal is absent on fluid attenuation recovery (FLAIR). Susceptibility-weighted imaging (SWI) demonstrates features similar to subarachnoid hemorrhage. CT may demonstrate a pseudo-cerebral edema pattern given the high attenuation characteristics of gadolinium. Intrathecal gadolinium demonstrates characteristic imaging features on MRI of the brain and may mimic subarachnoid hemorrhage on susceptibility-weighted imaging. Identifying high dose gadolinium within the CSF spaces on MRI is essential to avoid diagnostic and therapeutic errors. Copyright © 2013 by the American Society of Neuroimaging.

  11. Tissue characteristics in left ventricular hypertrophy using magnetic resonance imaging

    International Nuclear Information System (INIS)

    Yoshida, Shigeru; Ueno, Yuji; Arita, Mikio; Nishio, Ichiro; Masuyama, Yoshiaki

    1988-01-01

    For 15 normotensive patients with asymmetric septal hypertrophy (ASH), 10 hypertensive patients with concentric hypertrophy (CH), and five normal subjects (N), we examined changes in myocardial T 1 and T 2 values related to the cardiac cycle. The usefulness of those values in differentiating diseases with left ventricular hypertrophy was evaluated. Left ventricular (LV) short-axis spin echo images and inversion recovery images were obtained at endsystolic and diastolic cardiac phases, and T 1 and T 2 images were calculated. The regional wall thickness (WT) and T 1 and T 2 values were measured in the anterior septum, anterior wall, lateral wall, posterior wall and posterior septum. Myocardial T 1 and T 2 values were significantly decreased in systole (T 1 : 185.6±37.9 msec, T 2 : 24.4±6.3 msec, mean±SD) compared to those in diastole (T 1 : 249.2±56.7 msec, T 2 : 31.7±9.4 msec). In both the ASH and CH groups, significant correlations were observed between diastolic T 1 values and WT (ASH: r = 0.80, p 2 values and WT (ASH: r = 0.58, p 1 values in the ASH group (343.4±40.5 msec) were significantly higher than those of the CH group (247.3±21.4 msec), although the mean wall thickness values were similar in both groups. The T 1 /WT and T 2 /WT were significantly lower in the CH group than those in the ASH and N groups. In conclusion, myocardial T 1 and T 2 values were related not only to the cardiac cycle, but to wall thickness and to types of hypertrophy. The T 1 and T 2 values may be useful for distinguishing hypertrophic cardiomyopathy from hypertrophy due to hypertension. (author)

  12. Magnetic Resonance Imaging Characteristics of Ovarian Clear Cell Carcinoma.

    Directory of Open Access Journals (Sweden)

    Wei Wang

    Full Text Available To probe the magnetic resonance imaging (MRI features of ovarian clear cell carcinoma (OCCC.This study retrospectively collected MRI data for 21 pathology-confirmed OCCCs from 19 female patients. The MRI findings were analyzed to determine the tumor size, shape/edge, shape and number of protrusions within the cyst, cystic or necrotic components, signal intensity (SI and enhancement features.The age of the 19 patients ranged from 28 to 63 years (mean age: 53 years. Unilateral tumors were found in 17 patients (17/19, 89%; the average size of all tumors was 10.8 cm. The tumors on MRI were classified into two categories: (a "cystic adnexal mass with solid protrusions" in 12 (57% and (b "solid adnexal mass with cystic areas or necrosis" in 9 (43%. For group a, high to very high SI was observed for most tumors (10/12, 83% on T1-weighted images (T1WIs, and very high SI was observed on T2-weighted images (T2WIs for all 12 tumors. Most solid protrusions were irregular and few in number and exhibited heterogeneous intermediate SI on T1WIs and T2WIs and prolonged enhanced SI in the contrast study. All 9 OCCCs in group b were predominantly solid masses with unequally sized necrotic or cystic areas in which some cysts were located at the periphery of the tumor (4/9, 44%. The solid components in all 9 tumors showed iso- or slightly high SI on T1WIs, heterogeneous iso-high SI on T2WIs and heterogeneous prolonged enhancement. According to FIGO classification, 14 tumors (14/19, 74% were stages I-II, and 5 (5/19, 26% were stages III-IV.On MRI, OCCCs present as large unilateral multilocular or unilocular cystic masses with irregular intermediate SI solid protrusions or predominantly solid masses with cysts or necrosis at an early FIGO stage.

  13. Imaging and clinical characteristics of sporadic Creutzfeldt-Jakob disease

    Directory of Open Access Journals (Sweden)

    HAN Shun-chang

    2013-04-01

    Full Text Available Five patients with sporadic Creutzfeldt-Jakob disease (sCJD presented rapidly progressive dementia which were subacute onset from 1 to 4 months. Among these cases, periodic synchronous discharge (PSD of electroencephalography (EEG was seen in 2 patients. Besides, 4 patients obtained positive results in cerebrospinal fluid (CSF analysis for 14-3-3 protein. The cranial MRI examination showed symmetrical or asymmetrical colored-ribbon-shaped high signals in cerebral cortex or basal ganglia by diffusion weighted imaging (DWI, suggesting that DWI had high sensitivity and specificity for the diagnosis of sCJD as a preferred method in the clinical examination of sCJD.

  14. Isolated abscess in superior rectus muscle in a child

    Directory of Open Access Journals (Sweden)

    Sushank Ashok Bhalerao

    2015-01-01

    Full Text Available Pyomyositis is a primary bacterial infection of striated muscles nearly always caused by Staphylococcus aureus. Development of the intramuscular abscess involving the extra-ocular muscles (EOMs remains an extremely rare process. We herein present a case of isolated EOM pyomyositis involving superior rectus muscle in a 2-year male child who was referred with complaints of swelling in left eye (LE and inability to open LE since last 1-month. Orbital computed tomography (CT scan showed a well-defined, hypo-dense, peripheral rim-enhancing lesion in relation to left superior rectus muscle suggestive of left superior rectus abscess. The abscess was drained through skin approach. We concluded that pyomyositis of EOM should be considered in any patient presenting with acute onset of orbital inflammation and characteristic CT or magnetic resonance imaging features. Management consists of incision and drainage coupled with antibiotic therapy.

  15. Characteristics of calcaneal bone infarction: an MR imaging investigation

    Energy Technology Data Exchange (ETDEWEB)

    Abrahim-Zadeh, R.; Klein, R.M.; Leslie, D.; Norman, A. [Department of Radiology, New York Medical College, Macy Pavillion, Valhalla, NY 10595 (United States)

    1998-06-01

    Objective. Bone infarction (BI) of the calcaneus is an uncommon entity which has received little mention in the recent literature. In this paper, we review the MR images of six calcanei with BI, which demonstrate a pattern of presentation that may explain the etiology of BI at this unusual location. Design. A retrospective review was performed of the transcribed reports of the foot or ankle MR examinations at our institution. MR images of examinations with any marrow signal abnormality were reviewed for presence of BI and its distribution. Patients. Based on MRI criteria, four patients had calcaneal BI (none biopsy proven); they ranged in age from 37 to 51 years old. Two patients were diagnosed with systemic lupus erythematosus, one with fibrositis, and another with polymyositis. All were treated with corticosteroids. Results. Six calcanei (in four patients) contained a region of calcaneal BI. In five of the six, the lesions were entirely or predominantly located in the posterior half of the calcaneus. Conclusion. Two theories are proposed which may explain why BI predominantly occurs in the posterior half of the calcaneus. First, the convergence of the recurrent intraosseous calcaneal vessels may occasionally produce the equivalent of a single dominant vessel that is more prone to vascular accidents. Secondly, the region between the recurrent and the epiphyseal vessels may act as a watershed zone, increasing its susceptibility to ischemia. (orig.) With 4 figs., 1 tab., 8 refs.

  16. Language Development and Brain Magnetic Resonance Imaging Characteristics in Preschool Children with Cerebral Palsy

    Science.gov (United States)

    Choi, Ja Young; Choi, Yoon Seong; Park, Eun Sook

    2017-01-01

    Purpose: The purpose of this study was to investigate characteristics of language development in relation to brain magnetic resonance imaging (MRI) characteristics and the other contributing factors to language development in children with cerebral palsy (CP). Method: The study included 172 children with CP who underwent brain MRI and language…

  17. Pictorial Superiority Effect

    Science.gov (United States)

    Nelson, Douglas L.; And Others

    1976-01-01

    Pictures generally show superior recognition relative to their verbal labels. This experiment was designed to link this pictorial superiority effect to sensory or meaning codes associated with the two types of symbols. (Editor)

  18. Imaging characteristics in legally founded cases of assaultive child abuse

    International Nuclear Information System (INIS)

    Lin-Dyken, D.; Smith, W.L.; Alexander, R.

    1990-01-01

    This paper reports on this study performed to document the imaging findings associated with assaultive child abuse as confirmed by an independent criterion. At least one of the authors acted as a consultant in 105 alleged cases of child abuse owing to physical assault between 1987 and 1989. Seventy-six cases were founded by the Department of Human Services. 57/76 of founded cases had fractures. Most commonly only one fracture was noted (32 cases), but up to seven fractures were present in a patient. The tibia was the most commonly fractured bone (23 cases) followed in frequency by the femur (22), skull (15), and humerus (14). Multiple rib fractures were seen in 10 cases

  19. Fourier Analysis of Single-Shot Dual-Energy X-ray Imaging Characteristics

    International Nuclear Information System (INIS)

    Kim, Jun Woo; Kim, Dong Woon; Kim, Ho Kyung

    2016-01-01

    The sandwich detector was realized by stacking two scintillator-based flat-panel detectors (FPDs) between which an intermediate copper (Cu) filter layer was placed to further enhance spectral energy separation. As a result, the proper selection of filter material and its thickness could be a trade-off between the extent of energy separation (hence, DE image quality) and image noise due to reduction in the number of x-ray quanta reaching the rear FPD. Although the conventional kVp-switching dual-shot method showed better image qualities than the single-shot method because of larger spectral energy separation, the motion-artifact-free DE image with reasonably good image quality was a potential prospect of the single-shot method. For the reliable and better use of the sandwich detector for specific imaging applications, the sandwich detector should be optimally designed with a proper selection of scintillator material and thickness in each detector layer (i.e. the front and rear detectors), and aforementioned intermediate filter material and thickness. It is noted that glue is used to adhere the fragile photodiode array onto the ceramic substrate and these glue patterns are apparent in the rear and DE images. The glue pattern in the rear image comes from the front FPD. Unlike the conventional ESF as shown in Fig. 3(a), the ESF obtained from the subtracted image showed an enhancement as shown in Fig. 3(b). Consequently, the MTF obtained from the subtraction ESF showed a bandpass filter characteristic, as shown in Fig. 3(c), unlike the conventional low-pass filter characteristic (i.e., monotonic decrease of MTF value with increasing the spatial frequency). This MTF characteristic is due to the subtraction of two images with different spatial resolving powers (i.e., different thicknesses of phosphors between the front and rear detectors) as can be seen in unsharp masking digital image processing, which subtracts Gaussian-blurred image from the original image

  20. Fourier Analysis of Single-Shot Dual-Energy X-ray Imaging Characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jun Woo; Kim, Dong Woon; Kim, Ho Kyung [Pusan National University, Busan (Korea, Republic of)

    2016-05-15

    The sandwich detector was realized by stacking two scintillator-based flat-panel detectors (FPDs) between which an intermediate copper (Cu) filter layer was placed to further enhance spectral energy separation. As a result, the proper selection of filter material and its thickness could be a trade-off between the extent of energy separation (hence, DE image quality) and image noise due to reduction in the number of x-ray quanta reaching the rear FPD. Although the conventional kVp-switching dual-shot method showed better image qualities than the single-shot method because of larger spectral energy separation, the motion-artifact-free DE image with reasonably good image quality was a potential prospect of the single-shot method. For the reliable and better use of the sandwich detector for specific imaging applications, the sandwich detector should be optimally designed with a proper selection of scintillator material and thickness in each detector layer (i.e. the front and rear detectors), and aforementioned intermediate filter material and thickness. It is noted that glue is used to adhere the fragile photodiode array onto the ceramic substrate and these glue patterns are apparent in the rear and DE images. The glue pattern in the rear image comes from the front FPD. Unlike the conventional ESF as shown in Fig. 3(a), the ESF obtained from the subtracted image showed an enhancement as shown in Fig. 3(b). Consequently, the MTF obtained from the subtraction ESF showed a bandpass filter characteristic, as shown in Fig. 3(c), unlike the conventional low-pass filter characteristic (i.e., monotonic decrease of MTF value with increasing the spatial frequency). This MTF characteristic is due to the subtraction of two images with different spatial resolving powers (i.e., different thicknesses of phosphors between the front and rear detectors) as can be seen in unsharp masking digital image processing, which subtracts Gaussian-blurred image from the original image.

  1. New neutron imaging using pulsed sources. Characteristics of a pulsed neutron source and principle of pulsed neutron imaging

    International Nuclear Information System (INIS)

    Kiyanagi, Yoshiaki

    2012-01-01

    Neutron beam is one of important tools to obtain the transmission image of an object. Until now, steady state neutron sources such as reactors are mainly used for this imaging purpose. Recently, it has been demonstrated that pulsed neutron imaging based on accelerator neutron sources can provide a real-space distribution of physical information of materials such as crystallographic structure, element, temperature, hydrogen bound state, magnetic field and so on, by analyzing wavelength dependent transmission spectrum, which information cannot be observed or difficult to obtain with a traditional imaging method using steady state neutrons. Here, characteristics of the pulsed neutron source and principle of the pulsed neutron imaging are explained as a basic concept of the new method. (author)

  2. Imaging characteristics of supratentorial ependymomas: Study on a large single institutional cohort with histopathological correlation.

    Science.gov (United States)

    Mangalore, Sandhya; Aryan, Saritha; Prasad, Chandrajit; Santosh, Vani

    2015-01-01

    Supratentorial ependymoma (STE) is a tumor whose unique clinical and imaging characteristics have not been studied. Histopathologically, they resemble ependymoma elsewhere. We retrospectively reviewed the imaging findings with clinicopathological correlation in a large number of patients with STE to identify these characteristics. Computed tomography (CT) magnetic resonance images (MRI), pathology reports, and clinical information from 41 patients with pathology-confirmed STE from a single institution were retrospectively reviewed. CT and MRI findings including location, size, signal intensity, hemorrhage, and enhancement pattern were tabulated and described separately in intraventricular and intraparenchymal forms. STE was more common in pediatric age group and intraparenchymal was more common than intraventricular form. The most common presentation was features of raised intracranial tension. There were equal numbers of Grade II and Grade III tumors. The imaging characteristics in adult and pediatric age group were similar. The tumor was large and had both solid and cystic components. Advanced imaging such as diffusion, perfusion, and spectroscopy were suggestive of high-grade tumor. Only differentiating factor between Grade II and Grade III was the presence of calcification. 1234 rule and periwinkle sign which we have described in this article may help characterize this tumor on imaging. This series expands the clinical and imaging spectrum of STE and identifies characteristics that should suggest consideration of this uncommon diagnosis.

  3. [Influence of human body target's spectral characteristics on visual range of low light level image intensifiers].

    Science.gov (United States)

    Zhang, Jun-Ju; Yang, Wen-Bin; Xu, Hui; Liu, Lei; Tao, Yuan-Yaun

    2013-11-01

    To study the effect of different human target's spectral reflective characteristic on low light level (LLL) image intensifier's distance, based on the spectral characteristics of the night-sky radiation and the spectral reflective coefficients of common clothes, we established a equation of human body target's spectral reflective distribution, and analyzed the spectral reflective characteristics of different human targets wearing the clothes of different color and different material, and from the actual detection equation of LLL image intensifier distance, discussed the detection capability of LLL image intensifier for different human target. The study shows that the effect of different human target's spectral reflective characteristic on LLL image intensifier distance is mainly reflected in the average reflectivity rho(-) and the initial contrast of the target and the background C0. Reflective coefficient and spectral reflection intensity of cotton clothes are higher than polyester clothes, and detection capability of LLL image intensifier is stronger for the human target wearing cotton clothes. Experimental results show that the LLL image intensifiers have longer visual ranges for targets who wear cotton clothes than targets who wear same color but polyester clothes, and have longer visual ranges for targets who wear light-colored clothes than targets who wear dark-colored clothes. And in the full moon illumination conditions, LLL image intensifiers are more sensitive to the clothes' material.

  4. Image quality characteristics of a novel colour scanning digital ophthalmoscope (SDO) compared with fundus photography.

    Science.gov (United States)

    Strauss, Rupert W; Krieglstein, Tina R; Priglinger, Siegfried G; Reis, Werner; Ulbig, Michael W; Kampik, Anselm; Neubauer, Aljoscha S

    2007-11-01

    To establish a set of quality parameters for grading image quality and apply those to evaluate the fundus image quality obtained by a new scanning digital ophthalmoscope (SDO) compared with standard slide photography. On visual analogue scales a total of eight image characteristics were defined: overall quality, contrast, colour brilliance, focus (sharpness), resolution and details, noise, artefacts and validity of clinical assessment. Grading was repeated after 4 months to assess repeatability. Fundus images of 23 patients imaged digitally by SDO and by Zeiss 450FF fundus camera using Kodak film were graded side-by-side by three graders. Lens opacity was quantified with the Interzeag Lens Opacity Meter 701. For all of the eight scales of image quality, good repeatability within the graders (mean Kendall's W 0.69) was obtained after 4 months. Inter-grader agreement ranged between 0.31 and 0.66. Despite the SDO's limited nominal image resolution of 720 x 576 pixels, the Zeiss FF 450 camera performed better in only two of the subscales - noise (p = 0.001) and artefacts (p = 0.01). Lens opacities significantly influenced only the two subscales 'resolution' and 'details', which deteriorated with increasing media opacities for both imaging systems. Distinct scales to grade image characteristics of different origin were developed and validated. Overall SDO digital imaging was found to provide fundus pictures of a similarly high level of quality as expert photography on slides.

  5. Imaging characteristics of Zernike and annular polynomial aberrations.

    Science.gov (United States)

    Mahajan, Virendra N; Díaz, José Antonio

    2013-04-01

    The general equations for the point-spread function (PSF) and optical transfer function (OTF) are given for any pupil shape, and they are applied to optical imaging systems with circular and annular pupils. The symmetry properties of the PSF, the real and imaginary parts of the OTF, and the modulation transfer function (MTF) of a system with a circular pupil aberrated by a Zernike circle polynomial aberration are derived. The interferograms and PSFs are illustrated for some typical polynomial aberrations with a sigma value of one wave, and 3D PSFs and MTFs are shown for 0.1 wave. The Strehl ratio is also calculated for polynomial aberrations with a sigma value of 0.1 wave, and shown to be well estimated from the sigma value. The numerical results are compared with the corresponding results in the literature. Because of the same angular dependence of the corresponding annular and circle polynomial aberrations, the symmetry properties of systems with annular pupils aberrated by an annular polynomial aberration are the same as those for a circular pupil aberrated by a corresponding circle polynomial aberration. They are also illustrated with numerical examples.

  6. Image acquisitions, processing and analysis in the process of obtaining characteristics of horse navicular bone

    Science.gov (United States)

    Zaborowicz, M.; Włodarek, J.; Przybylak, A.; Przybył, K.; Wojcieszak, D.; Czekała, W.; Ludwiczak, A.; Boniecki, P.; Koszela, K.; Przybył, J.; Skwarcz, J.

    2015-07-01

    The aim of this study was investigate the possibility of using methods of computer image analysis for the assessment and classification of morphological variability and the state of health of horse navicular bone. Assumption was that the classification based on information contained in the graphical form two-dimensional digital images of navicular bone and information of horse health. The first step in the research was define the classes of analyzed bones, and then using methods of computer image analysis for obtaining characteristics from these images. This characteristics were correlated with data concerning the animal, such as: side of hooves, number of navicular syndrome (scale 0-3), type, sex, age, weight, information about lace, information about heel. This paper shows the introduction to the study of use the neural image analysis in the diagnosis of navicular bone syndrome. Prepared method can provide an introduction to the study of non-invasive way to assess the condition of the horse navicular bone.

  7. ANALYSIS OF SPECTRAL CHARACTERISTICS AMONG DIFFERENT SENSORS BY USE OF SIMULATED RS IMAGES

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This research, by use of RS image-simulating method, simulated apparent reflectance images at sensor level and ground-reflectance images of SPOT-HRV,CBERS-CCD,Landsat-TM and NOAA14-AVHRR' s corresponding bands. These images were used to analyze sensor's differences caused by spectral sensitivity and atmospheric impacts. The differences were analyzed on Normalized Difference Vegetation Index(NDVI). The results showed that the differences of sensors' spectral characteristics cause changes of their NDVI and reflectance. When multiple sensors' data are applied to digital analysis, the error should be taken into account. Atmospheric effect makes NDVI smaller, and atn~pheric correction has the tendency of increasing NDVI values. The reflectance and their NDVIs of different sensors can be used to analyze the differences among sensor' s features. The spectral analysis method based on RS simulated images can provide a new way to design the spectral characteristics of new sensors.

  8. Image quality characteristics for virtual monoenergetic images using dual-layer spectral detector CT: Comparison with conventional tube-voltage images.

    Science.gov (United States)

    Sakabe, Daisuke; Funama, Yoshinori; Taguchi, Katsuyuki; Nakaura, Takeshi; Utsunomiya, Daisuke; Oda, Seitaro; Kidoh, Masafumi; Nagayama, Yasunori; Yamashita, Yasuyuki

    2018-05-01

    To investigate the image quality characteristics for virtual monoenergetic images compared with conventional tube-voltage image with dual-layer spectral CT (DLCT). Helical scans were performed using a first-generation DLCT scanner, two different sizes of acrylic cylindrical phantoms, and a Catphan phantom. Three different iodine concentrations were inserted into the phantom center. The single-tube voltage for obtaining virtual monoenergetic images was set to 120 or 140 kVp. Conventional 120- and 140-kVp images and virtual monoenergetic images (40-200-keV images) were reconstructed from slice thicknesses of 1.0 mm. The CT number and image noise were measured for each iodine concentration and water on the 120-kVp images and virtual monoenergetic images. The noise power spectrum (NPS) was also calculated. The iodine CT numbers for the iodinated enhancing materials were similar regardless of phantom size and acquisition method. Compared with the iodine CT numbers of the conventional 120-kVp images, those for the monoenergetic 40-, 50-, and 60-keV images increased by approximately 3.0-, 1.9-, and 1.3-fold, respectively. The image noise values for each virtual monoenergetic image were similar (for example, 24.6 HU at 40 keV and 23.3 HU at 200 keV obtained at 120 kVp and 30-cm phantom size). The NPS curves of the 70-keV and 120-kVp images for a 1.0-mm slice thickness over the entire frequency range were similar. Virtual monoenergetic images represent stable image noise over the entire energy spectrum and improved the contrast-to-noise ratio than conventional tube voltage using the dual-layer spectral detector CT. Copyright © 2018 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  9. Immunochemical faecal occult blood tests have superior stability and analytical performance characteristics over guaiac-based tests in a controlled in vitro study.

    LENUS (Irish Health Repository)

    Lee, Chun Seng

    2011-06-01

    The aims of this study were (1) to determine the measurement accuracy of a widely used guaiac faecal occult blood test (gFOBT) compared with an immunochemical faecal occult blood test (iFOBT) during in vitro studies, including their analytical stability over time at ambient temperature and at 4°C; and (2) to compare analytical imprecision and other characteristics between two commercially available iFOBT methods.

  10. Characteristic performance evaluation of a photon counting Si strip detector for low dose spectral breast CT imaging

    Science.gov (United States)

    Cho, Hyo-Min; Barber, William C.; Ding, Huanjun; Iwanczyk, Jan S.; Molloi, Sabee

    2014-01-01

    measured with the 22 keV photons from a 109Cd source was less than 9%. A reduction of image noise was shown in all the spatial frequencies in 1D NPS as a result of the elimination of the electronic noise. The spatial resolution was measured just above 5 line pairs per mm (lp/mm) where 10% of MTF corresponded to 5.4 mm−1. The 2D NPS and NEQ shows a low noise floor and a linear dependence on dose. The reconstruction filter choice affected both of the MTF and NPS results, but had a weak effect on the NEQ. Conclusions: The prototype energy resolved photon counting Si strip detector can offer superior imaging performance for dedicated breast CT as compared to a conventional energy-integrating detector due to its high output count rate, high spatial and energy resolution, and low noise characteristics, which are essential characteristics for spectral breast CT imaging. PMID:25186390

  11. TU-A-201-01: Introduction to In-Room Imaging System Characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Chang, J. [Northwell Health (United States)

    2016-06-15

    Recent years have seen a widespread proliferation of available in-room image guidance systems for radiation therapy target localization with many centers having multiple in-room options. In this session, available imaging systems for in-room IGRT will be reviewed highlighting the main differences in workflow efficiency, targeting accuracy and image quality as it relates to target visualization. Decision-making strategies for integrating these tools into clinical image guidance protocols that are tailored to specific disease sites like H&N, lung, pelvis, and spine SBRT will be discussed. Learning Objectives: Major system characteristics of a wide range of available in-room imaging systems for IGRT. Advantages / disadvantages of different systems for site-specific IGRT considerations. Concepts of targeting accuracy and time efficiency in designing clinical imaging protocols.

  12. Edema in the retropharyngeal space associated with head and neck tumors: CT imaging characteristics

    International Nuclear Information System (INIS)

    Kurihara, Noriko; Nakamura, Mamoru; Tsuda, Masashi; Saito, Haruo; Takahashi, Shoki; Higano, Shuichi

    2005-01-01

    To determine computed tomographic (CT) imaging characteristics of retropharygeal edema, we reviewed CT images in 18 patients with head and neck tumors. Retropharyngeal edema spread craniocaudally between soft palate and upper half of thyroid cartilage in all patients. No edema fluid extended above soft palate and below thyroid cartilage. Horizontally, it spread symmetrically in ten and asymmetrically in eight patients. Predominance in asymmetrical retropharyngeal edema was found on the same side as that of unilateral predominance both in lymph nodes enlargement and jugular vein stenosis/occlusion. All patients had edema also in other cervical spaces. Edema of retropharyngeal and other spaces fluctuated synchronously. In 14 patients, as primary lesion and/or cervical lymph nodes regressed, retropharyngeal edema disappeared or decreased. Retropharyngeal edema had some imaging characteristics. With knowledge of that, we could avoid diagnostic confusion when evaluating head and neck CT images. (orig.)

  13. Some imaging characteristics of the dynamic spatial reconstructor X-ray scanner system

    International Nuclear Information System (INIS)

    Behrenbeck, T.; Sinak, L.J.; Robb, R.A.; Kinsey, J.H.; Ritman, E.L.

    1984-01-01

    In late 1979, the Dynamic Spatial Reconstructor (DSR), a multiple X-ray source, stop action, volume scanning imaging device was installed. At present, the operational characteristics and biomedical utility of the DSR are being evaluated. This research project involves scanning experimental animals and carefully selected patients with cardiovascular and pulmonary pathology. The DSR scanner utilizes a computerized transaxial tomography principle to generate images of transverse slices of the body. (Auth.)

  14. Characteristics of compressed natural gas jet and jet-wall impingement using the Schlieren imaging technique

    International Nuclear Information System (INIS)

    Ismael, M A; Heikal, M R; Baharom, M B

    2013-01-01

    An experimental study was performed to investigate the compressed natural gas jet characteristics and jet-wall impingement using the Schlieren imaging technique and image processing. An injector driver was used to drive the natural gas injector and synchronized with camera triggering. A constant-volume optical chamber was designed to facilitate maximum optical access for the study of the jet macroscopic characteristics and jet-wall impingement at different injection pressures and injectors-wall distances. Measurement of the jet tip penetration and cone angle at different conditions are presented in this paper together with temporal presentation of the jet radial travel along the wall.

  15. An Imaging System for Automated Characteristic Length Measurement of Debrisat Fragments

    Science.gov (United States)

    Moraguez, Mathew; Patankar, Kunal; Fitz-Coy, Norman; Liou, J.-C.; Sorge, Marlon; Cowardin, Heather; Opiela, John; Krisko, Paula H.

    2015-01-01

    The debris fragments generated by DebriSat's hypervelocity impact test are currently being processed and characterized through an effort of NASA and USAF. The debris characteristics will be used to update satellite breakup models. In particular, the physical dimensions of the debris fragments must be measured to provide characteristic lengths for use in these models. Calipers and commercial 3D scanners were considered as measurement options, but an automated imaging system was ultimately developed to measure debris fragments. By automating the entire process, the measurement results are made repeatable and the human factor associated with calipers and 3D scanning is eliminated. Unlike using calipers to measure, the imaging system obtains non-contact measurements to avoid damaging delicate fragments. Furthermore, this fully automated measurement system minimizes fragment handling, which reduces the potential for fragment damage during the characterization process. In addition, the imaging system reduces the time required to determine the characteristic length of the debris fragment. In this way, the imaging system can measure the tens of thousands of DebriSat fragments at a rate of about six minutes per fragment, compared to hours per fragment in NASA's current 3D scanning measurement approach. The imaging system utilizes a space carving algorithm to generate a 3D point cloud of the article being measured and a custom developed algorithm then extracts the characteristic length from the point cloud. This paper describes the measurement process, results, challenges, and future work of the imaging system used for automated characteristic length measurement of DebriSat fragments.

  16. Applications and characteristics of imaging plates as detector in neutron radiography at SINQ

    CERN Document Server

    Kolbe, H; Gunia, W; Körner, S

    1999-01-01

    Imaging plate technique is a commonly accepted method in many fields as in medicine, biology and physics for detection of the distribution of beta- and gamma-radiation or X-rays on large areas. Recently a new type of imaging plate sensitive to neutrons has been developed. The storage layer is doped with gadolinium, which, after absorption of neutrons, produces radiation detectable by the same sensitive crystals used in conventional imaging plates. At the spallation neutron source, SINQ, at the Paul Scherrer Institut (CH) some of the characteristics of the neutron radiography station in combination with the imaging plate technique were investigated. The intensity distribution of the source was measured to check the accuracy for quantification of the image data. Also, the reproducibility of results obtained by this detection system was stated. For a test object, the high selectivity for different neutron absorption is demonstrated at details with low contrast. The obtainable spatial resolution was determined re...

  17. The spectral combination characteristic of grating and the bi-grating diffraction imaging effect

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This paper reports on a new property of grating, namely spectral combination, and on bi-grating diffraction imaging that is based on spectral combination. The spectral combination characteristic of a grating is the capability of combining multiple light beams of different wavelengths incident from specific angles into a single beam. The bi-grating diffraction imaging is the formation of the image of an object with two gratings: the first grating disperses the multi-color light beams from the object and the second combines the dispersed light beams to form the image. We gave the conditions necessary for obtaining the spectral combination. We also presented the equations that relate the two gratings’ spatial frequencies, diffraction orders and positions necessary for obtaining the bi-grating diffraction imaging.

  18. Study on fractal characteristics of remote sensing image in the typical volcanic uranium metallogenic areas

    International Nuclear Information System (INIS)

    Pan Wei; Ni Guoqiang; Li Hanbo

    2010-01-01

    Computing Methods of fractal dimension and multifractal spectrum about the remote sensing image are briefly introduced. The fractal method is used to study the characteristics of remote sensing images in Xiangshan and Yuhuashan volcanic uranium metallogenic areas in southern China. The research results indicate that the Xiangshan basin in which lots of volcanic uranium deposits occur,is of bigger fractal dimension based on remote sensing image texture than that of the Yuhuashan basin in which two uranium ore occurrences exist, and the multifractal spectrum in the Xiangshan basin obviously leans to less singularity index than in the Yuhuashan basin. The relation of the fractal dimension and multifractal singularity of remote sensing image to uranium metallogeny are discussed. The fractal dimension and multifractal singularity index of remote sensing image may be used to predict the volcanic uranium metallogenic areas. (authors)

  19. Imaging characteristics of focal splenic and hepatic lesions in type 1 Gaucher disease.

    Science.gov (United States)

    Regenboog, Martine; Bohte, Anneloes E; Somers, Inne; van Delden, Otto M; Maas, Mario; Hollak, Carla E M

    2016-09-01

    In Gaucher disease (GD) imaging of liver and spleen is part of routine follow-up of GD patients. Focal lesions in both liver and spleen are frequently reported at radiological examinations. These lesions often represent benign accumulations of Gaucher cells, so-called "gaucheroma", but malignancies, especially hepatocellular carcinoma, are more frequently found in GD as well. We report the imaging characteristics of all focal lesions in liver and spleen in the Dutch GD cohort. Of the 95 GD1 patients, 40% had focal splenic and/or hepatic lesions, associated with more severe GD. Lesions identified as gaucheroma have variable imaging characteristics: hyper- to hypointense on MRI, hyper- or hypoechoic on US and hypodense on computed tomography (CT). Hepatic lesions were classified as simple cysts or haemangioma based upon imaging characteristics. Focal nodular hyperplasia (FNH), gaucheroma and hepatocellular carcinoma (HCC) could not be distinguished by conventional US, CT or MRI. Growth of these lesions and/or characteristics of HCC on dynamic CT or MRI and pathology was used to identify or rule out HCC. We propose a decision-making algorithm including the use of growth and dynamic CT- or MRI-scanning to characterize lesions. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Predicting Electron Population Characteristics in 2-D Using Multispectral Ground-Based Imaging

    Science.gov (United States)

    Grubbs, Guy; Michell, Robert; Samara, Marilia; Hampton, Donald; Jahn, Jorg-Micha

    2018-01-01

    Ground-based imaging and in situ sounding rocket data are compared to electron transport modeling for an active inverted-V type auroral event. The Ground-to-Rocket Electrodynamics-Electrons Correlative Experiment (GREECE) mission successfully launched from Poker Flat, Alaska, on 3 March 2014 at 11:09:50 UT and reached an apogee of approximately 335 km over the aurora. Multiple ground-based electron-multiplying charge-coupled device (EMCCD) imagers were positioned at Venetie, Alaska, and aimed toward magnetic zenith. The imagers observed the intensity of different auroral emission lines (427.8, 557.7, and 844.6 nm) at the magnetic foot point of the rocket payload. Emission line intensity data are correlated with electron characteristics measured by the GREECE onboard electron spectrometer. A modified version of the GLobal airglOW (GLOW) model is used to estimate precipitating electron characteristics based on optical emissions. GLOW predicted the electron population characteristics with 20% error given the observed spectral intensities within 10° of magnetic zenith. Predictions are within 30% of the actual values within 20° of magnetic zenith for inverted-V-type aurora. Therefore, it is argued that this technique can be used, at least in certain types of aurora, such as the inverted-V type presented here, to derive 2-D maps of electron characteristics. These can then be used to further derive 2-D maps of ionospheric parameters as a function of time, based solely on multispectral optical imaging data.

  1. Multiparametric magnetic resonance imaging characteristics of normal, benign and malignant conditions in the prostate

    Energy Technology Data Exchange (ETDEWEB)

    Visschere, Pieter J.L. de; Pattyn, Eva; Villeirs, Geert M. [Ghent University Hospital, Department of Radiology, Ghent (Belgium); Vral, Anne [Ghent University Hospital, Department of Basic Medical Sciences, Ghent (Belgium); Perletti, Gianpaolo [Ghent University Hospital, Department of Basic Medical Sciences, Ghent (Belgium); University of Insubria, Clinical Pharmacology, Medical and Surgical Sciences Section, Department of Biotechnology and Life Sciences, Varese (Italy); Praet, Marleen [Ghent University Hospital, Department of Pathology, Ghent (Belgium); Magri, Vittorio [Instituti Clinici di Perfezionamento, Urology Clinic, Milano (Italy)

    2017-05-15

    To identify the multiparametric magnetic resonance imaging (mpMRI) characteristics of normal, benign and malignant conditions in the prostate. Fifty-six histopathological whole-mount radical prostatectomy specimens from ten randomly selected patients with prostate cancer (PC) were matched with corresponding transverse mpMRI slices. The mpMRI was performed prior to biopsy and consisted of T2-weighted imaging (T2-WI), diffusion-weighted imaging (DWI), dynamic contrast-enhanced imaging (DCE) and magnetic resonance spectroscopic imaging (MRSI). In each prostate specimen, a wide range of histopathological conditions were observed. They showed consistent but overlapping characteristics on mpMRI. Normal glands in the transition zone showed lower signal intensity (SI) on T2-WI, lower ADC values and lower citrate peaks on MRSI as compared to the peripheral zone (PZ) due to sparser glandular elements and more prominent collagenous fibres. In the PZ, normal glands were iso-intense on T2-WI, while high SI areas represented cystic atrophy. Mimickers of well-differentiated PC on mpMRI were inflammation, adenosis, HG-PIN and post-atrophic hyperplasia. Each prostate is a unique mix of normal, benign and/or malignant areas that vary in extent and distribution resulting in very heterogeneous characteristics on mpMRI. Understanding the main concepts of this mpMRI-histopathological correlation may increase the diagnostic confidence in reporting mpMRI. (orig.)

  2. Relationships among muscle dysmorphia characteristics, body image quality of life, and coping in males.

    Science.gov (United States)

    Tod, D; Edwards, C

    2015-09-01

    The purpose of this study was to examine relationships among bodybuilding dependence, muscle satisfaction, body image-related quality of life and body image-related coping strategies, and test the hypothesis that muscle dysmorphia characteristics may predict quality of life via coping strategies. Participants (294 males, Mage=20.5 years, SD=3.1) participated in a cross-sectional survey. Participants completed questionnaires assessing muscle satisfaction, bodybuilding dependence, body image-related quality of life and body image-related coping. Quality of life was correlated positively with muscle satisfaction and bodybuilding dependence but negatively with body image coping (P<0.05). Body image coping was correlated positively with bodybuilding dependence and negatively with muscle satisfaction (P<0.05). Mediation analysis found that bodybuilding dependence and muscle satisfaction predicted quality of life both directly and indirectly via body image coping strategies (as evidenced by the bias corrected and accelerated bootstrapped confidence intervals). These results provide preliminary evidence regarding the ways that muscularity concerns might influence body image-related quality of life. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  3. 99mTc-HYNIC-TOC scintigraphy is superior to 131I-MIBG imaging in the evaluation of extraadrenal pheochromocytoma.

    Science.gov (United States)

    Chen, Libo; Li, Fang; Zhuang, Hongming; Jing, Hongli; Du, Yanrong; Zeng, Zhengpei

    2009-03-01

    In this investigation, the efficacy of scintigraphy using (99m)Tc-labeled hydrazinonicotinyl-Tyr3-octreotide (HYNIC-TOC) in the evaluation of extraadrenal pheochromocytoma was assessed and compared with (131)I-labeled metaiodobenzylguanidine (MIBG) imaging. Ninety-seven patients who were suspected of having pheochromocytoma but showed no definite adrenal abnormalities on CT were evaluated by both (99m)Tc-HYNIC-TOC scintigraphy and (131)I-MIBG imaging. The results were compared with pathology findings or clinical follow-up. Of 58 patients proven to be without pheochromocytoma, (99m)Tc-HYNIC-TOC and (131)I-MIBG imaging excluded 56 and 58 patients, respectively, rendering a specificity of 96.6% for (99m)Tc-HYNIC-TOC imaging and 100% for (131)I-MIBG imaging. In the evaluation of adrenal pheochromocytoma (14 patients), the sensitivity of (99m)Tc-HYNIC-TOC scintigraphy and (131)I-MIBG imaging was 50% and 85.7%, respectively. However, in the evaluation of extraadrenal pheochromocytomas (25 patients), the sensitivity of (99m)Tc-HYNIC-TOC scintigraphy and (131)I-MIBG imaging was 96.0% and 72.0%, respectively. (99m)Tc-HYNIC-TOC scintigraphy is more sensitive than (131)I-MIBG imaging in the detection of extraadrenal pheochromocytomas.

  4. Extraction of lead and ridge characteristics from SAR images of sea ice

    Science.gov (United States)

    Vesecky, John F.; Smith, Martha P.; Samadani, Ramin

    1990-01-01

    Image-processing techniques for extracting the characteristics of lead and pressure ridge features in SAR images of sea ice are reported. The methods are applied to a SAR image of the Beaufort Sea collected from the Seasat satellite on October 3, 1978. Estimates of lead and ridge statistics are made, e.g., lead and ridge density (number of lead or ridge pixels per unit area of image) and the distribution of lead area and orientation as well as ridge length and orientation. The information derived is useful in both ice science and polar operations for such applications as albedo and heat and momentum transfer estimates, as well as ship routing and offshore engineering.

  5. Classification of multiple sclerosis patients by latent class analysis of magnetic resonance imaging characteristics.

    Science.gov (United States)

    Zwemmer, J N P; Berkhof, J; Castelijns, J A; Barkhof, F; Polman, C H; Uitdehaag, B M J

    2006-10-01

    Disease heterogeneity is a major issue in multiple sclerosis (MS). Classification of MS patients is usually based on clinical characteristics. More recently, a pathological classification has been presented. While clinical subtypes differ by magnetic resonance imaging (MRI) signature on a group level, a classification of individual MS patients based purely on MRI characteristics has not been presented so far. To investigate whether a restricted classification of MS patients can be made based on a combination of quantitative and qualitative MRI characteristics and to test whether the resulting subgroups are associated with clinical and laboratory characteristics. MRI examinations of the brain and spinal cord of 50 patients were scored for 21 quantitative and qualitative characteristics. Using latent class analysis, subgroups were identified, for whom disease characteristics and laboratory measures were compared. Latent class analysis revealed two subgroups that mainly differed in the extent of lesion confluency and MRI correlates of neuronal loss in the brain. Demographics and disease characteristics were comparable except for cognitive deficits. No correlations with laboratory measures were found. Latent class analysis offers a feasible approach for classifying subgroups of MS patients based on the presence of MRI characteristics. The reproducibility, longitudinal evolution and further clinical or prognostic relevance of the observed classification will have to be explored in a larger and independent sample of patients.

  6. Quantitative Evaluation of Scintillation Camera Imaging Characteristics of Isotopes Used in Liver Radioembolization

    Science.gov (United States)

    Elschot, Mattijs; Nijsen, Johannes Franciscus Wilhelmus; Dam, Alida Johanna; de Jong, Hugo Wilhelmus Antonius Maria

    2011-01-01

    Background Scintillation camera imaging is used for treatment planning and post-treatment dosimetry in liver radioembolization (RE). In yttrium-90 (90Y) RE, scintigraphic images of technetium-99m (99mTc) are used for treatment planning, while 90Y Bremsstrahlung images are used for post-treatment dosimetry. In holmium-166 (166Ho) RE, scintigraphic images of 166Ho can be used for both treatment planning and post-treatment dosimetry. The aim of this study is to quantitatively evaluate and compare the imaging characteristics of these three isotopes, in order that imaging protocols can be optimized and RE studies with varying isotopes can be compared. Methodology/Principal Findings Phantom experiments were performed in line with NEMA guidelines to assess the spatial resolution, sensitivity, count rate linearity, and contrast recovery of 99mTc, 90Y and 166Ho. In addition, Monte Carlo simulations were performed to obtain detailed information about the history of detected photons. The results showed that the use of a broad energy window and the high-energy collimator gave optimal combination of sensitivity, spatial resolution, and primary photon fraction for 90Y Bremsstrahlung imaging, although differences with the medium-energy collimator were small. For 166Ho, the high-energy collimator also slightly outperformed the medium-energy collimator. In comparison with 99mTc, the image quality of both 90Y and 166Ho is degraded by a lower spatial resolution, a lower sensitivity, and larger scatter and collimator penetration fractions. Conclusions/Significance The quantitative evaluation of the scintillation camera characteristics presented in this study helps to optimize acquisition parameters and supports future analysis of clinical comparisons between RE studies. PMID:22073149

  7. Bathymetry of Lake Superior

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Superior has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  8. Superior Hiking Trail Facilities

    Data.gov (United States)

    Minnesota Department of Natural Resources — Superior Hiking Trail main trail, spurs, and camp spurs for completed trail throughout Cook, Lake, St. Louis and Carlton counties. These data were collected with...

  9. Superior Hiking Trail

    Data.gov (United States)

    Minnesota Department of Natural Resources — Superior Hiking Trail main trail, spurs, and camp spurs for completed trail throughout Cook, Lake, St. Louis and Carlton counties. These data were collected with...

  10. Alternate superior Julia sets

    International Nuclear Information System (INIS)

    Yadav, Anju; Rani, Mamta

    2015-01-01

    Alternate Julia sets have been studied in Picard iterative procedures. The purpose of this paper is to study the quadratic and cubic maps using superior iterates to obtain Julia sets with different alternate structures. Analytically, graphically and computationally it has been shown that alternate superior Julia sets can be connected, disconnected and totally disconnected, and also fattier than the corresponding alternate Julia sets. A few examples have been studied by applying different type of alternate structures

  11. Cervicofacial tissue infarction in patients with acute invasive fungal sinusitis: prevalence and characteristic MR imaging findings.

    Science.gov (United States)

    Seo, Jungmin; Kim, Hyung-Jin; Chung, Seung-Kyu; Kim, Eunhee; Lee, Hanbee; Choi, Jin Wook; Cha, Ji Hoon; Kim, Hye Jung; Kim, Sung Tae

    2013-03-01

    Tissue infarction is known as one of the characteristic features of invasive fungal sinusitis (IFS). The purpose of this study was to investigate the prevalence and characteristic MR imaging findings of cervicofacial tissue infarction (CFTI) associated with acute IFS. We retrospectively reviewed MR images in 23 patients with histologically or microbiologically proven acute IFS. CFTI was defined as an area of lack of enhancement in and around the sinonasal tract on contrast-enhanced T1-weighted images. We divided CFTI into two groups, i.e., intrasinonasal and extrasinonasal. Particular attention was paid to the location of extrasinonasal CFTI and the signal intensity of CFTI on T1- and T2-weighted images. The presence of bone destruction on CT scans was also recorded. CFTI was found in 17 (74%) of 23 patients. All of these 17 patients had intrasinonasal CFTI, and 13 patients also had extrasinonasal CFTI. All 13 patients with extrasinonasal CFTI died of disease directly related to IFS. Various locations were involved in the 13 patients with extrasinonasal CFTI, including the orbit (n = 8), infratemporal fossa (n = 7), intracranial cavity (n = 3), and oral cavity and/or facial soft tissue (n = 4). Various signal intensities were noted at the area of CFTI on T1- and T2-weighted images. Bone destruction was found on CT scans in only 3 of 17 patients with CFTI. CFTI with preservation of the bony wall of the involved sinonasal tract may be a characteristic MR imaging finding of acute IFS. The mortality is very high once the lesion extends beyond the sinonasal tract.

  12. Textural characteristics of bone marrow blast nucleus images with different variants of acute lymphoblastic leukemia

    Science.gov (United States)

    Nikitaev, V. G.; Pronichev, A. N.; Polyakov, E. V.; Mozhenkova, A. V.; Tupitsin, N. N.; Frenkel, M. A.

    2018-01-01

    The paper describes the method of recognition of T - and B - variants of acute lymphoblastic leukemia in microscopic images of blood cells. The method is based on the use of texture characteristics of images. Experimental recognition accuracy evaluation is obtained from the sample of 38 patients (17 with T-ALL and 21 with B-ALL variants of acute lymphoblastic leukemia). The obtained results show the possibility of applying of the proposed approach to the differential diagnosis of T- and B- variants of acute lymphoblastic leukemia.

  13. Segmentation of head magnetic resonance image using self-mapping characteristic

    International Nuclear Information System (INIS)

    Madokoro, Hirokazu; Sato, Kazuhito; Ishii, Masaki; Kadowaki, Sakura

    2004-01-01

    In this paper, we proposed a segmentation method, for head magnetic resonance (MR) images. Our method used self mapping characteristic of a self-organization map (SOM), and it does not need the setting of the representative point by the operator. We considered the continuity and boundary in the brain tissues by the definition of the local block. In the evaluation experiment, we obtained the segmentation result of matching anatomical structure information. In addition, our method applied the clinical MR images, it was possible to obtain the effective and objective result for supporting the diagnosis of the brain atrophy by the doctor. (author)

  14. Characteristics of equatorial gravity waves derived from mesospheric airglow imaging observations

    Directory of Open Access Journals (Sweden)

    S. Suzuki

    2009-04-01

    Full Text Available We present the characteristics of small-scale (<100 km gravity waves in the equatorial mesopause region derived from OH airglow imaging observations at Kototabang (100.3° E, 0.2° S, Indonesia, from 2002 to 2005. We adopted a method that could automatically detect gravity waves in the airglow images using two-dimensional cross power spectra of gravity waves. The propagation directions of the waves were likely controlled by zonal filtering due to stratospheric mean winds that show a quasi-biennial oscillation (QBO and the presence of many wave sources in the troposphere.

  15. Model-based estimation of breast percent density in raw and processed full-field digital mammography images from image-acquisition physics and patient-image characteristics

    Science.gov (United States)

    Keller, Brad M.; Nathan, Diane L.; Conant, Emily F.; Kontos, Despina

    2012-03-01

    Breast percent density (PD%), as measured mammographically, is one of the strongest known risk factors for breast cancer. While the majority of studies to date have focused on PD% assessment from digitized film mammograms, digital mammography (DM) is becoming increasingly common, and allows for direct PD% assessment at the time of imaging. This work investigates the accuracy of a generalized linear model-based (GLM) estimation of PD% from raw and postprocessed digital mammograms, utilizing image acquisition physics, patient characteristics and gray-level intensity features of the specific image. The model is trained in a leave-one-woman-out fashion on a series of 81 cases for which bilateral, mediolateral-oblique DM images were available in both raw and post-processed format. Baseline continuous and categorical density estimates were provided by a trained breast-imaging radiologist. Regression analysis is performed and Pearson's correlation, r, and Cohen's kappa, κ, are computed. The GLM PD% estimation model performed well on both processed (r=0.89, p<0.001) and raw (r=0.75, p<0.001) images. Model agreement with radiologist assigned density categories was also high for processed (κ=0.79, p<0.001) and raw (κ=0.76, p<0.001) images. Model-based prediction of breast PD% could allow for a reproducible estimation of breast density, providing a rapid risk assessment tool for clinical practice.

  16. MR imaging characteristics in primary lymphoma of bone with emphasis on non-aggressive appearance

    International Nuclear Information System (INIS)

    Heyning, Fenna H.; Kroon, Herman M.J.A.; Hogendoorn, Pancras C.W.; Taminiau, Antonie H.M.; Woude, Henk-Jan van der

    2007-01-01

    To assess the heterogeneity of magnetic resonance (MR) imaging characteristics in primary lymphoma of bone (PLB), in particular the non-aggressive appearance. In a retrospective study, MR imaging features were analyzed in 29 patients with histologically proven PLB. The following parameters were evaluated: tumor size, bone marrow and extension into soft tissues, signal characteristics of bone marrow and soft-tissue components, including enhancement, and involvement of cortical bone (complete disruption, focal destruction, permeative destruction and cortical thickening). PLB presented with extension into the soft tissue in 22 (76%) of 29 patients, was only subtle in three of these 22 patients, and was absent in seven patients. Signal intensity (SI) of the soft-tissue part was most frequently homogeneously isointense with muscle on T1-weighted images (90%) and high on T2-weighted images (91%). Enhancement was predominantly homogeneous and diffuse (82%). In 93% of patients cortical bone appeared abnormal: among those patients complete cortical disruption was seen in 28%, with extension into soft tissues in all but one patient; a permeative pattern of destruction was present in 52% of patients, 66% of these had an associated soft-tissue mass. Two patients with normal-appearing cortical bone had no extension into soft tissues. In two patients focal cortical destruction was noticed; in one patient cortical bone was homogeneously thickened, and in one patient PLB was selectively localized within the cortical bone. SI of the bone marrow tumor component was more frequently heterogeneous (in 54%), compared with the soft-tissue component, being high on T2-weighted images in 89%, intermediate in 7% and low in 4%. Similarly, enhancement was heterogeneous in 59%. The MR imaging appearance of PLB is variable. In 31% of PLB patients, the tumor was intra-osseous, with linear cortical signal abnormalities or even normal-appearing or thickened cortical bone without soft-tissue mass

  17. Primary diaphyseal osteosarcoma in long bones: Imaging features and tumor characteristics

    International Nuclear Information System (INIS)

    Wang, Cheng-Sheng; Yin, Qi-Hua; Liao, Jin-Sheng; Lou, Jiang-Hua; Ding, Xiao-Yi; Zhu, Yan-Bo; Chen, Ke-Min

    2012-01-01

    Objective: This study aims to assess retrospectively the imaging features of diaphyseal osteosarcoma and compare its characteristics with that of metaphyseal osteosarcoma. Materials and methods: Eighteen pathologically confirmed diaphyseal osteosarcomas were reviewed. Images of X-ray (n = 18), CT (n = 12) and MRI (n = 15) were evaluated by two radiologists. Differences among common radiologic findings of X-ray, CT and MRI, and between diaphyseal osteosarcomas and metaphyseal osteosarcomas in terms of tumor characteristics were compared. Results: The common imaging features of diaphyseal osteosarcoma were bone destruction, lamellar periosteal reaction with/without Codman triangle, massive soft tissue mass/swelling, neoplastic bone and/or calcification. CT and MRI had a higher detection rate in detecting bone destruction (P = 0.001) as compared with that of X-ray. X-ray and CT resulted in a higher percentage in detecting periosteal reaction (P = 0.018) and neoplastic bone and/or calcification (P = 0.043) as compared with that of MRI. There was no difference (P = 0.179) in detecting soft tissue mass among three imaging modalities. When comparing metaphyseal osteosarcoma to diaphyseal osteosarcoma, the latter had the following characteristics: a higher age of onset (P = 0.022), a larger extent of tumor (P = 0.018), a more osteolytic radiographic pattern (P = 0.043). Conclusion: As compared with metaphyseal osteosarcoma, diaphysial osteosarcoma is a special location of osteosarcoma with a lower incidence, a higher age of onset, a larger extent of tumor, a more osteolytic radiographic pattern. The osteoblastic and mixed types are diagnosed easily, but the osteolytic lesion should be differentiated from Ewing sarcoma. X-ray, CT and MRI can show imaging features from different aspects with different detection rates.

  18. Prosopomorphic vessels from Moesia Superior

    Directory of Open Access Journals (Sweden)

    Nikolić Snežana

    2008-01-01

    Full Text Available The prosopomorphic vessels from Moesia Superior had the form of beakers varying in outline but similar in size. They were wheel-thrown, mould-made or manufactured by using a combination of wheel-throwing and mould-made appliqués. Given that face vessels are considerably scarcer than other kinds of pottery, more than fifty finds from Moesia Superior make an enviable collection. In this and other provinces face vessels have been recovered from military camps, civilian settlements and necropolises, which suggests that they served more than one purpose. It is generally accepted that the faces-masks gave a protective role to the vessels, be it to protect the deceased or the family, their house and possessions. More than forty of all known finds from Moesia Superior come from Viminacium, a half of that number from necropolises. Although tangible evidence is lacking, there must have been several local workshops producing face vessels. The number and technological characteristics of the discovered vessels suggest that one of the workshops is likely to have been at Viminacium, an important pottery-making centre in the second and third centuries.

  19. Adaptive local backlight dimming algorithm based on local histogram and image characteristics

    DEFF Research Database (Denmark)

    Nadernejad, Ehsan; Burini, Nino; Korhonen, Jari

    2013-01-01

    -off between power consumption and image quality preservation than the other algorithms representing the state of the art among feature based backlight algorithms. © (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.......Liquid Crystal Display (LCDs) with Light Emitting Diode (LED) backlight is a very popular display technology, used for instance in television sets, monitors and mobile phones. This paper presents a new backlight dimming algorithm that exploits the characteristics of the target image......, such as the local histograms and the average pixel intensity of each backlight segment, to reduce the power consumption of the backlight and enhance image quality. The local histogram of the pixels within each backlight segment is calculated and, based on this average, an adaptive quantile value is extracted...

  20. Experimental investigation on the caries characteristic of dental tissues by photothermal radiometry scanning imaging

    Science.gov (United States)

    Wang, Fei; Liu, Jun-yan; Wang, Xiao-chun; Wang, Yang

    2018-03-01

    In this paper, a one-dimensional (1D) thermal-wave model coupled diffuse-photon-density-wave for three-layer dental tissues using modulated laser stimulation was employed to illustrate the relationship between dental caries characteristic (i.e. caries layer thickness, optical absorption coefficient and optical scattering coefficient) and photothermal radiometry (PTR) signal. Experimental investigation of artificial caries was carried out using PTR scanning imaging. The PTR amplitude and phase delay were increased with dental demineralized treatment. The local caries characteristic parameters were obtained by the best-fitting method based on the 1D thermal-wave model. The PTR scanning imaging measurements illustrated that the optical absorption coefficient and scattering coefficient of caries region were much higher than those of the healthy enamel area. The demineralization thickness of caries region was measured by PTR scanning imaging and its average value shows in good agreement with the digital microscope. Experimental results show that PTR scanning imaging has the merits of high contrast for local inhomogeneity of dental caries; furthermore, this method is an allowance to provide a flexibility for non-contact quantitative evaluation of dental caries.

  1. Digital image analysis of Ki67 in hot spots is superior to both manual Ki67 and mitotic counts in breast cancer.

    Science.gov (United States)

    Stålhammar, Gustav; Robertson, Stephanie; Wedlund, Lena; Lippert, Michael; Rantalainen, Mattias; Bergh, Jonas; Hartman, Johan

    2018-05-01

    During pathological examination of breast tumours, proliferative activity is routinely evaluated by a count of mitoses. Adding immunohistochemical stains of Ki67 provides extra prognostic and predictive information. However, the currently used methods for these evaluations suffer from imperfect reproducibility. It is still unclear whether analysis of Ki67 should be performed in hot spots, in the tumour periphery, or as an average of the whole tumour section. The aim of this study was to compare the clinical relevance of mitoses, Ki67 and phosphohistone H3 in two cohorts of primary breast cancer specimens (total n = 294). Both manual and digital image analysis scores were evaluated for sensitivity and specificity for luminal B versus A subtype as defined by PAM50 gene expression assays, for high versus low transcriptomic grade, for axillary lymph node status, and for prognostic value in terms of prediction of overall and relapse-free survival. Digital image analysis of Ki67 outperformed the other markers, especially in hot spots. Tumours with high Ki67 expression and high numbers of phosphohistone H3-positive cells had significantly increased hazard ratios for all-cause mortality within 10 years from diagnosis. Replacing manual mitotic counts with digital image analysis of Ki67 in hot spots increased the differences in overall survival between the highest and lowest histological grades, and added significant prognostic information. Digital image analysis of Ki67 in hot spots is the marker of choice for routine analysis of proliferation in breast cancer. © 2017 John Wiley & Sons Ltd.

  2. MR imaging characteristics of osteoradionecrosis of the pelvis after radiation therapy on gynecological tumors

    International Nuclear Information System (INIS)

    Schmitt, J.; Abolmaali, N.D.; Jacobi, V.; Vogl, T.J.; Hoeller, U.; Schiemann, M.; Obert, K.

    2002-01-01

    Purpose: To describe MR imaging characteristics of osteoradionecrosis (ORN) of the pelvis as a result of radiation therapy (RT) on gynecological tumors. Material and Methods: Radiography, computed tomography (CT) and magnetic resonance imaging (MRI) were performed on 9 women (mean age 67.5 years) with gynecological tumors to identify ORN. T 1 - and T 2 -weighted sequences and contrast-enhanced t 1 -weighted sequences with and without fat saturation were used. The patients began developing pain after the completion of RT indicating a possible ORN a which time MRI was performed. MR images were correlated with the results of clinical examinations. Results: Depending on the time elapsed after RT, ORN presented with different signal intensities. The acquired images suggested that signal changes in T 2 -weighted images as well as the different enhancement behaviour of ORN could be dependent on the time elapsed after RT. Visualisation of the affected regions was best achieved with fat-saturated T 1 -weighted sequences. CT showed increased density in the affected regions corresponding to osteosclerosis. In all cases the sacroiliac joint was affected, some times bilateraly. Conclusion: MRI is helpful in detecting and characterizing ORN. Changes in signal intensity, based on histopathological tissue changes could make a chronological classification possible. (orig.) [de

  3. [Investigation of the hyperspectral image characteristics of wheat leaves under different stress].

    Science.gov (United States)

    Zhang, Dong-Yan; Zhang, Jing-Cheng; Zhu, Da-Zhou; Wang, Ji-Hua; Luo, Ju-Hua; Zhao, Jin-Ling; Huang, Wen-Jiang

    2011-04-01

    The diagnosis of growing status and vigor of crops under various stresses is an important step in precision agriculture. Hyperspectral imaging technology has the advantage of providing both spectral and spatial information simultaneously, and has become a research hot spot. In the present study, auto-development of the pushbroom imaging spectrometer (PIS) was utilized to collect hyperspectral images of wheat leaves which suffer from shortage of nutrient, pest and disease stress. The hyperspectral cube was processed by the method of pixel average step by step to highlight the spectral characteristics, which facilitate the analysis based on the differences of leaves reflectance. The results showed that the hyperspectra of leaves from different layers can display nutrient differences, and recognize intuitively different stress extent by imaging figures. With the 2 nanometer spectral resolution and millimeter level spatial resolution of PIS, the number of disease spot can be qualitatively calculated when crop is infected with diseases, and, the area of plant disease could also be quantitatively analyzed; when crop suffered from pest and insect, the spectral information of leaves with single aphid and aphids can be detected by PIS, which provides a new means to quantitatively detect the aphid destroying of wheat leaf. The present study demonstrated that hyperspecral imaging has a great potential in quantitative and qualitative analysis of crop growth.

  4. New and superior adrenal imaging agent, 131I-6β-iodomethyl-19-nor-cholesterol (NP-59): evaluation in humans

    International Nuclear Information System (INIS)

    Sarkar, S.D.; Cohen, E.L.; Beierwaltes, W.H.; Ice, R.D.; Cooper, R.; Gold, E.N.

    1977-01-01

    We have reported tissue distribution studies in rats and dogs with a new adrenal imaging agent, 131 I-6β-iodomethyl-19-nor-cholesterol (NP-59). This agent concentrated five times higher in the adrenal cortex than 131 I-19-iodocholesterol without increased concentration in non-adrenal tissues. We now report in 34 patients, the findings on scintigraphy with NP-59 compared with angiograms and/or adrenal vein hormone levels and histopathology, including 13 patients with hypercortisolism, 12 with primary aldosteronism, 2 with low renin hypertension, 5 with catecholamine excess, 1 with a liver metastasis from an aldosterone producing adrenal cortical carcinoma, and 1 with anaplastic adrenal cortical carcinoma. NP-59 adrenal cortical uptake was more rapid and intense and background activity was less prominent, allowing earlier and more definite interpretation of images than was possible with 131 I-19-iodocholesterol

  5. Receiver operating characteristic analysis for the detection of simulated microcalcifications on mammograms using hardcopy images

    International Nuclear Information System (INIS)

    Lai, C J; Shaw, Chris C; Whitman, Gary J; Yang, Wei T; Dempsey, Peter J; Nguyen, Victoria; Ice, Mary F

    2006-01-01

    The aim of this study was to compare mammography systems based on three different detectors-a conventional screen-film (SF) combination, an a-Si/CsI flat-panel (FP)-based detector, and a charge-coupled device (CCD)-based x-ray phosphor-based detector-for their performance in detecting simulated microcalcifications (MCs). 112-150 μm calcium carbonate grains were used to simulate MCs and were overlapped with a slab phantom of simulated 50% adipose/50% glandular breast tissue-equivalent material referred to as the uniform background. For the tissue structure background, 200-250 μm calcium carbonate grains were used and overlapped with an anthropomorphic breast phantom. All MC phantom images were acquired with and without magnification (1.8X). The hardcopy images were reviewed by five mammographers. A five-point confidence level rating was used to score each detection task. Receiver operating characteristic (ROC) analysis was performed, and the areas under the ROC curves (A z s) were used to compare the performances of the three mammography systems under various conditions. The results showed that, with a uniform background and contact images, the FP-based system performed significantly better than the SF and the CCD-based systems. For magnified images with a uniform background, the SF and the FP-based systems performed equally well and significantly better than the CCD-based system. With tissue structure background and contact images, the SF system performed significantly better than the FP and the CCD-based systems. With magnified images and a tissue structure background, the SF and the CCD-based systems performed equally well and significantly better than the FP-based system. In the detection of MCs in the fibroglandular and the heterogeneously dense regions, no significant differences were found except that the SF system performed significantly better than the CCD-based system in the fibroglandular regions for the contact images

  6. MRI image characteristics of materials implanted at sellar region after transsphenoidal resection of pituitary tumours

    International Nuclear Information System (INIS)

    Bladowska, J.; Sasiadek, M.; Bednarek-Tupikowska, G.; Sokolska, V.; Badowski, R.; Moron, K.; Bonicki, W.

    2010-01-01

    Background: Post-surgical evaluation of the pituitary gland in MRI is difficult because of a change in anatomical conditions. It depends also on numerous other factors, including: size and expansion of the tumour before surgery, type of surgical access, quality and volume of implanted materials and time of its resorption. The purpose was to demonstrate the characteristics of the implanted materials on MRI performed after transsphenoidal resection of pituitary tumours and to identify imaging criteria helpful in differential diagnosis of masses within the sellar region. Material/Methods: One hundred and fifty-four patients after transsphenoidal resection of pituitary tumours were included in the study. In general, 469 MRI examinations were performed with a 1.5 T scanner. We obtained T1-weighted sagittal and coronal, enhanced and unenhanced images. In 102 cases, additional T2-weighted coronal, unenhanced images with 1.5 T unit were obtained as well. Results: The implanted materials appeared in 95 patient: fat in 86 and muscle with fascia in 3 patients. We could recognise implanted muscle and fascia in T2-weighted images, because of high signal intensity of the degenerating muscle and the line of low signal representing fascia. The implanted titanium mesh was found in 4 patients. Haemostatic materials were visible only in 2 patients in examinations performed at an early postoperative stage (1 month after the procedure). Conclusions: The knowledge of MRI characteristics of the materials implanted at the sellar region is very important in postoperative diagnosis of pituitary tumours and may help discriminate between tumorous and non-tumorous involvement of the sellar region. Some implanted materials, like fat, could be seen on MRI for as long as 10 years after the operation, others, like haemostatic materials, for only 1 month after surgery. T2-weighted imaging is a useful assessment method of the implanted muscle and fascia for a long time after surgery. (authors)

  7. Peracetic acid as a superior oxidant for preparation of [123I]IBZM: a potential dopamine D-2 receptor imaging agent

    International Nuclear Information System (INIS)

    Kung, Meiping; Kung, H.F.

    1989-01-01

    Various oxidizing agents: chloramine-T, hydrogen peroxide, sodium persulfate, m-chloroperoxybenzoic acid and peracetic acid were examined as the oxidant for preparing radioiodinated IBZM ((S)-(-)-3-iodo-2-hydroxy-6-methoxy-N-[(1-ethyl-2-pyrrolidinyl)methyl]benzami de), which is a useful dopamine D-2 receptor imaging agent. Of all the oxidizing agents tested, peracetic acid appears to be the best agent for no-carrier added radioiodination. The advantages of using peracetic acid as the oxidant for the preparation of [ 125 I] or [ 123 I] IBZM include: high radiochemical yield, high radiochemical purity, and short reaction time at room temperature. (Author)

  8. Review on the characteristics of radiation detectors for dosimetry and imaging

    International Nuclear Information System (INIS)

    Seco, Joao; Clasie, Ben; Partridge, Mike

    2014-01-01

    The enormous advances in the understanding of human anatomy, physiology and pathology in recent decades have led to ever-improving methods of disease prevention, diagnosis and treatment. Many of these achievements have been enabled, at least in part, by advances in ionizing radiation detectors. Radiology has been transformed by the implementation of multi-slice CT and digital x-ray imaging systems, with silver halide films now largely obsolete for many applications. Nuclear medicine has benefited from more sensitive, faster and higher-resolution detectors delivering ever-higher SPECT and PET image quality. PET/MR systems have been enabled by the development of gamma ray detectors that can operate in high magnetic fields. These huge advances in imaging have enabled equally impressive steps forward in radiotherapy delivery accuracy, with 4DCT, PET and MRI routinely used in treatment planning and online image guidance provided by cone-beam CT. The challenge of ensuring safe, accurate and precise delivery of highly complex radiation fields has also both driven and benefited from advances in radiation detectors. Detector systems have been developed for the measurement of electron, intensity-modulated and modulated arc x-ray, proton and ion beams, and around brachytherapy sources based on a very wide range of technologies. The types of measurement performed are equally wide, encompassing commissioning and quality assurance, reference dosimetry, in vivo dosimetry and personal and environmental monitoring. In this article, we briefly introduce the general physical characteristics and properties that are commonly used to describe the behaviour and performance of both discrete and imaging detectors. The physical principles of operation of calorimeters; ionization and charge detectors; semiconductor, luminescent, scintillating and chemical detectors; and radiochromic and radiographic films are then reviewed and their principle applications discussed. Finally, a general

  9. Accurate Analysis of Target Characteristic in Bistatic SAR Images: A Dihedral Corner Reflectors Case.

    Science.gov (United States)

    Ao, Dongyang; Li, Yuanhao; Hu, Cheng; Tian, Weiming

    2017-12-22

    The dihedral corner reflectors are the basic geometric structure of many targets and are the main contributions of radar cross section (RCS) in the synthetic aperture radar (SAR) images. In stealth technologies, the elaborate design of the dihedral corners with different opening angles is a useful approach to reduce the high RCS generated by multiple reflections. As bistatic synthetic aperture sensors have flexible geometric configurations and are sensitive to the dihedral corners with different opening angles, they specially fit for the stealth target detections. In this paper, the scattering characteristic of dihedral corner reflectors is accurately analyzed in bistatic synthetic aperture images. The variation of RCS with the changing opening angle is formulated and the method to design a proper bistatic radar for maximizing the detection capability is provided. Both the results of the theoretical analysis and the experiments show the bistatic SAR could detect the dihedral corners, under a certain bistatic angle which is related to the geometry of target structures.

  10. Characteristic findings in images of extra-pancreatic lesions associated with autoimmune pancreatitis

    Energy Technology Data Exchange (ETDEWEB)

    Fujinaga, Yasunari, E-mail: fujinaga@shinshu-u.ac.jp [Department of Radiology, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621 (Japan); Kadoya, Masumi [Department of Radiology, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621 (Japan); Kawa, Shigeyuki [Center of Health, Safety and Environmental Management, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621 (Japan); Hamano, Hideaki [Department of Medicine, Gastroenterology, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621 (Japan); Ueda, Kazuhiko; Momose, Mitsuhiro; Kawakami, Satoshi; Yamazaki, Sachie; Hatta, Tomoko; Sugiyama, Yukiko [Department of Radiology, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, 390-8621 (Japan)

    2010-11-15

    Purpose: Autoimmune pancreatitis is a unique form of chronic pancreatitis characterized by a variety of extra-pancreatic involvements which are frequently misdiagnosed as lesions of corresponding organs. The purpose of this study was to clarify the diagnostic imaging features of extra-pancreatic lesions associated with autoimmune pancreatitis. Materials and methods: We retrospectively analyzed diagnostic images of 90 patients with autoimmune pancreatitis who underwent computer-assisted tomography, magnetic resonance imaging, and/or gallium-67 scintigraphy before steroid therapy was initiated. Results: AIP was frequently (92.2%) accompanied by a variety of extra-pancreatic lesions, including swelling of lachrymal and salivary gland lesions (47.5%), lung hilar lymphadenopathy (78.3%), a variety of lung lesions (51.2%), wall thickening of bile ducts (77.8%), peri-pancreatic or para-aortic lymphadenopathy (56.0%), retroperitoneal fibrosis (19.8%), a variety of renal lesions (14.4%), and mass lesions of the ligamentum teres (2.2%). Characteristic findings in CT and MRI included lymphadenopathies of the hilar, peri-pancreatic, and para-aortic regions; wall thickening of the bile duct; and soft tissue masses in the kidney, ureters, aorta, paravertebral region, ligamentum teres, and orbit. Conclusions: Recognition of the diagnostic features in the images of various involved organs will assist in the diagnosis of autoimmune pancreatitis and in differential diagnoses between autoimmune pancreatitis-associated extra-pancreatic lesions and lesions due to other pathologies.

  11. A method for the automated detection phishing websites through both site characteristics and image analysis

    Science.gov (United States)

    White, Joshua S.; Matthews, Jeanna N.; Stacy, John L.

    2012-06-01

    Phishing website analysis is largely still a time-consuming manual process of discovering potential phishing sites, verifying if suspicious sites truly are malicious spoofs and if so, distributing their URLs to the appropriate blacklisting services. Attackers increasingly use sophisticated systems for bringing phishing sites up and down rapidly at new locations, making automated response essential. In this paper, we present a method for rapid, automated detection and analysis of phishing websites. Our method relies on near real-time gathering and analysis of URLs posted on social media sites. We fetch the pages pointed to by each URL and characterize each page with a set of easily computed values such as number of images and links. We also capture a screen-shot of the rendered page image, compute a hash of the image and use the Hamming distance between these image hashes as a form of visual comparison. We provide initial results demonstrate the feasibility of our techniques by comparing legitimate sites to known fraudulent versions from Phishtank.com, by actively introducing a series of minor changes to a phishing toolkit captured in a local honeypot and by performing some initial analysis on a set of over 2.8 million URLs posted to Twitter over a 4 days in August 2011. We discuss the issues encountered during our testing such as resolvability and legitimacy of URL's posted on Twitter, the data sets used, the characteristics of the phishing sites we discovered, and our plans for future work.

  12. Gadoxetic acid-enhanced magnetic resonance imaging characteristics of hepatocellular carcinoma occurring in liver transplants

    International Nuclear Information System (INIS)

    Kim, Mimi; Kang, Tae Wook; Jeong, Woo Kyoung; Kim, Young Kon; Kim, Seong Hyun; Kim, Jong Man; Sinn, Dong Hyun; Kim, Min-Ji; Jung, Sin-ho

    2017-01-01

    Characteristics of hepatocellular carcinoma (HCC) on magnetic resonance (MR) images were compared in patients who did or did not undergo liver transplantation (LT), and we evaluated the relationship of these findings with overall survival (OS) and time-to-tumour recurrence (TTR) after transplantation. The enhancement pattern of gadoxetic acid-enhanced MR images of 25 patients with recurrent HCCs (LT group) and 25 surgically confirmed HCC patients in the non-transplanted (control) group were compared. Typical enhancement was defined as 1) arterial enhancement and delayed wash-out and 2) absence of typical features of cholangiocarcinoma consisting of arterial rim enhancement and target appearance on hepatobiliary phase images. OS and TTR were analyzed in the LT group according to these patterns using the log-rank test. HCCs in the LT group significantly more often had an atypical enhancement pattern (16/25, 64.0%) than those in the control group (5/25, 20.0%; p = 0.004). However, OS and TTR did not differ significantly according to these enhancement patterns of recurrent HCC (p > 0.05). Although enhancement patterns of recurrent HCC in transplanted liver did not affect OS and TTR, these HCCs that arise after LT frequently revealed atypical enhancement on gadoxetic acid-enhanced MR imaging. (orig.)

  13. Gadoxetic acid-enhanced magnetic resonance imaging characteristics of hepatocellular carcinoma occurring in liver transplants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Mimi [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of); Hanyang University of Hospital, Department of Radiology, Seoul (Korea, Republic of); Kang, Tae Wook; Jeong, Woo Kyoung; Kim, Young Kon; Kim, Seong Hyun [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea, Republic of); Kim, Jong Man [Sungkyunkwan University School of Medicine, Department of Surgery, Samsung Medical Center, Seoul (Korea, Republic of); Sinn, Dong Hyun [Sungkyunkwan University School of Medicine, Division of hepatology, Department of Medicine, Samsung Medical Center, Seoul (Korea, Republic of); Kim, Min-Ji; Jung, Sin-ho [Samsung Medical Center, Biostatics and Clinical Epidemiology Center, Seoul (Korea, Republic of)

    2017-08-15

    Characteristics of hepatocellular carcinoma (HCC) on magnetic resonance (MR) images were compared in patients who did or did not undergo liver transplantation (LT), and we evaluated the relationship of these findings with overall survival (OS) and time-to-tumour recurrence (TTR) after transplantation. The enhancement pattern of gadoxetic acid-enhanced MR images of 25 patients with recurrent HCCs (LT group) and 25 surgically confirmed HCC patients in the non-transplanted (control) group were compared. Typical enhancement was defined as 1) arterial enhancement and delayed wash-out and 2) absence of typical features of cholangiocarcinoma consisting of arterial rim enhancement and target appearance on hepatobiliary phase images. OS and TTR were analyzed in the LT group according to these patterns using the log-rank test. HCCs in the LT group significantly more often had an atypical enhancement pattern (16/25, 64.0%) than those in the control group (5/25, 20.0%; p = 0.004). However, OS and TTR did not differ significantly according to these enhancement patterns of recurrent HCC (p > 0.05). Although enhancement patterns of recurrent HCC in transplanted liver did not affect OS and TTR, these HCCs that arise after LT frequently revealed atypical enhancement on gadoxetic acid-enhanced MR imaging. (orig.)

  14. Determination of tire cross-sectional geometric characteristics from a digitally scanned image

    Science.gov (United States)

    Danielson, Kent T.

    1995-08-01

    A semi-automated procedure is described for the accurate determination of geometrical characteristics using a scanned image of the tire cross-section. The procedure can be useful for cases when CAD drawings are not available or when a description of the actual cured tire is desired. Curves representing the perimeter of the tire cross-section are determined by an edge tracing scheme, and the plyline and cord-end positions are determined by locations of color intensities. The procedure provides an accurate description of the perimeter of the tire cross-section and the locations of plylines and cord-ends. The position, normals, and curvatures of the cross-sectional surface are included in this description. The locations of the plylines provide the necessary information for determining the ply thicknesses and relative position to a reference surface. Finally, the locations of the cord-ends provide a means to calculate the cord-ends per inch (epi). Menu driven software has been developed to facilitate the procedure using the commercial code, PV-Wave by Visual Numerics, Inc., to display the images. From a single user interface, separate modules are executed for image enhancement, curve fitting the edge trace of the cross-sectional perimeter, and determining the plyline and cord-end locations. The code can run on SUN or SGI workstations and requires the use of a mouse to specify options or identify items on the scanned image.

  15. Hyperspectral optical imaging of human iris in vivo: characteristics of reflectance spectra

    Science.gov (United States)

    Medina, José M.; Pereira, Luís M.; Correia, Hélder T.; Nascimento, Sérgio M. C.

    2011-07-01

    We report a hyperspectral imaging system to measure the reflectance spectra of real human irises with high spatial resolution. A set of ocular prosthesis was used as the control condition. Reflectance data were decorrelated by the principal-component analysis. The main conclusion is that spectral complexity of the human iris is considerable: between 9 and 11 principal components are necessary to account for 99% of the cumulative variance in human irises. Correcting image misalignments associated with spontaneous ocular movements did not influence this result. The data also suggests a correlation between the first principal component and different levels of melanin present in the irises. It was also found that although the spectral characteristics of the first five principal components were not affected by the radial and angular position of the selected iridal areas, they affect the higher-order ones, suggesting a possible influence of the iris texture. The results show that hyperspectral imaging in the iris, together with adequate spectroscopic analyses provide more information than conventional colorimetric methods, making hyperspectral imaging suitable for the characterization of melanin and the noninvasive diagnosis of ocular diseases and iris color.

  16. Performance characteristics of mobile MOSFET dosimeter for kilovoltage X-rays used in image guided radiotherapy.

    Science.gov (United States)

    Kumar, A Sathish; Singh, I Rabi Raja; Sharma, S D; Ravindran, B Paul

    2015-01-01

    The main objective of this study was to investigate the characteristics of metal oxide semiconductor field effect transistor (MOSFET) dosimeter for kilovoltage (kV) X-ray beams in order to perform the in vivo dosimetry during image guidance in radiotherapy. The performance characteristics of high sensitivity MOSFET dosimeters were investigated for 80, 90, 100, 110, 120, and 125 kV X-ray beams used for imaging in radiotherapy. This study was performed using Clinac 2100 C/D medical electron linear accelerator with on-board imaging and kV cone beam computed tomography system. The characteristics studied in this work include energy dependence, angular dependence, and linearity. The X-ray beam outputs were measured as per American Association of Physicists in Medicine (AAPM) TG 61 recommendations using PTW parallel plate (PP) ionization chamber, which was calibrated in terms of air kerma (Nk) by the National Standard Laboratory. The MOSFET dosimeters were calibrated against the PP ionization chamber for all the kV X-ray beams and the calibration coefficient was found to be 0.11 cGy/mV with a standard deviation of about ±1%. The response of MOSFET was found to be energy independent for the kV X-ray energies used in this study. The response of the MOSFET dosimeter was also found independent of angle of incidence for the gantry angles in the range of 0° to 360° in-air as well as at 3 cm depth in tissue equivalent phantom.

  17. Gadoxetic acid disodium-enhanced MR imaging of cholangiolocellular carcinoma of the liver. Imaging characteristics and histopathological correlations

    Energy Technology Data Exchange (ETDEWEB)

    Haradome, Hiroki; Toda, Yusuke [Nihon University School of Medicine, Department of Radiology, Tokyo (Japan); Unno, Toshiyuki [Showa General Hospital, Department of Radiology, Koganei (Japan); Morisaka, Hiroyuki; Ichikawa, Tomoaki [Saitama Medical University International Medical Center, Department of Radiology, Saitama (Japan); Kwee, Thomas C. [UMC Groningen, Department of Radiology, Groningen (Netherlands); Kondo, Hiroshi [Teikyo University School of Medicine, Department of Radiology, Tokyo (Japan); Sano, Keiji [Teikyo University School of Medicine, Department of Surgery, Tokyo (Japan); Kondo, Fukuo [Teikyo University Hospital, Department of Pathology, Tokyo (Japan); Sugitani, Masahiko [Nihon University School of Medicine, Department of Pathology, Tokyo (Japan); Takayama, Tadatoshi [Nihon University School of Medicine, Department of Digestive Surgery, Tokyo (Japan)

    2017-11-15

    To review the gadoxetic acid disodium (EOB)-enhanced magnetic resonance (MR) imaging features of cholangiolocellular carcinoma (CoCC) of the liver and compare them with those of hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). EOB-enhanced MR images of 19 patients with CoCC, 23 with ICC, and 51 with HCC were retrospectively evaluated qualitatively and quantitatively. Univariate and multivariate analyses were performed to determine the characteristic MR features of CoCC with histopathological-imaging correlation. Multivariate logistic regression analysis showed that dot-/band-shaped internal enhancement during the arterial and portal phases (P < 0.001), and larger arterial ring enhancement ratio (CoCC, 0.13 ± 0.04; ICC, 0.074 ± 0.04; P = 0.013) were significantly independently associated with CoCC in contrast to ICC, whereas several MR features including progressive enhancement during the portal and late phases (P < 0.001), target appearance in the hepatocyte phase (P = 0.004), and vessel penetration (P = 0.013) were significantly more frequently associated with CoCC than HCC. The dot-/band-like internal enhancement (78.9% of CoCCs) histopathologically corresponded to the tumour cell nest with vascular proliferations and retained Glisson's sheath structure. EOB-enhanced MR features of CoCC largely differ from those of HCC but are similar to those of ICC. However, the finding of thicker arterial ring enhancement with dot-/band-like internal enhancement could help differentiate CoCC from ICC. (orig.)

  18. Self and Superior Assessment.

    Science.gov (United States)

    1986-06-01

    model of the self-evaluation process as it differs from the evaluation process used by superiors. Symbolic Interactionism One view of self assessment is...supplied by the symbolic interactionists (Cooley, 1902; Head, 1934), who state that self perceptions are generated largely from individuals...disagreements remained even immediately after an appraisal interview in which a great deal of feedback was given. Research on the symbolic interactionist

  19. Currarino triad: characteristic appearances on magnetic resonance imaging and plain radiography

    International Nuclear Information System (INIS)

    Low, G.; Irwin, G.J; Maroo, S.V.; Haddock, G.

    2006-01-01

    The Currarino triad is a complex anomaly consisting of an anorectal malformation, a sacral bone defect and a presacral mass. It was first described in 1981 and since then, approximately 250 cases have been reported. Radiology has an important part to play in the diagnosis of this entity, as the imaging features are characteristic. We report a case of Currarino triad in an infant who presented with intractable constipation and discuss relevant MRI and plain radiography findings Copyright (2006) Blackwell Publishing Asia Pty Ltd

  20. Using Functional or Structural Magnetic Resonance Images and Personal Characteristic Data to Identify ADHD and Autism.

    Directory of Open Access Journals (Sweden)

    Sina Ghiassian

    Full Text Available A clinical tool that can diagnose psychiatric illness using functional or structural magnetic resonance (MR brain images has the potential to greatly assist physicians and improve treatment efficacy. Working toward the goal of automated diagnosis, we propose an approach for automated classification of ADHD and autism based on histogram of oriented gradients (HOG features extracted from MR brain images, as well as personal characteristic data features. We describe a learning algorithm that can produce effective classifiers for ADHD and autism when run on two large public datasets. The algorithm is able to distinguish ADHD from control with hold-out accuracy of 69.6% (over baseline 55.0% using personal characteristics and structural brain scan features when trained on the ADHD-200 dataset (769 participants in training set, 171 in test set. It is able to distinguish autism from control with hold-out accuracy of 65.0% (over baseline 51.6% using functional images with personal characteristic data when trained on the Autism Brain Imaging Data Exchange (ABIDE dataset (889 participants in training set, 222 in test set. These results outperform all previously presented methods on both datasets. To our knowledge, this is the first demonstration of a single automated learning process that can produce classifiers for distinguishing patients vs. controls from brain imaging data with above-chance accuracy on large datasets for two different psychiatric illnesses (ADHD and autism. Working toward clinical applications requires robustness against real-world conditions, including the substantial variability that often exists among data collected at different institutions. It is therefore important that our algorithm was successful with the large ADHD-200 and ABIDE datasets, which include data from hundreds of participants collected at multiple institutions. While the resulting classifiers are not yet clinically relevant, this work shows that there is a signal in

  1. Characteristics of magnetic resonance imaging with partial flip angle and gradient field echo

    International Nuclear Information System (INIS)

    Hamada, Tatsumi; Uto, Tatsurou; Okafuji, Tatsumasa; Ookusa, Akihiko; Oonishi, Takuya; Mabuchi, Nobuhisa; Fujii, Kouichi; Yoshioka, Hiroyasu; Ishida, Osamu

    1988-01-01

    Characteristics of a magnetic resonance (MR) imaging pulse sequence with short repetition time (Tr), short echo time (Te), partial flip angle and gradient field echo, at 0.5 T, were studied. A series of sagittal images of the cerebrospinal region was obtained with varied Tr, Te and flip angle, signal intensities were measured by means of a region of interest (ROI) function, and optimal parameters to achieve maximum tissue contrast were found. Of the parameters flip angle had the greatest effect on tissue contrast. Flip angles less than 20 or more than 60 degrees were necessary to discriminate between spinal cord and cerebrospinal fluid. So called MR myelography was obtained with the flip angle of 15 degrees. Opposed and inphase images were obtained at the Te levels of 21 and 28 ms, respectively. Likewise, a series of transverse images of the abdomen with short Tr, short Te and varied flip angles was obtained in a breath-holding interval, and signal intensities of ROIs were measured. Maximum intensities of the liver, the spleen and perirenal fat were obtained at the flip angles of 40, 30 and 60 degrees, respectively. Although maximum intensity was found at the flip angle of 30 degrees for both of the renal cortex and medulla, the maximum contrast between the two tissues was obtained at the flip angles of 50-60 degrees. The image contrast obtained by these pulse sequences was also theoretically predictable, and so it is thought possible that flip angle, Tr and Te are manipulated to yield a desired contrast. (author)

  2. Anatomic characteristics and natural history of renal artery aneurysms during longitudinal imaging surveillance.

    Science.gov (United States)

    Wayne, Erik J; Edwards, Matthew S; Stafford, Jeanette M; Hansen, Kimberley J; Corriere, Matthew A

    2014-08-01

    Renal artery aneurysms (RAAs) are uncommon, and rates of growth and rupture are unknown. Limited evidence therefore exists to guide clinical management of RAAs, particularly small aneurysms that are asymptomatic. To further characterize the natural history of RAAs, we studied anatomic characteristics and changes in diameter during imaging surveillance. Patients evaluated for native RAAs at a single institution during a 5-year period (July 2008 to July 2013) were identified and analyzed retrospectively. Patients with two or more cross-sectional imaging studies (computed tomography or magnetic resonance imaging) more than 1 month apart were included. Demographic and clinical data were collected from medical records, and anatomic data (including aneurysm diameter, calcification, and location) were obtained from electronic images. Changes in RAA diameters over time were evaluated by plots and Wilcoxon signed rank tests. Sixty-eight RAAs in 55 patients were analyzed. Median follow-up was 19.4 months (interquartile range, 11.2-49.0 months). Mean age at presentation was 61.8 ± 9.8 years, and 73% of patients were women. Hypertension was prevalent among 73% of patients. Multiple RAAs were present in 18% of patients, and 24% also had arterial aneurysms of other splanchnic or iliac vessels. The majority of RAAs were calcified and located at the main renal artery bifurcation. Mean initial aneurysm diameter was 16.0 ± 6.4 mm. Median annualized growth rate was 0.06 mm (interquartile range, -0.07 to 0.33 mm; P = .11). No RAA ruptures or acute symptoms occurred during surveillance, and 10.3% of RAAs were repaired electively. Risk of short-term RAA growth or rupture was low. These findings suggest that annual (or less frequent) imaging surveillance is safe in the majority of patients and do not support pre-emptive repair of asymptomatic, small-diameter RAAs. Copyright © 2014 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

  3. MALDI imaging mass spectrometry: discrimination of pathophysiological regions in traumatized skeletal muscle by characteristic peptide signatures.

    Science.gov (United States)

    Klein, Oliver; Strohschein, Kristin; Nebrich, Grit; Oetjen, Janina; Trede, Dennis; Thiele, Herbert; Alexandrov, Theodore; Giavalisco, Patrick; Duda, Georg N; von Roth, Philipp; Geissler, Sven; Klose, Joachim; Winkler, Tobias

    2014-10-01

    Due to formation of fibrosis and the loss of contractile muscle tissue, severe muscle injuries often result in insufficient healing marked by a significant reduction of muscle force and motor activity. Our previous studies demonstrated that the local transplantation of mesenchymal stromal cells into an injured skeletal muscle of the rat improves the functional outcome of the healing process. Since, due to the lack of sufficient markers, the accurate discrimination of pathophysiological regions in injured skeletal muscle is inadequate, underlying mechanisms of the beneficial effects of mesenchymal stromal cell transplantation on primary trauma and trauma adjacent muscle area remain elusive. For discrimination of these pathophysiological regions, formalin-fixed injured skeletal muscle tissue was analyzed by MALDI imaging MS. By using two computational evaluation strategies, a supervised approach (ClinProTools) and unsupervised segmentation (SCiLS Lab), characteristic m/z species could be assigned to primary trauma and trauma adjacent muscle regions. Using "bottom-up" MS for protein identification and validation of results by immunohistochemistry, we could identify two proteins, skeletal muscle alpha actin and carbonic anhydrase III, which discriminate between the secondary damage on adjacent tissue and the primary traumatized muscle area. Our results underscore the high potential of MALDI imaging MS to describe the spatial characteristics of pathophysiological changes in muscle. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Sustained attention is associated with right superior longitudinal fasciculus and superior parietal white matter microstructure in children

    DEFF Research Database (Denmark)

    Klarborg, Brith; Skak Madsen, Kathrine; Vestergaard, Martin

    2013-01-01

    Sustained attention develops during childhood and has been linked to the right fronto-parietal cortices in functional imaging studies; however, less is known about its relation to white matter (WM) characteristics. Here we investigated whether the microstructure of the WM underlying and connecting...... the right fronto-parietal cortices was associated with sustained attention performance in a group of 76 typically developing children aged 7-13 years. Sustained attention was assessed using a rapid visual information processing paradigm. The two behavioral measures of interest were the sensitivity index d......' and the coefficient of variation in reaction times (RT(CV) ). Diffusion-weighted imaging was performed. Mean fractional anisotropy (FA) was extracted from the WM underlying right dorsolateral prefrontal (DLPFC) and parietal cortex (PC), and the right superior longitudinal fasciculus (SLF), as well as equivalent...

  5. Superior facet syndrome

    International Nuclear Information System (INIS)

    Kubo, Yoshichika; Igarashi, Seishi; Koyama, Tsunemaro

    1985-01-01

    Sciatica caused by root entrapment in the lateral recess was named superior facet syndrome by Epstein in 1972. Few reports on this subject based on large numbers of cases have been documented to date. Of the patients with sciatica, 32 patients were diagnosed to have root entrapment at the lateral recess L 5 or/and S 1 lumbar spine. Out of 32 patients, 20 patients were operated on and the lateral entrapment was recognized in all of surgical cases. Neuroradiological findings, especially of metrizamide CT (met. CT), were documented in detail. Thirty two patients were classified in three types according to radiological findings. They were congenital or developmental, degenerative, and combined type, respectively, Fourteen cases belonged to the congenital type, 13 to the degenerative and 5 to the combined type. Each group had the mean ages of 23.4, 53.8, and 36.8 years old, respectively. Of 32 cases the entrapment occured in 47 L 5 roots and 11 S 1 roots. There was no remarkable laterality. In operation the unroofing of the lateral recess were done and the sciatica subsided postoperatively in all of surgical cases. Met. CT revealed extreme medial protrusion of the superior articular joint in 18 of 24 cases(75%) and none filling of the root in the lateral recess in 21 of 24 cases (87.5%). In the degenerative type, met. CT showed some degenerative changes that were hypertrophy or deformity of the articular joints and spur formation of the vertebral body. In contrast to met. CT, metrizamide myelography revealed only slight changes, which were poor filling of the root before it turned out the pedicle of lateral compression of the root. In plain films or lumbar spine articular joints at Lsub(4/5) were formed in coronal plane in 69% of cases of the L 5 root entrapment. Met. CT using ReView technique was of great diagnostic value in superior facet syndrome. (author)

  6. [Analysis of clinical and imaging characteristics of infectious sacroiliac arthritis and review of literatures].

    Science.gov (United States)

    Wang, Gang; Wang, Yanyan; Zhu, Jian; Jin, Jingyu; Zhao, Zheng; Zhang, Jianglin; Huang, Feng

    2015-05-01

    To study the clinical and imaging characteristics of patients with infectious sacroiliac arthritis. Twenty-one patients diagnosed with infectious sacroiliac arthritis were analyzed retrospectively between 2000 and 2014. The chief complaint was pain in hip and lumbosacral area. Their clinical features, laboratory tests and pathological examination results as well as CT/MRI/PET-CT images were evaluated. There were nine males and thirteen females eighteen (85.7%) patients had unilateral sacroiliac joint involvement. Among these patients, three were diagnosed with brucellosis sacroiliac arthritis (BSI), eight patients with tuberculosis sacroiliac arthritis (TSI), and ten patients with non-brucellosis and non-tuberculosis infectious sacroiliac arthritis (ISI). For those patients with non-brucellosis and non-tuberculosis infectious sacroiliac arthritis, white blood cell count, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were dramatically increased. Twelve patients were diagnosed pathologically including 6 ISI, 2 BSI and 4 TSI. Twelve patients and seventeen patients were scanned by CT and MRI respectively. Two patients undertook PET-CT examination. Antibiotic therapy showed significant therapeutic effects in all patients. Infectious sacroiliac arthritis patients with hip or lumbosacral pain as the chief complaint can be easily misdiagnosed as spondyloarthritis. Comprehensive analysis of clinical features, imaging and laboratory findings is essential for accurate diagnosis.

  7. Specific image characteristics influence attitudes about chimpanzee conservation and use as pets.

    Directory of Open Access Journals (Sweden)

    Stephen R Ross

    Full Text Available Chimpanzees are endangered in their native Africa but in the United States, they are housed not only in zoos and research centers but owned privately as pets and performers. In 2008, survey data revealed that the public is less likely to think that chimpanzees are endangered compared to other great apes, and that this is likely the result of media misportrayals in movies, television and advertisements. Here, we use an experimental survey paradigm with composite images of chimpanzees to determine the effects of specific image characteristics. We found that those viewing a photograph of a chimpanzee with a human standing nearby were 35.5% more likely to consider wild populations to be stable/healthy compared to those seeing the exact same picture without a human. Likewise, the presence of a human in the photograph increases the likelihood that they consider chimpanzees as appealing as a pet. We also found that respondents seeing images in which chimpanzees are shown in typically human settings (such as an office space were more likely to perceive wild populations as being stable and healthy compared to those seeing chimpanzees in other contexts. These findings shed light on the way that media portrayals of chimpanzees influence public attitudes about this important and endangered species.

  8. Specific image characteristics influence attitudes about chimpanzee conservation and use as pets.

    Science.gov (United States)

    Ross, Stephen R; Vreeman, Vivian M; Lonsdorf, Elizabeth V

    2011-01-01

    Chimpanzees are endangered in their native Africa but in the United States, they are housed not only in zoos and research centers but owned privately as pets and performers. In 2008, survey data revealed that the public is less likely to think that chimpanzees are endangered compared to other great apes, and that this is likely the result of media misportrayals in movies, television and advertisements. Here, we use an experimental survey paradigm with composite images of chimpanzees to determine the effects of specific image characteristics. We found that those viewing a photograph of a chimpanzee with a human standing nearby were 35.5% more likely to consider wild populations to be stable/healthy compared to those seeing the exact same picture without a human. Likewise, the presence of a human in the photograph increases the likelihood that they consider chimpanzees as appealing as a pet. We also found that respondents seeing images in which chimpanzees are shown in typically human settings (such as an office space) were more likely to perceive wild populations as being stable and healthy compared to those seeing chimpanzees in other contexts. These findings shed light on the way that media portrayals of chimpanzees influence public attitudes about this important and endangered species.

  9. Design of a receiver operating characteristic (ROC) study of 10:1 lossy image compression

    Science.gov (United States)

    Collins, Cary A.; Lane, David; Frank, Mark S.; Hardy, Michael E.; Haynor, David R.; Smith, Donald V.; Parker, James E.; Bender, Gregory N.; Kim, Yongmin

    1994-04-01

    The digital archiving system at Madigan Army Medical Center (MAMC) uses a 10:1 lossy data compression algorithm for most forms of computed radiography. A systematic study on the potential effect of lossy image compression on patient care has been initiated with a series of studies focused on specific diagnostic tasks. The studies are based upon the receiver operating characteristic (ROC) method of analysis for diagnostic systems. The null hypothesis is that observer performance with approximately 10:1 compressed and decompressed images is not different from using original, uncompressed images for detecting subtle pathologic findings seen on computed radiographs of bone, chest, or abdomen, when viewed on a high-resolution monitor. Our design involves collecting cases from eight pathologic categories. Truth is determined by committee using confirmatory studies performed during routine clinical practice whenever possible. Software has been developed to aid in case collection and to allow reading of the cases for the study using stand-alone Siemens Litebox workstations. Data analysis uses two methods, ROC analysis and free-response ROC (FROC) methods. This study will be one of the largest ROC/FROC studies of its kind and could benefit clinical radiology practice using PACS technology. The study design and results from a pilot FROC study are presented.

  10. Association Between Imaging Characteristics and Different Molecular Subtypes of Breast Cancer.

    Science.gov (United States)

    Wu, Mingxiang; Ma, Jie

    2017-04-01

    Breast cancer can be divided into four major molecular subtypes based on the expression of hormone receptor (estrogen receptor and progesterone receptor), human epidermal growth factor receptor 2, HER2 status, and molecular proliferation rate (Ki67). In this study, we sought to investigate the association between breast cancer subtype and radiological findings in the Chinese population. Medical records of 300 consecutive invasive breast cancer patients were reviewed from the database: the Breast Imaging Reporting and Data System. The imaging characteristics of the lesions were evaluated. The molecular subtypes of breast cancer were classified into four types: luminal A, luminal B, HER2 overexpressed (HER2), and basal-like breast cancer (BLBC). Univariate and multivariate logistic regression analyses were performed to assess the association between the subtype (dependent variable) and mammography or 15 magnetic resonance imaging (MRI) indicators (independent variables). Luminal A and B subtypes were commonly associated with "clustered calcification distribution," "nipple invasion," or "skin invasion" (P cancers showed association with persistent enhancement in the delayed phase on MRI and "clustered calcification distribution" on mammography (P breast tumor, which are potentially useful tools in the diagnosis and subtyping of breast cancer. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  11. Hydatid disease of the Central Nervous System: imaging characteristics and general features

    International Nuclear Information System (INIS)

    Abbassioun, K.; Amirjamshidi, A.; Sabouri Deylamie, M.

    2003-01-01

    Background: Hydatid disease primarily affects the liver and typically demonstrates characteristic imaging findings. Secondary involvement due to hematogenous dissemination may be seen in almost any locations, e.g., lung, kidney, spleen, bone and central nervous system. Objectives: To review the different aspects of hydatidosis of the central nervous system briefly and discuss the pathognomonic features and rare varieties of radiological findings useful in preoperative diagnosis of the disease in the human central nervous system. Materials and Methods: In a retrospective study, the records of almost 100 cases of central nervous system hydatidosis were analyzed . The available images were reviewed by independent observers, either a radiologist or a neurosurgeon, and reported separately. Results: In skull x-ray films, nonspecific changes denoted increased intracranial pressure, skull asymmetry and curvilinear calcification in rare instances. Computed tomography and magnetic resonance imaging demonstrated the round or oval, well-defined cystic mass with an attenuation or signal intensity similar to that of cerebrospinal fluid, with no associated perifocal edema, and no contrast enhancement as the pathognomonic findings of brain hydatidosis. Similar findings were detected in hydatid cysts involving the orbit, spinal column and spinal cord with some variations. Such findings as mild perifocal edema, non homogenous contrast enhancement, non-uniform shapes, calcification and multiplicity or septations have been the atypical radiological findings. Conclusion: In endemic areas, familiarity with typical and atypical radiological manifestations of hydatid disease of the central nervous system, will be helpful in making prompt and correct preoperative diagnosis leading to a better surgical outcome

  12. Investigation of physical image characteristics and phenomenon of edge enhancement by phase contrast using equipment typical for mammography

    International Nuclear Information System (INIS)

    Yamazaki, Asumi; Ichikawa, Katsuhiro; Kodera, Yoshie

    2008-01-01

    A technique called phase contrast mammography (PCM) has only recently been applied in clinical examination. In this application, PCM images are acquired at a 1.75x magnification using an x-ray tube for clinical use, and then reduced to the real size of the object by image processing. The images showed enhanced object edges; reportedly, this enhancement occurred because of the refraction of x rays through a cylindrical object. The authors measured the physical image characteristics of PCM to compare the image characteristics of PCM with those of conventional mammography. More specifically, they measured the object-edge-response characteristics and the noise characteristics in the spatial frequency domain. The results revealed that the edge-response characteristics of PCM outperformed those of conventional mammography. In addition, the characteristics changed with the object-placement conditions and the object shapes. The noise characteristics of PCM were better than those of conventional mammography. Subsequently, to verify why object edges were enhanced in PCM images, the authors simulated image profiles that would be obtained if the x rays were refracted and totally reflected by using not only a cylindrical substance but also a planar substance as the object. So, they confirmed that the object edges in PCM images were enhanced because x rays were refracted irrespective of the object shapes. Further, they found that the edge enhancements depended on the object shapes and positions. It was also proposed that the larger magnification than 1.75 in the commercialized system might be more suitable for PCM. Finally, the authors investigated phase-contrast effects to breast tissues by the simulation and demonstrated that PCM would be helpful in the diagnoses of mammography.

  13. Performance characteristics of magnetic resonance imaging without contrast agents or sedation in pediatric appendicitis

    Energy Technology Data Exchange (ETDEWEB)

    Didier, Ryne A.; Hopkins, Katharine L.; Coakley, Fergus V.; Foster, Bryan R. [Oregon Health and Science University, Department of Diagnostic Radiology, Portland, OR (United States); Krishnaswami, Sanjay [Oregon Health and Science University, Department of Surgery, Portland, OR (United States); Oregon Health and Science University, Department of Pediatrics, Portland, OR (United States); Spiro, David M. [Oregon Health and Science University, Department of Pediatrics, Portland, OR (United States)

    2017-09-15

    Magnetic resonance imaging (MRI) has emerged as a promising modality for evaluating pediatric appendicitis. However optimal imaging protocols, including roles of contrast agents and sedation, have not been established and diagnostic criteria have not been fully evaluated. To investigate performance characteristics of rapid MRI without contrast agents or sedation in the diagnosis of pediatric appendicitis. We included patients ages 4-18 years with suspicion of appendicitis who underwent rapid MRI between October 2013 and March 2015 without contrast agent or sedation. After two-radiologist review, we determined performance characteristics of individual diagnostic criteria and aggregate diagnostic criteria by comparing MRI results to clinical outcomes. We used receiver operating characteristic (ROC) curves to determine cut-points for appendiceal diameter and wall thickness for optimization of predictive power, and we calculated area under the curve (AUC) as a measure of test accuracy. Ninety-eight MRI examinations were performed in 97 subjects. Overall, MRI had a 94% sensitivity, 95% specificity, 91% positive predictive value and 97% negative predictive value. Optimal cut-points for appendiceal diameter and wall thickness were ≥7 mm and ≥2 mm, respectively. Independently, those cut-points produced sensitivities of 91% and 84% and specificities of 84% and 43%. Presence of intraluminal fluid (30/33) or localized periappendiceal fluid (32/33) showed a significant association with acute appendicitis (P<0.01), with sensitivities of 91% and 97% and specificities of 60% and 50%. For examinations in which the appendix was not identified by one or both reviewers (23/98), the clinical outcome was negative. Rapid MRI without contrast agents or sedation is accurate for diagnosis of pediatric appendicitis when multiple diagnostic criteria are considered in aggregate. Individual diagnostic criteria including optimized cut-points of ≥7 mm for diameter and ≥2 mm for wall

  14. Performance characteristics of magnetic resonance imaging without contrast agents or sedation in pediatric appendicitis

    International Nuclear Information System (INIS)

    Didier, Ryne A.; Hopkins, Katharine L.; Coakley, Fergus V.; Foster, Bryan R.; Krishnaswami, Sanjay; Spiro, David M.

    2017-01-01

    Magnetic resonance imaging (MRI) has emerged as a promising modality for evaluating pediatric appendicitis. However optimal imaging protocols, including roles of contrast agents and sedation, have not been established and diagnostic criteria have not been fully evaluated. To investigate performance characteristics of rapid MRI without contrast agents or sedation in the diagnosis of pediatric appendicitis. We included patients ages 4-18 years with suspicion of appendicitis who underwent rapid MRI between October 2013 and March 2015 without contrast agent or sedation. After two-radiologist review, we determined performance characteristics of individual diagnostic criteria and aggregate diagnostic criteria by comparing MRI results to clinical outcomes. We used receiver operating characteristic (ROC) curves to determine cut-points for appendiceal diameter and wall thickness for optimization of predictive power, and we calculated area under the curve (AUC) as a measure of test accuracy. Ninety-eight MRI examinations were performed in 97 subjects. Overall, MRI had a 94% sensitivity, 95% specificity, 91% positive predictive value and 97% negative predictive value. Optimal cut-points for appendiceal diameter and wall thickness were ≥7 mm and ≥2 mm, respectively. Independently, those cut-points produced sensitivities of 91% and 84% and specificities of 84% and 43%. Presence of intraluminal fluid (30/33) or localized periappendiceal fluid (32/33) showed a significant association with acute appendicitis (P<0.01), with sensitivities of 91% and 97% and specificities of 60% and 50%. For examinations in which the appendix was not identified by one or both reviewers (23/98), the clinical outcome was negative. Rapid MRI without contrast agents or sedation is accurate for diagnosis of pediatric appendicitis when multiple diagnostic criteria are considered in aggregate. Individual diagnostic criteria including optimized cut-points of ≥7 mm for diameter and ≥2 mm for wall

  15. Performance characteristics of magnetic resonance imaging without contrast agents or sedation in pediatric appendicitis.

    Science.gov (United States)

    Didier, Ryne A; Hopkins, Katharine L; Coakley, Fergus V; Krishnaswami, Sanjay; Spiro, David M; Foster, Bryan R

    2017-09-01

    Magnetic resonance imaging (MRI) has emerged as a promising modality for evaluating pediatric appendicitis. However optimal imaging protocols, including roles of contrast agents and sedation, have not been established and diagnostic criteria have not been fully evaluated. To investigate performance characteristics of rapid MRI without contrast agents or sedation in the diagnosis of pediatric appendicitis. We included patients ages 4-18 years with suspicion of appendicitis who underwent rapid MRI between October 2013 and March 2015 without contrast agent or sedation. After two-radiologist review, we determined performance characteristics of individual diagnostic criteria and aggregate diagnostic criteria by comparing MRI results to clinical outcomes. We used receiver operating characteristic (ROC) curves to determine cut-points for appendiceal diameter and wall thickness for optimization of predictive power, and we calculated area under the curve (AUC) as a measure of test accuracy. Ninety-eight MRI examinations were performed in 97 subjects. Overall, MRI had a 94% sensitivity, 95% specificity, 91% positive predictive value and 97% negative predictive value. Optimal cut-points for appendiceal diameter and wall thickness were ≥7 mm and ≥2 mm, respectively. Independently, those cut-points produced sensitivities of 91% and 84% and specificities of 84% and 43%. Presence of intraluminal fluid (30/33) or localized periappendiceal fluid (32/33) showed a significant association with acute appendicitis (Pappendicitis when multiple diagnostic criteria are considered in aggregate. Individual diagnostic criteria including optimized cut-points of ≥7 mm for diameter and ≥2 mm for wall thickness demonstrate high sensitivities but relatively low specificities. Nonvisualization of the appendix favors a negative diagnosis.

  16. Language Development and Brain Magnetic Resonance Imaging Characteristics in Preschool Children With Cerebral Palsy.

    Science.gov (United States)

    Choi, Ja Young; Choi, Yoon Seong; Park, Eun Sook

    2017-05-24

    The purpose of this study was to investigate characteristics of language development in relation to brain magnetic resonance imaging (MRI) characteristics and the other contributing factors to language development in children with cerebral palsy (CP). The study included 172 children with CP who underwent brain MRI and language assessments between 3 and 7 years of age. The MRI characteristics were categorized as normal, malformation, periventricular white matter lesion (PVWL), deep gray matter lesion, focal infarct, cortical/subcortical lesion, and others. Neurodevelopmental outcomes such as ambulatory status, manual ability, cognitive function, and accompanying impairments were assessed. Both receptive and expressive language development quotients (DQs) were significantly related to PVWL or deep gray matter lesion severity. In multivariable analysis, only cognitive function was significantly related to receptive language development, whereas ambulatory status and cognitive function were significantly associated with expressive language development. More than one third of the children had a language developmental discrepancy between receptive and expressive DQs. Children with cortical/subcortical lesions were at high risk for this discrepancy. Cognitive function is a key factor for both receptive and expressive language development. In children with PVWL or deep gray matter lesion, lesion severity seems to be useful to predict language development.

  17. Gangliogliomas: characteristic imaging findings and role in the temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Y; Yagishita, A [Tokyo Metropolitan Neurological Hospital, Department of Neuroradiology, Tokyo (Japan)

    2008-10-15

    Ganglioglioma is an uncommon neoplasm of the central nervous system, most frequently seen in the temporal lobe, and usually associated with medically refractory epilepsy in children and young adults. Few reports have considered ganglioglioma-associated epileptogenicity arising in the temporal lobe. The purpose of our study was to define the imaging features of ganglioglioma in the temporal lobe and their relation to the seizure foci revealed by electrocorticograms. We reviewed 24 patients with pathologically confirmed ganglioglioma in the temporal lobe. Computed tomography (CT) images showed gangliogliomas to be isodense (91.7%), and on T1-weighted images (T1-WI) most gangliogliomas (79.2%) were isointense to the gray matter. A cystic lesion was seen in 14 of 24 of the gangliogliomas (58.3%). Mass effects were not seen in any of the ten tumors without cystic components. One patient showed tumor recurrence. Dual pathology was seen in two cases (8.3%). In 23 cases, epileptogenicity was confirmed in the tumors by intraoperative electrocorticogram. The remaining case had no epileptogenicity. A tumor presenting isointensity to gray matter on T1-WI without mass effects in the medial temporal lobe in a young patient with temporal lobe epilepsy (TLE) might be the characteristic imaging of temporal lobe ganglioglioma. However, such tumors are not always associated with epileptogenicity, even if a ganglioglioma is found in a patient with TLE. The seizure foci may be contralateral to the ganglioglioma. Therefore, we need to investigate the hippocampus, white matter abnormalities of the ipsilateral and contralateral anterior temporal lobe, and other focal lesions closely. (orig.)

  18. Gangliogliomas: characteristic imaging findings and role in the temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Adachi, Y.; Yagishita, A.

    2008-01-01

    Ganglioglioma is an uncommon neoplasm of the central nervous system, most frequently seen in the temporal lobe, and usually associated with medically refractory epilepsy in children and young adults. Few reports have considered ganglioglioma-associated epileptogenicity arising in the temporal lobe. The purpose of our study was to define the imaging features of ganglioglioma in the temporal lobe and their relation to the seizure foci revealed by electrocorticograms. We reviewed 24 patients with pathologically confirmed ganglioglioma in the temporal lobe. Computed tomography (CT) images showed gangliogliomas to be isodense (91.7%), and on T1-weighted images (T1-WI) most gangliogliomas (79.2%) were isointense to the gray matter. A cystic lesion was seen in 14 of 24 of the gangliogliomas (58.3%). Mass effects were not seen in any of the ten tumors without cystic components. One patient showed tumor recurrence. Dual pathology was seen in two cases (8.3%). In 23 cases, epileptogenicity was confirmed in the tumors by intraoperative electrocorticogram. The remaining case had no epileptogenicity. A tumor presenting isointensity to gray matter on T1-WI without mass effects in the medial temporal lobe in a young patient with temporal lobe epilepsy (TLE) might be the characteristic imaging of temporal lobe ganglioglioma. However, such tumors are not always associated with epileptogenicity, even if a ganglioglioma is found in a patient with TLE. The seizure foci may be contralateral to the ganglioglioma. Therefore, we need to investigate the hippocampus, white matter abnormalities of the ipsilateral and contralateral anterior temporal lobe, and other focal lesions closely. (orig.)

  19. Fundamental imaging characteristics of a slot-scan digital chest radiographic system

    International Nuclear Information System (INIS)

    Samei, Ehsan; Saunders, Robert S.; Lo, Joseph Y.; Dobbins, James T. III; Jesneck, Jonathan L.; Floyd, Carey E.; Ravin, Carl E.

    2004-01-01

    Our purpose in this study was to evaluate the fundamental image quality characteristics of a new slot-scan digital chest radiography system (ThoraScan, Delft Imaging Systems/Nucletron, Veenendaal, The Netherlands). The linearity of the system was measured over a wide exposure range at 90, 117, and 140 kVp with added Al filtration. System uniformity and reproducibility were established with an analysis of images from repeated exposures. The modulation transfer function (MTF) was evaluated using an established edge method. The noise power spectrum (NPS) and the detective quantum efficiency (DQE) of the system were evaluated at the three kilo-voltages over a range of exposures. Scatter fraction (SF) measurements were made using a posterior beam stop method and a geometrical chest phantom. The system demonstrated excellent linearity, but some structured nonuniformities. The 0.1 MTF values occurred between 3.3-3.5 mm -1 . The DQE(0.15) and DQE(2.5) were 0.21 and 0.07 at 90 kVp, 0.18 and 0.05 at 117 kVp, and 0.16 and 0.03 at 140 kVp, respectively. The system exhibited remarkably lower SFs compared to conventional full-field systems with anti-scatter grid, measuring 0.13 in the lungs and 0.43 in the mediastinum. The findings indicated that the slot-scan design provides marked scatter reduction leading to high effective DQE (DQE eff ) of the system and reduced patient dose required to achieve high image quality

  20. Imaging characteristics associated with clinical outcomes in posterior reversible encephalopathy syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Schweitzer, Andrew D.; Nemade, Ajay [Weill Cornell Medicine, Department of Radiology, New York, NY (United States); Parikh, Neal S.; Navi, Babak B. [Weill Cornell Medicine, Department of Neurology, New York, NY (United States); Weill Cornell Medicine, Clinical and Translational Neuroscience Unit, Feil Family Brain and Mind Research Institute, New York, NY (United States); Askin, Gulce [Weill Cornell Medicine, Department of Healthcare Policy and Research, Division of Biostatistics and Epidemiology, New York, NY (United States); Lyo, John; Karimi, Sasan; Knobel, Anna; Young, Robert J. [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Gupta, Ajay [Weill Cornell Medicine, Department of Radiology, New York, NY (United States); Weill Cornell Medicine, Clinical and Translational Neuroscience Unit, Feil Family Brain and Mind Research Institute, New York, NY (United States)

    2017-04-15

    Posterior reversible encephalopathy syndrome (PRES) is a disorder of cerebrovascular autoregulation that can result in brain edema, hemorrhage, and infarction. We sought to investigate whether certain imaging characteristics in PRES are associated with clinically significant patient outcomes. We retrospectively reviewed all cases of PRES occurring between 2008 and 2014 at two major academic medical centers. Demographic, clinical, and radiographic data were collected. We analyzed imaging studies for vasogenic edema, hemorrhage, and diffusion restriction. We performed univariate analysis and stepwise logistic regression to assess the association between our radiologic findings of interest and clinical outcomes as defined by hospital discharge disposition and modified Rankin scale (mRS) at time of discharge. We identified 99 cases of PRES in 96 patients. The median age was 55 years (IQR 30-65) and 74% were women. In 99 cases, 60% of patients had active cancer, 19% had history of bone marrow or organ transplantation, 14% had autoimmune disease, and 8% were peripartum. Imaging at clinical presentation showed extensive vasogenic edema in 39%, hemorrhage in 36%, hemorrhage with mass effect in 7%, and restricted diffusion in 16%. In our final logistic regression models, the presence of extensive vasogenic edema, hemorrhage with mass effect, or diffusion restriction was associated with worse clinical outcome as defined by both discharge disposition (OR = 4.3; 95% CI: 1.4-36.3; p = 0.047) and mRS (OR = 3.6; 95% CI: 1.2-10.7; p = 0.019). Extensive vasogenic edema, hemorrhage, and restricted diffusion on initial imaging in PRES are associated with worse clinical outcomes. (orig.)

  1. Cardiovascular magnetic resonance imaging (CMR) reveals characteristic pattern of myocardial damage in patients with mitochondrial myopathy.

    Science.gov (United States)

    Yilmaz, Ali; Gdynia, Hans-Jürgen; Ponfick, Matthias; Rösch, Sabine; Lindner, Alfred; Ludolph, Albert C; Sechtem, Udo

    2012-04-01

    Mitochondrial myopathy comprises various clinical subforms of neuromuscular disorders that are characterised by impaired mitochondrial energy metabolism due to dysfunction of the mitochondrial respiratory chain. No comprehensive and targeted cardiovascular magnetic resonance (CMR) studies have been performed so far in patients with mitochondrial disorders. The present study aimed at characterising cardiac disease manifestations in patients with mitochondrial myopathy and elucidating the in vivo cardiac damage pattern of patients with different subforms of mitochondrial disease by CMR studies. In a prospective study, 37 patients with mitochondrial myopathy underwent comprehensive neurological and cardiac evaluations including physical examination, resting ECG and CMR. The CMR studies comprised cine-CMR, T2-weighted "edema" imaging and T1-weighted late-gadolinium-enhancement (LGE) imaging. Various patterns and degrees of skeletal myopathy were present in the participants of this study, whereas clinical symptoms such as chest pain symptoms (in eight (22%) patients) and various degrees of dyspnea (in 16 (43%) patients) were less frequent. Pathological ECG findings were documented in eight (22%) patients. T2-weighted "edema" imaging was positive in one (3%) patient with MELAS (mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes) only. LGE imaging demonstrated the presence of non-ischemic LGE in 12 (32%) patients: 10 out of 24 (42%) patients with CPEO (chronic progressive external ophthalmoplegia) or KSS (Kearns-Sayre syndrome) and 2 of 3 (67%) patients with MELAS were LGE positive. All 10 LGE-positive patients with CPEO or KSS demonstrated a potentially typical pattern of diffuse intramural LGE in the left-ventricular (LV) inferolateral segments. Cardiac involvement is a frequent finding in patients with mitochondrial myopathy. A potentially characteristic pattern of diffuse intramural LGE in the LV inferolateral segments was identified in

  2. Imaging characteristics associated with clinical outcomes in posterior reversible encephalopathy syndrome

    International Nuclear Information System (INIS)

    Schweitzer, Andrew D.; Nemade, Ajay; Parikh, Neal S.; Navi, Babak B.; Askin, Gulce; Lyo, John; Karimi, Sasan; Knobel, Anna; Young, Robert J.; Gupta, Ajay

    2017-01-01

    Posterior reversible encephalopathy syndrome (PRES) is a disorder of cerebrovascular autoregulation that can result in brain edema, hemorrhage, and infarction. We sought to investigate whether certain imaging characteristics in PRES are associated with clinically significant patient outcomes. We retrospectively reviewed all cases of PRES occurring between 2008 and 2014 at two major academic medical centers. Demographic, clinical, and radiographic data were collected. We analyzed imaging studies for vasogenic edema, hemorrhage, and diffusion restriction. We performed univariate analysis and stepwise logistic regression to assess the association between our radiologic findings of interest and clinical outcomes as defined by hospital discharge disposition and modified Rankin scale (mRS) at time of discharge. We identified 99 cases of PRES in 96 patients. The median age was 55 years (IQR 30-65) and 74% were women. In 99 cases, 60% of patients had active cancer, 19% had history of bone marrow or organ transplantation, 14% had autoimmune disease, and 8% were peripartum. Imaging at clinical presentation showed extensive vasogenic edema in 39%, hemorrhage in 36%, hemorrhage with mass effect in 7%, and restricted diffusion in 16%. In our final logistic regression models, the presence of extensive vasogenic edema, hemorrhage with mass effect, or diffusion restriction was associated with worse clinical outcome as defined by both discharge disposition (OR = 4.3; 95% CI: 1.4-36.3; p = 0.047) and mRS (OR = 3.6; 95% CI: 1.2-10.7; p = 0.019). Extensive vasogenic edema, hemorrhage, and restricted diffusion on initial imaging in PRES are associated with worse clinical outcomes. (orig.)

  3. MR and CT imaging characteristics and ablation zone volumetry of locally advanced pancreatic cancer treated with irreversible electroporation

    Energy Technology Data Exchange (ETDEWEB)

    Vroomen, Laurien G.P.H.; Scheffer, Hester J.; Melenhorst, Marleen C.A.M.; Jong, Marcus C. de; Bergh, Janneke E. van den; Kuijk, Cornelis van; Meijerink, Martijn R. [VU University Medical Center, Department of Radiology and Nuclear Medicine, Amsterdam (Netherlands); Delft, Foke van [VU University Medical Center, Department of Gastroenterology and Hepatology, Amsterdam (Netherlands); Kazemier, Geert [VU University Medical Center, Department of Surgery, Amsterdam (Netherlands)

    2017-06-15

    To assess specific imaging characteristics after irreversible electroporation (IRE) for locally advanced pancreatic carcinoma (LAPC) with contrast-enhanced (ce)MRI and ceCT, and to explore the correlation of these characteristics with the development of recurrence. Qualitative and quantitative analyses of imaging data were performed on 25 patients treated with percutaneous IRE for LAPC. Imaging characteristics of the ablation zone on ceCT and ceMRI were assessed over a 6-month follow-up period. Contrast ratio scores between pre- and post-treatment were compared. To detect early imaging markers for treatment failure, attenuation characteristics at 6 weeks were linked to the area of recurrence within 6 months. Post-IRE, diffusion-weighted imaging (DWI)-b800 signal intensities decreased in all cases (p < 0.05). Both ceMRI and ceCT revealed absent or decreased contrast enhancement, with a hyperintense rim on ceMRI. Ablation zone volume increase was noted on both modalities in the first 6 weeks, followed by a decrease (p < 0.05). In the patients developing tumour recurrence (5/25), a focal DWI-b800 hyperintense spot at 6 weeks predated unequivocal recurrence on CT. The most remarkable signal alterations after pancreatic IRE were shown by DWI-b800 and ceMRI. These early imaging characteristics may be useful to establish technical success and predict treatment outcome. (orig.)

  4. An investigation of performance characteristics of a pixellated room-temperature semiconductor detector for medical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Guerra, P; Santos, A [Centro de Investigacion Biomedica de Bioningenieria, Biomateriales y Nanomedicina, CEEI-Modulo 3, C/ Maria de Luna, 11, 50018 Zaragoza (United States); Darambara, D G, E-mail: pguerra@ciber-bbn.e [Joint Department of Physics, Royal Marsden NHS Foundation Trust and Institute of Cancer Research, Fulham Road, London SW3 6JJ (United Kingdom)

    2009-09-07

    The operation of any semiconductor detector depends on the movement of the charge carriers, which are created within the material when radiation passes through, as a result of energy deposition. The carrier movement in the bulk semiconductor induces charges on the metal electrodes, and therefore a current on the electrodes and the external circuit. The induced charge strongly depends on the material transport parameters as well as the geometrical dimensions of a pixellated semiconductor detector. This work focuses on the performance optimization in terms of energy resolution, detection efficiency and intrinsic spatial resolution of a room-temperature semiconductor pixellated detector based on CdTe/CdZnTe. It analyses and inter-relates these performance figures for various dimensions of CdTe and CdZnTe detectors and for an energy range spanning from x-ray (25 keV) to PET (511 keV) imaging. Monte Carlo simulations, which integrate a detailed and accurate noise model, are carried out to investigate several CdTe/CdZnTe configurations and to determine possible design specifications. Under the considered conditions, the simulations demonstrate the superiority of the CdZnTe over the CdTe in terms of energy resolution and sensitivity in the photopeak. Further, according to the results, the spatial resolution is maximized at high energies and the energy resolution at low energies, while a reasonable detection efficiency is achieved at high energies, with a 1 x 1 x 6 mm{sup 3} CdZnTe pixellated detector.

  5. An investigation of performance characteristics of a pixellated room-temperature semiconductor detector for medical imaging

    International Nuclear Information System (INIS)

    Guerra, P; Santos, A; Darambara, D G

    2009-01-01

    The operation of any semiconductor detector depends on the movement of the charge carriers, which are created within the material when radiation passes through, as a result of energy deposition. The carrier movement in the bulk semiconductor induces charges on the metal electrodes, and therefore a current on the electrodes and the external circuit. The induced charge strongly depends on the material transport parameters as well as the geometrical dimensions of a pixellated semiconductor detector. This work focuses on the performance optimization in terms of energy resolution, detection efficiency and intrinsic spatial resolution of a room-temperature semiconductor pixellated detector based on CdTe/CdZnTe. It analyses and inter-relates these performance figures for various dimensions of CdTe and CdZnTe detectors and for an energy range spanning from x-ray (25 keV) to PET (511 keV) imaging. Monte Carlo simulations, which integrate a detailed and accurate noise model, are carried out to investigate several CdTe/CdZnTe configurations and to determine possible design specifications. Under the considered conditions, the simulations demonstrate the superiority of the CdZnTe over the CdTe in terms of energy resolution and sensitivity in the photopeak. Further, according to the results, the spatial resolution is maximized at high energies and the energy resolution at low energies, while a reasonable detection efficiency is achieved at high energies, with a 1 x 1 x 6 mm 3 CdZnTe pixellated detector.

  6. Nonresearch Industry Payments to Radiologists: Characteristics and Associations With Regional Medical Imaging Utilization.

    Science.gov (United States)

    Kokabi, Nima; Junn, Jacqueline C; Xing, Minzhi; Hemingway, Jennifer; Hughes, Danny R; Duszak, Richard

    2017-03-01

    To evaluate characteristics of nonresearch industry payments to radiologists and associations with regional diagnostic imaging utilization. Using 2014 CMS Open Payment data, all disclosed nonresearch-related industry payments to radiologists were identified. Health Resources and Services Administration Area Health Resources Files were used to identify actual and population-weighted numbers of radiologists by state. Utilizing the 5% random beneficiary sample CMS Research Identifiable Files from 2014, average Medicare imaging spending per beneficiary in each state was calculated. Average frequency and dollar amounts of nonresearch nonroyalty payments to radiologists were calculated at the state level. Using the Pearson correlation coefficient, the relationship between frequency and amounts of nonresearch payments to radiologists versus per-beneficiary Medicare imaging spending was evaluated at the state level. Overall, 2,008 radiologists (1,670 diagnostic, 338 interventional) received nonresearch nonroyalty payments from industry, representing 5.2% of all 38,857 radiologists nationwide. A total of 4,975 individual transfers translated to 2.5 ± 1.3 discrete payments per receiving radiologist with a mean of $432 ± $1,976 (median $26; range $1-$34,050). Food and beverage expenses constituted the vast majority of disclosed transfers (4,111; 83%), followed by travel and lodging (444; 9%), consulting fees (279; 6%), and educational expenses (51; 1%). Considerable geographic variation in payments was observed, ranging from 0% of radiologists in Vermont to 12.9% in the District of Columbia. No correlation was identified between average per-beneficiary Medicare imaging spending and the proportion of nonresearch-funded radiologists in each state (r = 0.06). Similarly, no correlation was identified between average per-beneficiary Medicare imaging spending and the average nonresearch transfer amount to radiologists in each state (r = -0.08). In 2014, only a small minority of

  7. Information Superiority through Data Warehousing

    National Research Council Canada - National Science Library

    Warner, Neil

    2001-01-01

    .... A precursor to a knowledge edge is Information Superiority. Within most current Command Support Systems minimal integration and fusion of data is undertaken to provide the basis of information superiority...

  8. Usefulness of multidetector-row CT (MDCT) for the diagnosis of non-occlusive mesenteric ischemia (NOMI): Assessment of morphology and diameter of the superior mesenteric artery (SMA) on multi-planar reconstructed (MPR) images

    International Nuclear Information System (INIS)

    Woodhams, Reiko; Nishimaki, Hiroshi; Fujii, Kaoru; Kakita, Satoko; Hayakawa, Kazushige

    2010-01-01

    Objective: The purpose of this study was to assess the efficacy of multidetector-row CT (MDCT) for the diagnosis of non-occlusive mesenteric ischemia (NOMI) by analyzing morphology and diameter of superior mesenteric artery (SMA). We assessed whether MDCT was as useful as angiography for the diagnosis of NOMI. Materials and methods: Four patients who were diagnosed with NOMI were retrospectively analyzed. All patients had 8-row MDCT followed by laparotomy. Two of them underwent angiography after MDCT. The morphology and diameter of SMA of these cases was analyzed on multi-planar reconstructed (MPR) images. The mean diameter of SMA of NOMI cases was compared to that of 13 control cases. Results: MPR images of all NOMI cases showed irregular narrowing of the SMA, spasm of the arcades of SMA, and poor demonstration of intramural vessels. MPR images of two patients who had angiography were concordant with their angiograms. The mean diameter of SMA of NOMI patients was 3.4 ± 1.1 mm, which was statistically smaller than that of 13 control patients, 6.0 ± 1.5 mm (P < 0.05, Wilcoxon rank sum tests). Conclusion: Angiography has been recognized essential for the diagnosis of NOMI. This study shows the possibility of MDCT to be an equivalently useful modality compared to angiography for the diagnosis of NOMI by interpreting morphologic appearance and diameter of SMA. Introduction of MDCT in the decision tree of NOMI treatment may bring the benefit of prompt diagnosis and subsequent early and efficient initiation of therapy, which may improve the mortality.

  9. Dependence of reconstructed image characteristics on the observation condition in light-in-flight recording by holography.

    Science.gov (United States)

    Komatsu, Aya; Awatsuji, Yasuhiro; Kubota, Toshihiro

    2005-08-01

    We analyze the dependence of the reconstructed image characteristic on the observation condition in the light-in-flight recording by holography both theoretically and experimentally. This holography makes it possible to record a propagating light pulse. We have found that the shape of the reconstructed image is changed when the observation position is vertically moved along the hologram plane. The reconstructed image is numerically simulated on the basis of the theory and is experimentally obtained by using a 373 fs pulsed laser. The numerical results agree with the experimental result, and the validity of the theory is verified. Also, experimental results are analyzed and the restoration of the reconstructed image is discussed.

  10. Characteristics of Cranial Aneurysmal Bone Cyst on Computed Tomography and Magnetic Resonance Imaging

    Directory of Open Access Journals (Sweden)

    Sen-Ping Lin

    2007-01-01

    Full Text Available Aneurysmal bone cysts are benign bone tumors that most commonly occur in people younger than 30 years. The cysts are most often found in the metaphyses of long bones and rarely affect the skull. We present a 54-year-old woman with a rapidly enlarging mass in the left occipital region that caused tenderness for 2 weeks. Computed tomography (CT revealed an expansile, osteolytic lesion with characteristic soap-bubble appearance and fluid-fluid levels. Magnetic resonance images showed a dark rim surrounding the lesion, as well as multilocular spaces with fluid-fluid levels. The tumor was soft, fragile, and pulsatile during surgery. The patient was treated with en bloc resection of the tumor with cranioplasty. Follow-up CT 5 months later showed no evidence of recurrence. [J Formos Med Assoc 2007;106(3:255-259

  11. Colonic angiodysplasia on CT colonography: case report and characteristic imaging findings

    Directory of Open Access Journals (Sweden)

    Laura Filograna, MD

    2017-12-01

    Full Text Available Gastrointestinal angiodysplasia represents the cause of 6% of lower gastrointestinal tract bleeding, particularly in the elderly. Because of the common presentation and age range of affected patients, often patients with occult or massive gastrointestinal bleedings are investigated with colonoscopy, in the suspect of colonic cancer. Other methods are capsule enteroscopy, angiography, double-contrast barium enema, computed tomography angiography, and radionuclide scanning. In this contribution, we describe a case of colonic angiodysplasia first suspected during computed tomography colonography performed after an incomplete colonoscopy in a patient with recent anemization. The purpose is to highlight the computed tomography colonography imaging characteristics of this rare finding during such examination performed due to suspected colon carcinoma as a complementary or substitutive method of colonoscopy.

  12. Red lesion detection using background estimation and lesions characteristics in diabetic retinal image

    Science.gov (United States)

    Zhang, Dongbo; Peng, Yinghui; Yi, Yao; Shang, Xingyu

    2013-10-01

    Detection of red lesions [hemorrhages (HRs) and microaneurysms (MAs)] is crucial for the diagnosis of early diabetic retinopathy. A method based on background estimation and adapted to specific characteristics of HRs and MAs is proposed. Candidate red lesions are located by background estimation and Mahalanobis distance measure and then some adaptive postprocessing techniques, which include vessel detection, nonvessel exclusion based on shape analysis, and noise points exclusion by double-ring filter (only used for MAs detection), are conducted to remove nonlesion pixels. The method is evaluated on our collected image dataset, and experimental results show that it is better than or approximate to other previous approaches. It is effective to reduce the false-positive and false-negative results that arise from incomplete and inaccurate vessel structure.

  13. Acceleration Characteristics of a Rock Slide Using the Particle Image Velocimetry Technique

    Directory of Open Access Journals (Sweden)

    Guoqing Chen

    2016-01-01

    Full Text Available The Particle Image Velocimetry (PIV technique with high precision and spatial resolution is a suitable sensor for flow field experiments. In this paper, the PIV technology was used to monitor the development of a displacement field, velocity field and acceleration field of a rock slide. It was found that the peak acceleration of the sliding surface appeared earlier than the peak acceleration of the sliding body. The characteristics of the rock slide including the short failure time, high velocities, and large accelerations indicate that the sliding forces and energy release rate of the slope are high. The deformation field showed that the sliding body was sliding outwards along the sliding surface while the sliding bed moved in an opposite direction. Moving upwards at the top of the sliding bed can be one of the warning signs for rock slide failure.

  14. Anterior mediastinal masses in the Framingham Heart Study: Prevalence and CT image characteristics

    International Nuclear Information System (INIS)

    Araki, Tetsuro; Nishino, Mizuki; Gao, Wei; Dupuis, Josée; Washko, George R.; Hunninghake, Gary M.; Murakami, Takamichi; O’Connor, George T.; Hatabu, Hiroto

    2015-01-01

    To investigate the prevalence and CT image characteristics of anterior mediastinal masses in a population-based cohort and their association with the demographics of the participants. Chest CT scans of 2571 Framingham Heart Study participants (mean age 58.9 years, 51% female) were evaluated by two board-certified radiologists with expertise in thoracic imaging for the presence of anterior mediastinal masses, their shape, contour, location, invasion of adjacent structures, fat content, and calcification. For participants with anterior mediastinal masses, a previous cardiac CT scan was reviewed for interval size change of the masses, when available. The demographics of the participants were studied for any association with the presence of anterior mediastinal masses. Of 2571, 23 participants (0.9%, 95% CI: 0.6–1.3) had anterior mediastinal masses on CT. The most common CT characteristics were oval shape, lobular contour, and midline location, showing soft tissue density (median 32.1 HU). Fat content was detected in a few cases (9%, 2/23). Six out of eight masses with available prior cardiac CT scans demonstrated an interval growth over a median period of 6.5 years. No risk factors for anterior mediastinal masses were detected among participants’ demographics, including age, sex, BMI, and cigarette smoking. The prevalence of anterior mediastinal masses is 0.9% in the Framingham Heart Study. Those masses may increase in size when observed over 5–7 years. Investigation of clinical significance in incidentally found anterior mediastinal masses with a longer period of follow-up would be necessary

  15. Image Features Based on Characteristic Curves and Local Binary Patterns for Automated HER2 Scoring

    Directory of Open Access Journals (Sweden)

    Ramakrishnan Mukundan

    2018-02-01

    Full Text Available This paper presents novel feature descriptors and classification algorithms for the automated scoring of HER2 in Whole Slide Images (WSI of breast cancer histology slides. Since a large amount of processing is involved in analyzing WSI images, the primary design goal has been to keep the computational complexity to the minimum possible level and to use simple, yet robust feature descriptors that can provide accurate classification of the slides. We propose two types of feature descriptors that encode important information about staining patterns and the percentage of staining present in ImmunoHistoChemistry (IHC-stained slides. The first descriptor is called a characteristic curve, which is a smooth non-increasing curve that represents the variation of percentage of staining with saturation levels. The second new descriptor introduced in this paper is a local binary pattern (LBP feature curve, which is also a non-increasing smooth curve that represents the local texture of the staining patterns. Both descriptors show excellent interclass variance and intraclass correlation and are suitable for the design of automatic HER2 classification algorithms. This paper gives the detailed theoretical aspects of the feature descriptors and also provides experimental results and a comparative analysis.

  16. Renal water molecular diffusion characteristics in healthy native kidneys: assessment with diffusion tensor MR imaging.

    Directory of Open Access Journals (Sweden)

    Zhenfeng Zheng

    Full Text Available BACKGROUND: To explore the characteristics of diffusion tensor imaging (DTI and magnetic resonance (MR imaging in healthy native kidneys. METHODS: Seventy-three patients without chronic kidney disease underwent DTI-MRI with spin echo-echo planar (SE-EPI sequences accompanied by an array spatial sensitivity encoding technique (ASSET. Cortical and medullary mean, axial and radial diffusivity (MD, AD and RD, fractional anisotropy (FA and primary, secondary and tertiary eigenvalues (λ1, λ2, λ3 were analysed in both kidneys and in different genders. RESULTS: Cortical MD, λ2, λ3, and RD values were higher than corresponding medullary values. The cortical FA value was lower than the medullary FA value. Medullary λ1 and RD values in the left kidney were lower than in the right kidney. Medullary λ2, and λ3 values in women were higher than those in men. Medullary FA values in women were lower than those in men. Medullary FA (r = 0.351, P = 0.002 and λ1 (r = 0.277, P = 0.018 positively correlated with eGFR. Medullary FA (r = -0.25, P = 0.033 negatively correlated with age. CONCLUSIONS: Renal water molecular diffusion differences exist in human kidneys and genders. Age and eGFR correlate with medullary FA and primary eigenvalue.

  17. CSF Venous Fistulas in Spontaneous Intracranial Hypotension: Imaging Characteristics on Dynamic and CT Myelography.

    Science.gov (United States)

    Kranz, Peter G; Amrhein, Timothy J; Gray, Linda

    2017-12-01

    The objective of this study is to describe the anatomic and imaging features of CSF venous fistulas, which are a recently reported cause of spontaneous intracranial hypotension (SIH). We retrospectively reviewed the records of patients with SIH caused by CSF venous fistulas who received treatment at our institution. The anatomic details of each fistula were recorded. Attenuation of the veins involved by the fistula was compared with that of adjacent control veins on CT myelography (CTM). Visibility of the CSF venous fistula on CTM and a modified conventional myelography technique we refer to as dynamic myelography was also compared. Twenty-two cases of CSF venous fistula were identified. The fistulas were located between T4 and L1. Ninety percent occurred without a concurrent epidural CSF leak. In most cases (82%), the CSF venous fistula originated from a nerve root sleeve diverticulum. On CTM, the abnormal veins associated with the CSF venous fistula were seen in a paravertebral location in 45% of cases, centrally within the epidural venous plexus in 32%, and lateral to the spine in 23%. Differences in attenuation between the fistula veins and the control veins was highly statistically significant (p CSF venous fistulas are an important cause of SIH that can be detected on both CTM and dynamic myelograph y and may occur without an epidural CSF leak. Familiarity with the imaging characteristics of these lesions is critical to providing appropriate treatment to patients with SIH.

  18. Accurate Analysis of Target Characteristic in Bistatic SAR Images: A Dihedral Corner Reflectors Case

    Directory of Open Access Journals (Sweden)

    Dongyang Ao

    2017-12-01

    Full Text Available The dihedral corner reflectors are the basic geometric structure of many targets and are the main contributions of radar cross section (RCS in the synthetic aperture radar (SAR images. In stealth technologies, the elaborate design of the dihedral corners with different opening angles is a useful approach to reduce the high RCS generated by multiple reflections. As bistatic synthetic aperture sensors have flexible geometric configurations and are sensitive to the dihedral corners with different opening angles, they specially fit for the stealth target detections. In this paper, the scattering characteristic of dihedral corner reflectors is accurately analyzed in bistatic synthetic aperture images. The variation of RCS with the changing opening angle is formulated and the method to design a proper bistatic radar for maximizing the detection capability is provided. Both the results of the theoretical analysis and the experiments show the bistatic SAR could detect the dihedral corners, under a certain bistatic angle which is related to the geometry of target structures.

  19. Accurate Analysis of Target Characteristic in Bistatic SAR Images: A Dihedral Corner Reflectors Case

    Science.gov (United States)

    Ao, Dongyang; Hu, Cheng; Tian, Weiming

    2017-01-01

    The dihedral corner reflectors are the basic geometric structure of many targets and are the main contributions of radar cross section (RCS) in the synthetic aperture radar (SAR) images. In stealth technologies, the elaborate design of the dihedral corners with different opening angles is a useful approach to reduce the high RCS generated by multiple reflections. As bistatic synthetic aperture sensors have flexible geometric configurations and are sensitive to the dihedral corners with different opening angles, they specially fit for the stealth target detections. In this paper, the scattering characteristic of dihedral corner reflectors is accurately analyzed in bistatic synthetic aperture images. The variation of RCS with the changing opening angle is formulated and the method to design a proper bistatic radar for maximizing the detection capability is provided. Both the results of the theoretical analysis and the experiments show the bistatic SAR could detect the dihedral corners, under a certain bistatic angle which is related to the geometry of target structures. PMID:29271917

  20. Characteristics of myocardial perfusion imaging and coronary artery angiography in patients of NIDDM complicated with AMI

    International Nuclear Information System (INIS)

    Zhao Peiqin; Zhao Jinhua; Qin Mingzhao; Dai HaoJie; Zhang Runwu; Xiao Fen

    2001-01-01

    Objective: To investigate the characteristic changes of myocardial perfusion imaging and coronary artery angiography in patients of acute myocardial infarction (AMI) with underlined type 2 diabetes mellitus. Methods: 25 type 2 diabetes mellitus patients were enrolled for having clinical manifestation of AMI. Ten inpatients with AMI of simple coronary heart disease origin were served as controls. All subjects underwent both myocardial perfusion imagings (resting and nitroglycerine invention) and coronary artery angiography. Results: Compared to controls (40%), type 2 diabetes mellitus + AMI group had higher rate of multivessel disease (60%). For type 2 diabetes mellitus + AMI patients, 129/400 segments (32.25%) showed fixed defect, 25/160 segments (15.62%) in controls. Conclusions: For type 2 diabetes mellitus + AMI group, myocardial perfusion defects are widely distributed and multivessel or severe stenosis is more often presented. Good correlation exists between abnormal segments and angiographic lesions in both the number of segments involved and the severity of the lesions. Radionuclide myocardial perfusion is therefore considered a useful screening test not inferior to angiography, especially for those who are not tolerant enough to undergoing angiography

  1. The clinical and imaging characteristics of delayed encephalopathy after acute carbon monoxide poisoning

    International Nuclear Information System (INIS)

    Huang Chuming; Yin Zhao; Fang Yannan; Hong Weimin; Zeng Xianjie; Wang Tianwen

    2008-01-01

    Objective: To discuss the clinical and imaging characteristics of delayed encephalopathy after acute carbon monoxide poisoning (DEACMP). Methods: The clinical data of 14 patients with DEACMP were respectively analyzed. Results: Initial symptom included mentally falling (MMSE rate < 20 points) in 14 patients (100%), incontinence of urine in 11 patients (78%). Relatively significant increase of hematoma (HCT) (average level 0.503±0.027) was found in 6 patients. Three kinds of brain magnetic resonance imaging (MRI) appearance including diffuse white matter lesion, cortical lesion and basal nuclei lesion often existed in association. Therapy for improving circulation was given in 14 patients, and therapy with hormone was given in 9 patients; with 85% improvement rate. 5 patients without hormone therapy but with improving circulation therapy also received improvement. Conclusion: High level of HCT might be one of the causes of DECACMP due to acute disturbance of brain micro-circulation.. Close monitoring the change of HCT levels should be adopted for at least 3-6 months during therapy. Therapy for improving circulation and for anti-agglutination of platelets should be performed besides the routine high-tension oxygen therapy. Low FA value on DTI indicates the occurrence of a demyelization change in the brain long tract fibers, which indicated therapeutic effect of hormone treatment. And, therefore it would be better to perform DTI scan before therapy for individualized therapy. (authors)

  2. Automated Method for the Rapid and Precise Estimation of Adherent Cell Culture Characteristics from Phase Contrast Microscopy Images

    Science.gov (United States)

    Jaccard, Nicolas; Griffin, Lewis D; Keser, Ana; Macown, Rhys J; Super, Alexandre; Veraitch, Farlan S; Szita, Nicolas

    2014-01-01

    The quantitative determination of key adherent cell culture characteristics such as confluency, morphology, and cell density is necessary for the evaluation of experimental outcomes and to provide a suitable basis for the establishment of robust cell culture protocols. Automated processing of images acquired using phase contrast microscopy (PCM), an imaging modality widely used for the visual inspection of adherent cell cultures, could enable the non-invasive determination of these characteristics. We present an image-processing approach that accurately detects cellular objects in PCM images through a combination of local contrast thresholding and post hoc correction of halo artifacts. The method was thoroughly validated using a variety of cell lines, microscope models and imaging conditions, demonstrating consistently high segmentation performance in all cases and very short processing times (image). Based on the high segmentation performance, it was possible to precisely determine culture confluency, cell density, and the morphology of cellular objects, demonstrating the wide applicability of our algorithm for typical microscopy image processing pipelines. Furthermore, PCM image segmentation was used to facilitate the interpretation and analysis of fluorescence microscopy data, enabling the determination of temporal and spatial expression patterns of a fluorescent reporter. We created a software toolbox (PHANTAST) that bundles all the algorithms and provides an easy to use graphical user interface. Source-code for MATLAB and ImageJ is freely available under a permissive open-source license. Biotechnol. Bioeng. 2014;111: 504–517. © 2013 Wiley Periodicals, Inc. PMID:24037521

  3. MR imaging characteristics and clinical symptoms related to displaced meniscal flap tears

    Energy Technology Data Exchange (ETDEWEB)

    Lance, Valentin; Heilmeier, Ursula R.; Joseph, Gabby B.; Steinbach, Lynne; Link, Thomas M. [University of California, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States); Ma, Benjamin [University of California, Department of Orthopedic Surgery and Sports Medicine, San Francisco (United States)

    2014-11-16

    The purpose of our study was (1) to analyze the flap tear location, direction of displacement and size on magnetic resonance (MR) imaging, (2) to describe associated knee abnormalities including presence of effusion, synovitis, bone marrow edema pattern or ligamentous tear, and (3) to assess clinical findings found with flap tears, including the pain score, and determine differences between operative and nonoperative groups. A retrospective radiology database search over the last 3 years identified 238 patients with flap tears, of which ultimately 58 with isolated flap tears were included after exclusion of patients with other significant knee internal derangement, severe degenerative change or prior surgery. MR studies of the knee were analyzed by two radiologists. Imaging characteristics were correlated with associated knee abnormalities and clinical findings. Statistical analysis employed linear and logistic regression models. Inter- and intrareader reliability was calculated. The medial meniscus was the most common site of flap tears (52/60, 87 %), with inferior displacement (47/60, 78 %). The degree of tibial cartilage loss had a positive correlation with the visual analog pain scale (p = 0.03). Patients who underwent arthroscopy were younger than those who did not (p = 0.01) and more likely to have a positive clinical McMurray test (p = 0.01). Medially and inferiorly displaced flap tears are the most common tear pattern. Those undergoing arthroscopy are more likely to have positive meniscal signs on clinical examination. A greater degree of cartilage loss involving the tibia on MR imaging was associated with increasing visual analog pain scores. (orig.)

  4. MR imaging characteristics and clinical symptoms related to displaced meniscal flap tears

    International Nuclear Information System (INIS)

    Lance, Valentin; Heilmeier, Ursula R.; Joseph, Gabby B.; Steinbach, Lynne; Link, Thomas M.; Ma, Benjamin

    2015-01-01

    The purpose of our study was (1) to analyze the flap tear location, direction of displacement and size on magnetic resonance (MR) imaging, (2) to describe associated knee abnormalities including presence of effusion, synovitis, bone marrow edema pattern or ligamentous tear, and (3) to assess clinical findings found with flap tears, including the pain score, and determine differences between operative and nonoperative groups. A retrospective radiology database search over the last 3 years identified 238 patients with flap tears, of which ultimately 58 with isolated flap tears were included after exclusion of patients with other significant knee internal derangement, severe degenerative change or prior surgery. MR studies of the knee were analyzed by two radiologists. Imaging characteristics were correlated with associated knee abnormalities and clinical findings. Statistical analysis employed linear and logistic regression models. Inter- and intrareader reliability was calculated. The medial meniscus was the most common site of flap tears (52/60, 87 %), with inferior displacement (47/60, 78 %). The degree of tibial cartilage loss had a positive correlation with the visual analog pain scale (p = 0.03). Patients who underwent arthroscopy were younger than those who did not (p = 0.01) and more likely to have a positive clinical McMurray test (p = 0.01). Medially and inferiorly displaced flap tears are the most common tear pattern. Those undergoing arthroscopy are more likely to have positive meniscal signs on clinical examination. A greater degree of cartilage loss involving the tibia on MR imaging was associated with increasing visual analog pain scores. (orig.)

  5. In situ KPFM imaging of local photovoltaic characteristics of structured organic photovoltaic devices.

    Science.gov (United States)

    Watanabe, Satoshi; Fukuchi, Yasumasa; Fukasawa, Masako; Sassa, Takafumi; Kimoto, Atsushi; Tajima, Yusuke; Uchiyama, Masanobu; Yamashita, Takashi; Matsumoto, Mutsuyoshi; Aoyama, Tetsuya

    2014-02-12

    Here, we discuss the local photovoltaic characteristics of a structured bulk heterojunction, organic photovoltaic devices fabricated with a liquid carbazole, and a fullerene derivative based on analysis by scanning kelvin probe force microscopy (KPFM). Periodic photopolymerization induced by an interference pattern from two laser beams formed surface relief gratings (SRG) in the structured films. The surface potential distribution in the SRGs indicates the formation of donor and acceptor spatial distribution. Under illumination, the surface potential reversibly changed because of the generation of fullerene anions and hole transport from the films to substrates, which indicates that we successfully imaged the local photovoltaic characteristics of the structured photovoltaic devices. Using atomic force microscopy, we confirmed the formation of the SRG because of the material migration to the photopolymerized region of the films, which was induced by light exposure through photomasks. The structuring technique allows for the direct fabrication and the control of donor and acceptor spatial distribution in organic photonic and electronic devices with minimized material consumption. This in situ KPFM technique is indispensable to the fabrication of nanoscale electron donor and electron acceptor spatial distribution in the devices.

  6. A Detailed Look at the Performance Characteristics of the Lightning Imaging Sensor

    Science.gov (United States)

    Zhang, Daile; Cummins, Kenneth L.; Bitzer, Phillip; Koshak, William J.

    2018-01-01

    The Lightning Imaging Sensor (LIS) on board the Tropical Rainfall Measuring Mission (TRMM) effectively reached its end of life on April 15, 2015 after 17+ years of observation. Given the wealth of information in the archived LIS lightning data, and growing use of optical observations of lightning from space throughout the world, it is still of importance to better understand LIS calibration and performance characteristics. In this work, we continue our efforts to quantify the optical characteristics of the LIS pixel array, and to further characterize the detection efficiency and location accuracy of LIS. The LIS pixel array was partitioned into four quadrants, each having its own signal amplifier and digital conversion hardware. In addition, the sensor optics resulted in a decreasing sensitivity with increasing displacement from the center of the array. These engineering limitations resulted in differences in the optical emissions detected across the pixel array. Our work to date has shown a 20% increase in the count of the lightning events detected in one of the LIS quadrants, because of a lower detection threshold. In this study, we will discuss our work in progress on these limitations, and their potential impact on the group- and flash-level parameters.

  7. Magnetic resonance imaging characteristics in four dogs with central nervous system neosporosis.

    Science.gov (United States)

    Parzefall, Birgit; Driver, Colin J; Benigni, Livia; Davies, Emma

    2014-01-01

    Neosporosis is a polysystemic disease that can affect dogs of any age and can cause inflammation of the central nervous system. Antemortem diagnosis can be challenging, as clinical and conventional laboratory test findings are often nonspecific. A previous report described cerebellar lesions in brain MRI studies of seven dogs and proposed that these may be characteristic for central nervous system Neosporosis. The purpose of this retrospective study was to describe MRI characteristics in another group of dogs with confirmed central nervous system neosporosis and compare them with the previous report. The hospital's database was searched for dogs with confirmed central nervous system neosporosis and four observers recorded findings from each dog's MRI studies. A total of four dogs met inclusion criteria. Neurologic examination was indicative of a forebrain and cerebellar lesion in dog 2 and multifocal central nervous system disease in dogs 1, 3, and 4. Magnetic resonance imaging showed mild bilateral and symmetrical cerebellar atrophy in three of four dogs (dogs 2, 3, 4), intramedullary spinal cord changes in two dogs (dogs 3, 4) and a mesencephalic and metencephalic lesion in one dog (dog 2). Multifocal brain lesions were recognized in two dogs (dogs 1, 4) and were present in the thalamus, lentiform nucleus, centrum semiovale, internal capsule, brainstem and cortical gray matter of the frontal, parietal or temporal lobe. Findings indicated that central nervous system neosporosis may be characterized by multifocal MRI lesions as well as cerebellar involvement in dogs. © 2014 American College of Veterinary Radiology.

  8. Do Magnetic Resonance Imaging Characteristics of Full-Thickness Rotator Cuff Tears Correlate With Sleep Disturbance?

    Science.gov (United States)

    Reyes, Bryan A; Hull, Brandon R; Kurth, Alexander B; Kukowski, Nathan R; Mulligan, Edward P; Khazzam, Michael S

    2017-11-01

    Many patients with rotator cuff tears suffer from nocturnal shoulder pain, resulting in sleep disturbance. To determine whether rotator cuff tear size correlated with sleep disturbance in patients with full-thickness rotator cuff tears. Cross-sectional study; Level of evidence, 3. Patients with a diagnosis of unilateral full-thickness rotator cuff tears (diagnosed via magnetic resonance imaging [MRI]) completed the Pittsburgh Sleep Quality Index (PSQI), a visual analog scale (VAS) quantifying their shoulder pain, and the American Shoulder and Elbow Surgeons (ASES) questionnaire. Shoulder MRI scans were analyzed for anterior-posterior tear size (mm), tendon retraction (mm), Goutallier grade (0-4), number of tendons involved (1-4), muscle atrophy (none, mild, moderate, or severe), and humeral head rise (present or absent). Bivariate correlations were calculated between the MRI characteristics and baseline survey results. A total of 209 patients with unilateral full-thickness rotator cuff tears were included in this study: 112 (54%) female and 97 (46%) male (mean age, 64.1 years). On average, shoulder pain had been present for 24 months. The mean PSQI score was 9.8, and the mean VAS score was 5.0. No significant correlations were found between any of the rotator cuff tear characteristics and sleep quality. Only tendon retraction had a significant correlation with pain. Although rotator cuff tears are frequently associated with nocturnal pain and sleep disruption, this study demonstrated that morphological characteristics of full-thickness rotator cuff tears, such as size and tendon retraction, do not correlate with sleep disturbance and have little to no correlation with pain levels.

  9. Performance characteristics of dedicated molecular breast imaging systems at low doses

    Energy Technology Data Exchange (ETDEWEB)

    Long, Zaiyang; Conners, Amy L.; Hunt, Katie N.; Hruska, Carrie B.; O’Connor, Michael K., E-mail: mkoconnor@mayo.edu [Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States)

    2016-06-15

    Purpose: The purpose of this study was to compare the system performance characteristics and lesion detection capability of two molecular breast imaging (MBI) systems: a multicrystal sodium iodide (NaI)-based single-head system and a cadmium zinc telluride (CZT)-based dual-head system at low administered doses (150–300 MBq) of Tc-99m sestamibi. Methods: System performance characteristics including count sensitivity, uniformity, energy resolution, and spatial resolution were measured using standard NEMA methods, or a modified version thereof in cases where the standard NEMA protocol could not be applied. A contrast-detail phantom with 48 lesions at varying depths from the collimator surface was used to assess lesion contrast-to-noise-ratio (CNR) using background count densities comparable to those observed in patient studies performed with administered doses of 150 MBq Tc-99m sestamibi. Lesions with CNR >3 were deemed to be detectable. Thirty patients undergoing MBI examinations with administered doses of 150–300 MBq were scanned for an additional view on the pixelated NaI system. CNR was calculated for lesions observed on patient images. Background count densities of patient images were measured and compared between the two systems. Results: Over the central field of view, integral and differential uniformity were 6.1% and 4.2%, respectively, for the pixelated NaI system, and 3.8% and 2.7%, respectively, for the CZT system. Count sensitivity was 10.8 kcts/min/MBq for the NaI system and 32.9 kcts/min/MBq for the CZT system. Energy resolution was 13.5% on the pixelated NaI system and 4.5% on the CZT system. Spatial resolution (full-width at half-maximum) for the pixelated NaI detector was 4.2 mm at a distance of 1.2 cm from the collimator and 5.2 mm at 3.1 cm. Spatial resolution of a single CZT detector was 2.9 mm at a distance of 1.2 cm from the collimator and 4.7 mm at 3.1 cm. Effective spatial resolution obtained with dual-head CZT was below 4.7 mm throughout

  10. Perturbation resilience and superiorization of iterative algorithms

    International Nuclear Information System (INIS)

    Censor, Y; Davidi, R; Herman, G T

    2010-01-01

    Iterative algorithms aimed at solving some problems are discussed. For certain problems, such as finding a common point in the intersection of a finite number of convex sets, there often exist iterative algorithms that impose very little demand on computer resources. For other problems, such as finding that point in the intersection at which the value of a given function is optimal, algorithms tend to need more computer memory and longer execution time. A methodology is presented whose aim is to produce automatically for an iterative algorithm of the first kind a 'superiorized version' of it that retains its computational efficiency but nevertheless goes a long way toward solving an optimization problem. This is possible to do if the original algorithm is 'perturbation resilient', which is shown to be the case for various projection algorithms for solving the consistent convex feasibility problem. The superiorized versions of such algorithms use perturbations that steer the process in the direction of a superior feasible point, which is not necessarily optimal, with respect to the given function. After presenting these intuitive ideas in a precise mathematical form, they are illustrated in image reconstruction from projections for two different projection algorithms superiorized for the function whose value is the total variation of the image

  11. Superior versus inferior Ahmed glaucoma valve implantation.

    Science.gov (United States)

    Pakravan, Mohammad; Yazdani, Shahin; Shahabi, Camelia; Yaseri, Mehdi

    2009-02-01

    To compare the efficacy and safety of Ahmed glaucoma valve (AGV) (New World Medical Inc., Rancho Cucamonga, CA) implantation in the superior versus inferior quadrants. Prospective parallel cohort study. A total of 106 eyes of 106 patients with refractory glaucoma. Consecutive patients with refractory glaucoma underwent AGV implantation in the superior or inferior quadrants. Main outcome measures included intraocular pressure (IOP) and rate of complications. Other outcome measures included best corrected visual acuity (BCVA), number of glaucoma medications, and success rate (defined as at least 30% IOP reduction and 5glaucoma surgery, phthisis bulbi, or loss of light perception. Of a total of 106 eyes, 58 and 48 eyes underwent AGV implantation in the superior and inferior quadrants, respectively. Baseline characteristics were comparable in the study groups, except for preoperative IOP, which was higher in the superior group (P = 0.01). Patients were followed for a mean period of 10.6+/-8.49 months and 10.58+/-6.75 months in the superior and inferior groups, respectively (P = 0.477). BCVA was comparable between the groups at all postoperative visits (P>0.122). After 1 year, statistically significant but comparable IOP reduction from baseline (Pglaucoma medications was comparable after 1 year (1.3+/-1.2 vs. 1.9+/-0.8 for superior and inferior implants, respectively, P = 0.256). Success rates were also similar at 1 year: 27 eyes (81.8%) versus 20 eyes (95.2%) for superior and inferior implants, respectively (P = 0.227). However, the overall rate of complications, such as implant exposure necessitating removal, cosmetically unappealing appearance, and endophthalmitis, was higher in the inferior group: 12 eyes (25%) versus 3 eyes (5.2%) for superior and inferior groups, respectively, (P = 0.004). Superior and inferior AGV implants have similar intermediate efficacy in terms of IOP reduction, decrease in number of glaucoma medications, and preservation of vision. However

  12. Sobredentadura total superior implantosoportada

    Directory of Open Access Journals (Sweden)

    Luis Orlando Rodríguez García

    2010-06-01

    Full Text Available Se presenta un caso de un paciente desdentado total superior, rehabilitado en la consulta de implantología de la Clínica "Pedro Ortiz" del municipio Habana del Este en Ciudad de La Habana, Cuba, en el año 2009, mediante prótesis sobre implantes osteointegrados, técnica que se ha incorporado a la práctica estomatológica en Cuba como alternativa al tratamiento convencional en los pacientes desdentados totales. Se siguió un protocolo que comprendió una fase quirúrgica, procedimiento con o sin realización de colgajo y carga precoz o inmediata. Se presenta un paciente masculino de 56 años de edad, que acudió a la consulta multidisciplinaria, preocupado, porque se le habían elaborado tres prótesis en los últimos dos años y ninguna reunía los requisitos de retención que él necesitaba para sentirse seguro y cómodo con las mismas. El resultado final fue la satisfacción total del paciente, con el mejoramiento de la calidad estética y funcional.

  13. Intracranial metastatic mucinous adrenocarcinoma with characteristic features on diffusion-weighted imaging and in vivo magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Guruprasad, Ashwathnarayan S.; Chandrashekar, Hoskote S.; Jayakumar, Peruvumba N.; Srikanth, Subbamma G.; Shankar, Susarla K.

    2004-01-01

    Intracranial abscesses and metastases are common lesions that might not be differentiated on routine MR I alone. In vivo proton spectroscopy and diffusion-weighted imaging have been used as complementary investigations for improved tissue characterization. In the present report we illustrate the role of mucin and its contribution to signal characteristics on diffusion-weighted imaging in a metastatic mucinous adenocarcinoma Copyright (2004) Blackwell Publishing Asia Pty Ltd

  14. Sacroiliac joint injection using the posterior superior iliac spines as ...

    African Journals Online (AJOL)

    Limitations in the availability of such image guided techniques in health ... School of Medical Sciences, University of Science and Technology between 2006 and ... The needle position from the posterior superior iliac spine and its angle of ...

  15. Estimating envelope thermal characteristics from single point in time thermal images

    Science.gov (United States)

    Alshatshati, Salahaldin Faraj

    Energy efficiency programs implemented nationally in the U.S. by utilities have rendered savings which have cost on average 0.03/kWh. This cost is still well below generation costs. However, as the lowest cost energy efficiency measures are adopted, this the cost effectiveness of further investment declines. Thus there is a need to more effectively find the most opportunities for savings regionally and nationally, so that the greatest cost effectiveness in implementing energy efficiency can be achieved. Integral to this process. are at scale energy audits. However, on-site building energy audits process are expensive, in the range of US1.29/m2-$5.37/m2 and there are an insufficient number of professionals to perform the audits. Energy audits that can be conducted at-scale and at low cost are needed. Research is presented that addresses at community-wide scales characterization of building envelope thermal characteristics via drive-by and fly-over GPS linked thermal imaging. A central question drives this research: Can single point-in-time thermal images be used to infer U-values and thermal capacitances of walls and roofs? Previous efforts to use thermal images to estimate U-values have been limited to rare steady exterior weather conditions. The approaches posed here are based upon the development two models first is a dynamic model of a building envelope component with unknown U-value and thermal capacitance. The weather conditions prior to the thermal image are used as inputs to the model. The model is solved to determine the exterior surface temperature, ultimately predicted the temperature at the thermal measurement time. The model U-value and thermal capacitance are tuned in order to force the error between the predicted surface temperature and the measured surface temperature from thermal imaging to be near zero. This model is developed simply to show that such a model cannot be relied upon to accurately estimate the U-value. The second is a data

  16. Temporal and spatial evolution characteristics of gas-liquid two-phase flow pattern based on image texture spectrum descriptor

    Science.gov (United States)

    Zhou, Xi-Guo; Jin, Ning-De; Wang, Zhen-Ya; Zhang, Wen-Yin

    2009-11-01

    The dynamic image information of typical gas-liquid two-phase flow patterns in vertical upward pipe is captured by a highspeed dynamic camera. The texture spectrum descriptor is used to describe the texture characteristics of the processed images whose content is represented in the form of texture spectrum histogram, and four time-varying characteristic parameter indexes which represent image texture structure of different flow patterns are extracted. The study results show that the amplitude fluctuation of texture characteristic parameter indexes of bubble flow is lowest and shows very random complex dynamic behavior; the amplitude fluctuation of slug flow is higher and shows intermittent motion behavior between gas slug and liquid slug, and the amplitude fluctuation of churn flow is the highest and shows better periodicity; the amplitude fluctuation of bubble-slug flow is from low to high and oscillating frequence is higher than that of slug flow, and includes the features of both slug flow and bubble flow; the slug-churn flow loses the periodicity of slug flow and churn flow, and the amplitude fluctuation is high. The results indicate that the image texture characteristic parameter indexes of different flow pattern can reflect the flow characteristics of gas-liquid two-phase flow, which provides a new approach to understand the temporal and spatial evolution of flow pattern dynamics.

  17. STUDY ON REMOTE SENSING IMAGE CHARACTERISTICS OF ECOLOGICAL LAND: CASE STUDY OF ORIGINAL ECOLOGICAL LAND IN THE YELLOW RIVER DELTA

    Directory of Open Access Journals (Sweden)

    G. Q. An

    2018-04-01

    Full Text Available Takes the Yellow River Delta as an example, this paper studies the characteristics of remote sensing imagery with dominant ecological functional land use types, compares the advantages and disadvantages of different image in interpreting ecological land use, and uses research results to analyse the changing trend of ecological land in the study area in the past 30 years. The main methods include multi-period, different sensor images and different seasonal spectral curves, vegetation index, GIS and data analysis methods. The results show that the main ecological land in the Yellow River Delta included coastal beaches, saline-alkaline lands, and water bodies. These lands have relatively distinct spectral and texture features. The spectral features along the beach show characteristics of absorption in the green band and reflection in the red band. This feature is less affected by the acquisition year, season, and sensor type. Saline-alkali land due to the influence of some saline-alkaline-tolerant plants such as alkali tent, Tamarix and other vegetation, the spectral characteristics have a certain seasonal changes, winter and spring NDVI index is less than the summer and autumn vegetation index. The spectral characteristics of a water body generally decrease rapidly with increasing wavelength, and the reflectance in the red band increases with increasing sediment concentration. In conclusion, according to the spectral characteristics and image texture features of the ecological land in the Yellow River Delta, the accuracy of image interpretation of such ecological land can be improved.

  18. Study on Remote Sensing Image Characteristics of Ecological Land: Case Study of Original Ecological Land in the Yellow River Delta

    Science.gov (United States)

    An, G. Q.

    2018-04-01

    Takes the Yellow River Delta as an example, this paper studies the characteristics of remote sensing imagery with dominant ecological functional land use types, compares the advantages and disadvantages of different image in interpreting ecological land use, and uses research results to analyse the changing trend of ecological land in the study area in the past 30 years. The main methods include multi-period, different sensor images and different seasonal spectral curves, vegetation index, GIS and data analysis methods. The results show that the main ecological land in the Yellow River Delta included coastal beaches, saline-alkaline lands, and water bodies. These lands have relatively distinct spectral and texture features. The spectral features along the beach show characteristics of absorption in the green band and reflection in the red band. This feature is less affected by the acquisition year, season, and sensor type. Saline-alkali land due to the influence of some saline-alkaline-tolerant plants such as alkali tent, Tamarix and other vegetation, the spectral characteristics have a certain seasonal changes, winter and spring NDVI index is less than the summer and autumn vegetation index. The spectral characteristics of a water body generally decrease rapidly with increasing wavelength, and the reflectance in the red band increases with increasing sediment concentration. In conclusion, according to the spectral characteristics and image texture features of the ecological land in the Yellow River Delta, the accuracy of image interpretation of such ecological land can be improved.

  19. Use of scanner characteristics in iterative image reconstruction for high-resolution positron emission tomography studies of small animals

    Energy Technology Data Exchange (ETDEWEB)

    Brix, G. [Research Program ``Radiological Diagnostics and Therapy``, German Cancer Research Center (DKFZ), Heidelberg (Germany); Doll, J. [Research Program ``Radiological Diagnostics and Therapy``, German Cancer Research Center (DKFZ), Heidelberg (Germany); Bellemann, M.E. [Research Program ``Radiological Diagnostics and Therapy``, German Cancer Research Center (DKFZ), Heidelberg (Germany); Trojan, H. [Research Program ``Radiological Diagnostics and Therapy``, German Cancer Research Center (DKFZ), Heidelberg (Germany); Haberkorn, U. [Research Program ``Radiological Diagnostics and Therapy``, German Cancer Research Center (DKFZ), Heidelberg (Germany); Schmidlin, P. [Research Program ``Radiological Diagnostics and Therapy``, German Cancer Research Center (DKFZ), Heidelberg (Germany); Ostertag, H. [Research Program ``Radiological Diagnostics and Therapy``, German Cancer Research Center (DKFZ), Heidelberg (Germany)

    1997-07-01

    The purpose of this work was to improve of the spatial resolution of a whole-body PET system for experimental studies of small animals by incorporation of scanner characteristics into the process of iterative image reconstruction. The image-forming characteristics of the PET camera were characterized by a spatially variant line-spread function (LSF), which was determined from 49 activated copper-64 line sources positioned over a field of view (FOV) of 21.0 cm. During the course of iterative image reconstruction, the forward projection of the estimated image was blurred with the LSF at each iteration step before the estimated projections were compared with the measured projections. Moreover, imaging studies of a rat and two nude mice were performed to evaluate the imaging properties of our approach in vivo. The spatial resolution of the scanner perpendicular to the direction of projection could be approximated by a one-dimensional Gaussian-shaped LSF with a full-width at half-maximum increasing from 6.5 mm at the centre to 6.7 mm at a radial distance of 10.5 cm. The incorporation of this blurring kernel into the iteration formula resulted in a significantly improved spatial resolution of about 3.9 mm over the examined FOV. As demonstrated by the phantom and the animal experiments, the high-resolution algorithm not only led to a better contrast resolution in the reconstructed emission scans but also improved the accuracy for quantitating activity concentrations in small tissue structures without leading to an amplification of image noise or image mottle. The presented data-handling strategy incorporates the image restoration step directly into the process of algebraic image reconstruction and obviates the need for ill-conditioned ``deconvolution`` procedures to be performed on the projections or on the reconstructed image. In our experience, the proposed algorithm is of special interest in experimental studies of small animals. (orig./AJ). With 9 figs.

  20. Use of scanner characteristics in iterative image reconstruction for high-resolution positron emission tomography studies of small animals

    International Nuclear Information System (INIS)

    Brix, G.; Doll, J.; Bellemann, M.E.; Trojan, H.; Haberkorn, U.; Schmidlin, P.; Ostertag, H.

    1997-01-01

    The purpose of this work was to improve of the spatial resolution of a whole-body PET system for experimental studies of small animals by incorporation of scanner characteristics into the process of iterative image reconstruction. The image-forming characteristics of the PET camera were characterized by a spatially variant line-spread function (LSF), which was determined from 49 activated copper-64 line sources positioned over a field of view (FOV) of 21.0 cm. During the course of iterative image reconstruction, the forward projection of the estimated image was blurred with the LSF at each iteration step before the estimated projections were compared with the measured projections. Moreover, imaging studies of a rat and two nude mice were performed to evaluate the imaging properties of our approach in vivo. The spatial resolution of the scanner perpendicular to the direction of projection could be approximated by a one-dimensional Gaussian-shaped LSF with a full-width at half-maximum increasing from 6.5 mm at the centre to 6.7 mm at a radial distance of 10.5 cm. The incorporation of this blurring kernel into the iteration formula resulted in a significantly improved spatial resolution of about 3.9 mm over the examined FOV. As demonstrated by the phantom and the animal experiments, the high-resolution algorithm not only led to a better contrast resolution in the reconstructed emission scans but also improved the accuracy for quantitating activity concentrations in small tissue structures without leading to an amplification of image noise or image mottle. The presented data-handling strategy incorporates the image restoration step directly into the process of algebraic image reconstruction and obviates the need for ill-conditioned ''deconvolution'' procedures to be performed on the projections or on the reconstructed image. In our experience, the proposed algorithm is of special interest in experimental studies of small animals. (orig./AJ). With 9 figs

  1. Clinical and imaging characteristics and autoantibody analysis of neuromyelitis optica spectrum disorders

    Directory of Open Access Journals (Sweden)

    Nan LIU

    2014-09-01

    Full Text Available Objective To observe the clinical and imaging characteristics and the changes of autoimmune antibodies in the serum and cerebrospinal fluid (CSF of patients with neuromyelitis optica spectrum disorders (NMOSDs.  Methods The data of 10 patients with NMOSDs in Aviation General Hospital of China Medical University from January 2011 to June 2014 were collected. The clinical and imaging features were retrospectively reviewed, and NMO-IgG in serum and CSF, anti-nuclear antibody (ANA, homocysteine (Hcy and thyroid function were analyzed.  Results Cranial and spinal MRI of these patients showed that brain stem was involved in 3 cases, cervical cord in 3 cases, thoracic cord in 6 cases, and cervical-thoracic cord in one case. Serum NMO-IgG were tested in 8 cases, among whom 3 patients were positive (3/8 and 5 were negative (5/8. ANA was positive in one case (1/3, and thyroglobulin (TG antibody and thyroid peroxidase (TPO antibody were positive in 2 cases (2/3. Hypothyroidism occured in 2 cases, hyperthyroidism occured in one case, and Hcy rised in 2 cases.  Conclusions NMOSDs frequently occur in young and middle-aged women. Patients who were highly suspected with NMOSDs should receive tests of autoimmune antibodies in the serum and CSF, and cranial and spinal MRI examination, in order to make a definite diagnosis and receive appropriate treatment. Retesting the autoimmune antibodies should be done in catabasis, in order to identify the relationship between autoimmune antibodies and NMOSDs. doi: 10.3969/j.issn.1672-6731.2014.09.010

  2. Perfusion magnetic resonance imaging characteristics of intracerebral tuberculomas and its role in differentiating tuberculomas from metastases

    International Nuclear Information System (INIS)

    Sankhe, Shilpa; Baheti, Akshay; Ihare, Ashish; Mathur, Shobhit; Dabhade, Poonam; Sarode, Ashish

    2013-01-01

    Background: Intracerebral tuberculomas usually manifest as ring-enhancing of nodular lesions on magnetic resonance imaging (MRI). These imaging findings are also observed in other lesions like metastases and toxoplasmosis. Purpose: To study the MRI perfusion characteristics of tuberculomas and its potential role in their definitive diagnosis. Material and Methods: Thirty-four tuberculomas were evaluated by conventional and perfusion MRI. The relative cerebral blood volume (rCBV) values of the center, peripheral wall, and perilesional neuroparenchymal tissue were calculated using rCBV maps. Ten ring-enhancing metastases were similarly evaluated and rCBV values of their peripheral walls were calculated. Results: Thirty-one of the 34 tuberculomas were ring-enhancing or conglomerate lesions and revealed hypoperfused centers with hyperperfused peripheral walls, with the mean rCBV ± SD being 0.42 ± 0.25 and 2.04 ± 0.61, respectively. Three nodular enhancing lesions showed predominantly homogenous hyperperfusion, with the mean rCBV measuring 2.96 ± 0.39 (mean ± SD). The perilesional neuroparenchyma was hypoperfused in both cases. The metastases revealed mean rCBV ratio of the peripheral wall to be 5.43 ± 2.1 (mean ± SD). Analysis of the values by ROC curve method revealed a cut-off value of ≥3.745 for differentiating ring-enhancing metastases from ring-enhancing tuberculomas. Conclusion: Perfusion MR is a useful tool for the assessment of tuberculomas and can help differentiate them from neoplasms like metastases. It also has a potential role in monitoring therapy and for early detection of drug resistance

  3. Perfusion magnetic resonance imaging characteristics of intracerebral tuberculomas and its role in differentiating tuberculomas from metastases

    Energy Technology Data Exchange (ETDEWEB)

    Sankhe, Shilpa; Baheti, Akshay [Dept. of Radiology, Seth GS Medical Coll. and KEM Hospital, Thane (India)], e-mail: akshaybaheti@gmail.com; Ihare, Ashish; Mathur, Shobhit; Dabhade, Poonam; Sarode, Ashish [Dept. of Radiology, Seth GS Medical Coll. and KEM Hospital, Thane (India)

    2013-04-15

    Background: Intracerebral tuberculomas usually manifest as ring-enhancing of nodular lesions on magnetic resonance imaging (MRI). These imaging findings are also observed in other lesions like metastases and toxoplasmosis. Purpose: To study the MRI perfusion characteristics of tuberculomas and its potential role in their definitive diagnosis. Material and Methods: Thirty-four tuberculomas were evaluated by conventional and perfusion MRI. The relative cerebral blood volume (rCBV) values of the center, peripheral wall, and perilesional neuroparenchymal tissue were calculated using rCBV maps. Ten ring-enhancing metastases were similarly evaluated and rCBV values of their peripheral walls were calculated. Results: Thirty-one of the 34 tuberculomas were ring-enhancing or conglomerate lesions and revealed hypoperfused centers with hyperperfused peripheral walls, with the mean rCBV {+-} SD being 0.42 {+-} 0.25 and 2.04 {+-} 0.61, respectively. Three nodular enhancing lesions showed predominantly homogenous hyperperfusion, with the mean rCBV measuring 2.96 {+-} 0.39 (mean {+-} SD). The perilesional neuroparenchyma was hypoperfused in both cases. The metastases revealed mean rCBV ratio of the peripheral wall to be 5.43 {+-} 2.1 (mean {+-} SD). Analysis of the values by ROC curve method revealed a cut-off value of {>=}3.745 for differentiating ring-enhancing metastases from ring-enhancing tuberculomas. Conclusion: Perfusion MR is a useful tool for the assessment of tuberculomas and can help differentiate them from neoplasms like metastases. It also has a potential role in monitoring therapy and for early detection of drug resistance.

  4. Successful treatment of suspected organizing pneumonia in a patient without typical imaging and pathological characteristic: A case report.

    Science.gov (United States)

    Ailing, Liu; Ning, Xu; Tao, Qu; Aijun, Li

    2017-01-01

    Organizing pneumonia (OP) is a clinicopathological entity characterized by granulation tissue plugs in the lumen of small airways, alveolar ducts, and alveoli. Diagnosis of OP needs the combination of clinical features, imaging and pathology. But it occurs often that there are no typical pathological features to support the diagnosis, which poses a challenge for clinicians' diagnosis and treatment. We diagnosed a case of OP without typical imaging and pathological characteristic and treated successfully. Finally we confirmed the pathological diagnosis. Not every OP case is supported by pathological evidence and typical imaging changes. It is important for us to judge and decide the diagnosis according to clinical experience.

  5. The characteristics of Fugi IP Cassette Type PII and application for radiation oncology quality assurance tests and portal imaging

    International Nuclear Information System (INIS)

    Soh, H.S.; Ung, N.M.; Ng, K.H.

    2008-01-01

    Full text: The advancement of digital imaging has prompted more medical institutions to go filmless. The computed radiography (CR) system is becoming an important tool not only in diagnostic imaging, but also in radiation oncology. A new CR system that was specially designed for the use in radiation oncology. Fuji IP cassette type PII has been introduced to the market in the middle of year 2006. This project aimed to study some basic physical characteristics of this new type of cassette and explore its application for performing quality assurance (QA) tests and portal imaging in radiotherapy. All the images were read by FCR 5000 Plus reader. The image was found to reach its saturation value of 1023 (due to the image was stored in 10 bits data) by depending on the sensitivity value being adjusted. The uniformity test gave the result of 0.12%. The cassette was used to perform the QA tests which were previously performed using film. All the results met the specification as stated in AAPM Task Group 40. The comparison for the portal images of Portal Vision contrast-detail phantom showed that the spatial resolution of the images obtained by CR system (Fujifilm Co.. Ltd.. Tokyo. Japan) were better than the EPID (Varian Medical Systems. Inc.. Palo Alto. USA) and film system (Eastman Kodak Co.. New York. USA). The IP cassette type PII was found to be suitable as an alternative QA test tool and portal imaging in radiotherapy.

  6. Characteristics of NaI detector in positron imaging device HEADTOME employing circular ring array

    International Nuclear Information System (INIS)

    Miura, Shuichi; Kanno, Iwao; Aizawa, Yasuo; Murakami, Matsutaro; Uemura, Kazuo

    1984-01-01

    In positron emission computed tomographs employing circular ring arrays of detectors, the performance of the imaging device has been specified ultimately by the characteristics of the detector. The responses of NaI detector were studied when detecting positron annihilation photon (511 keV). The study was mainly by using the NaI detector used in hybrid emission computed tomography (CT) ''HEADTOME'' we had developed. A series of measurements were carried out positioning two detectors with 40 cm distance and scanning 22 Na point source in water. Both detectors was inclined from 0 0 through 30 0 to change incident angle of positron annihilation toward crystal face. Energy window was set from 100 to 700 keV. The results were presented as follows; 1 Shortening the crystal length from 7 to 5 cm made sensitivity decrease about 10% and resolution deteriorate about 1 mm (FWHM). 2 As the results of varying the width of the crystal, 20 mm width was optimal at any incident angle. 3 The lead septum between the detectors was the thickness of 4 mm enough to reject multiple detector interactions (crosstalk). 4 Beam mask which was made of lead in order to improve spatial resolution and placed on crystal face worked effectively for incident angles from 0 0 to 15 0 but degraded uniformity of spatial resolution from 0 0 to through 30 0 . (author)

  7. Benign submucosal lesions of the stomach and duodenum: Imaging characteristics with endoscopic and pathologic correlation

    International Nuclear Information System (INIS)

    Oh, Jong Young; Nam, Kyung Jin; Choi, Jong Cheol; Cho, Jin Han; Yoon, Seong Kuk; Choi, Sun Seob; Kwon, Hee Jin; Yoon, Jung Hee; Kim, Su Jin

    2008-01-01

    Benign submucosal lesions of the stomach and duodenum are occasionally encountered during endoscopy. But endoscopy has its limitations in the diagnosis and differentiation of these lesions, because submucosal lesions are often difficult to visualize at endoscopy due to minimal change of the overlying mucosa. Furthermore, endoscopic biopsy may not always yield adequate tissue for diagnosis due to the submucosal location of the lesions. For this reason, the role of radiologic imaging is important in the diagnosis of submucosal lesions of the stomach and duodenum. Recent advances in computed tomography (CT) and sonographic technology are helpful in narrowing the differential diagnosis of gastroduodenal submucosal lesions. In contrast to endoscopy and barium studies, CT or ultrasonography (US) provides information about both the gastric wall and the extragastric extent of the disease. Arterial phase contrast enhanced CT enables us to discriminate a mass of submucosal from that of a mucosal origin in the differential diagnosis of gastric or duodenal lesions. Although endoscopic sonography has been considered the better modality in the diagnosis of gastroduodenal submucosal lesions, transabdominal sonography can still be an alternative method to endoscopic sonography in assessing of the origin and character of the submucosal lesions. Some gastroduodenal submucosal lesions have similar radiologic findings that make differentiation difficult. But despite overlaps in radiologic findings, some lesions have characteristic radiologic features that may suggest a specific diagnosis. Knowledge of the differential diagnosis of benign submucosal lesions in the stomach and duodenum may promote correct diagnosis and appropriate treatment

  8. Malignant Pleural Mesothelioma: Are There Imaging Characteristics Associated With Different Histologic Subtypes on Computed Tomography?

    Science.gov (United States)

    Escalon, Joanna G; Harrington, Kate A; Plodkowski, Andrew J; Zheng, Junting; Capanu, Marinela; Zauderer, Marjorie G; Rusch, Valerie W; Ginsberg, Michelle S

    2018-04-02

    Determine imaging characteristics specific to epithelioid (eMPM), sarcomatoid (sMPM), and biphasic (bMPM) subtypes of malignant pleural mesothelioma (MPM) on computed tomography. Preoperative computed tomography scans of patients with MPM were retrospectively assessed for numerous features including primary affected side, volume loss, pleural thickness, pleural calcifications, pleural effusion, and lymphadenopathy. One hundred twenty-five patients with MPM were included. Histologic subdivision was 97 eMPM (77%), 17 bMPM (14%), and 11 sMPM (9%). Nonepithelioid MPM (bMPM and sMPM) was more likely than eMPM to have calcified pleural plaques (P = 0.035). Analyzed separately, bMPM and sMPM each demonstrated calcified plaques more frequently than eMPM, and sMPM more often had internal mammary nodes; however, P values did not reach significance (P = 0.075 and 0.071, respectively). Calcified plaques are significantly more common in nonepithelioid subtypes compared with eMPM. Given the different prognoses and management of MPM subtypes, accurate noninvasive subtype classification is clinically vital.

  9. Effects of Injection Timing on Fluid Flow Characteristics of Partially Premixed Combustion Based on High-Speed Particle Image Velocimetry

    KAUST Repository

    Izadi Najafabadi, Mohammad; Tanov, Slavey; Wang, Hua; Somers, Bart; Johansson, Bengt; Dam, Nico

    2017-01-01

    behavior. The scope of the present study is to investigate the fluid flow characteristics of PPC at different injection timings. To this end, high-speed Particle Image Velocimetry (PIV) is implemented in a light-duty optical engine to measure fluid flow

  10. Magnetic resonance imaging and pathological characteristics of pure mucinous carcinoma in the breast according to echogenicity on ultrasonography

    International Nuclear Information System (INIS)

    Shin, Young Gyung; Kim, Eun Kyung; Kim, Min Jung; Yoon, JUng Hyun; Moon, Hee Jung

    2017-01-01

    The aim of this study was to explore the clinical and pathological characteristics of pure mucinous breast carcinoma (PMBC) according to internal echogenicity on ultrasonography (US). Thirty-three patients with PMBC diagnosed at surgery were included in this study. Cases of PMBC were classified according to internal echogenicity on US. The imaging features on magnetic resonance (MR) imaging and clinicohistopathological characteristics were compared between the hypoechogenic and the isoechogenic to hyperechogenic groups. Eleven cases of PMBC (33.3%) exhibited hypoechogenicity on US, while 22 cases (66.7%) exhibited isoechogenicity or hyperechogenicity. Of the isoechogenic to hyperechogenic PMBCs, 95.5% showed a high signal on T2-weighted images, which was a significantly greater percentage than was observed for the hypoechogenic group (54.5%) (P=0.010). Of the hypoechogenic PMBCs, 63.6% showed a washout pattern in the delayed phase, which was substantially more than the result of 23.8% observed for the isoechogenic to hyperechogenic PMBCs (P=0.053). PMBCs with isoechogenicity or hyperechogenicity were more likely to show a high signal intensity on T2-weighted images than hypoechogenic PMBCs. However, other MR imaging and clinicohistopathological characteristics were not significantly different between the two groups

  11. Comparison of Imaging Characteristics of 124I PET for Determination of Optimal Energy Window on the Siemens Inveon PET

    Directory of Open Access Journals (Sweden)

    A Ram Yu

    2016-01-01

    Full Text Available Purpose.124I has a half-life of 4.2 days, which makes it suitable for imaging over several days over its uptake and washout phases. However, it has a low positron branching ratio (23%, because of prompt gamma coincidence due to high-energy γ-photons (602 to 1,691 keV, which are emitted in cascade with positrons. Methods. In this study, we investigated the optimal PET energy window for 124I PET based on image characteristics of reconstructed PET. Image characteristics such as nonuniformities, recovery coefficients (RCs, and the spillover ratios (SORs of 124I were measured as described in NEMA NU 4-2008 standards. Results. The maximum and minimum prompt gamma coincidence fraction (PGF were 33% and 2% in 350~800 and 400~590 keV, respectively. The difference between best and worst uniformity in the various energy windows was less than 1%. The lowest SORs of 124I were obtained at 350~750 keV in nonradioactive water compartment. Conclusion. Optimal energy window should be determined based on image characteristics. Our developed correction method would be useful for the correction of high-energy prompt gamma photon in 124I PET. In terms of the image quality of 124I PET, our findings indicate that an energy window of 350~750 keV would be optimal.

  12. Magnetic resonance imaging and pathological characteristics of pure mucinous carcinoma in the breast according to echogenicity on ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Young Gyung; Kim, Eun Kyung; Kim, Min Jung; Yoon, JUng Hyun; Moon, Hee Jung [Dept. of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2017-04-15

    The aim of this study was to explore the clinical and pathological characteristics of pure mucinous breast carcinoma (PMBC) according to internal echogenicity on ultrasonography (US). Thirty-three patients with PMBC diagnosed at surgery were included in this study. Cases of PMBC were classified according to internal echogenicity on US. The imaging features on magnetic resonance (MR) imaging and clinicohistopathological characteristics were compared between the hypoechogenic and the isoechogenic to hyperechogenic groups. Eleven cases of PMBC (33.3%) exhibited hypoechogenicity on US, while 22 cases (66.7%) exhibited isoechogenicity or hyperechogenicity. Of the isoechogenic to hyperechogenic PMBCs, 95.5% showed a high signal on T2-weighted images, which was a significantly greater percentage than was observed for the hypoechogenic group (54.5%) (P=0.010). Of the hypoechogenic PMBCs, 63.6% showed a washout pattern in the delayed phase, which was substantially more than the result of 23.8% observed for the isoechogenic to hyperechogenic PMBCs (P=0.053). PMBCs with isoechogenicity or hyperechogenicity were more likely to show a high signal intensity on T2-weighted images than hypoechogenic PMBCs. However, other MR imaging and clinicohistopathological characteristics were not significantly different between the two groups.

  13. Characteristics of a New X-Ray Imaging System for Interventional Procedures: Improved Image Quality and Reduced Radiation Dose.

    Science.gov (United States)

    Schernthaner, Ruediger E; Haroun, Reham R; Nguyen, Sonny; Duran, Rafael; Sohn, Jae Ho; Sahu, Sonia; Chapiro, Julius; Zhao, Yan; Radaelli, Alessandro; van der Bom, Imramsjah M; Mauti, Maria; Hong, Kelvin; Geschwind, Jean-François H; Lin, MingDe

    2018-03-01

    To compare image quality and radiation exposure between a new angiographic imaging system and the preceding generation system during uterine artery embolization (UAE). In this retrospective, IRB-approved two-arm study, 54 patients with symptomatic uterine fibroids were treated with UAE on two different angiographic imaging systems. The new system includes optimized acquisition parameters and real-time image processing algorithms. Air kerma (AK), dose area product (DAP) and acquisition time for digital fluoroscopy (DF) and digital subtraction angiography (DSA) were recorded. Body mass index was noted as well. DF image quality was assessed objectively by image noise measurements. DSA image quality was rated by two blinded, independent readers on a four-rank scale. Statistical differences were assessed with unpaired t tests and Wilcoxon rank-sum tests. There was no significant difference between the patients treated on the new (n = 36) and the old system (n = 18) regarding age (p = 0.10), BMI (p = 0.18), DF time (p = 0.35) and DSA time (p = 0.17). The new system significantly reduced the cumulative AK and DAP by 64 and 72%, respectively (median 0.58 Gy and 145.9 Gy*cm 2 vs. 1.62 Gy and 526.8 Gy*cm 2 , p < 0.01 for both). Specifically, DAP for DF and DSA decreased by 59% (75.3 vs. 181.9 Gy*cm 2 , p < 0.01) and 78% (67.6 vs. 312.2 Gy*cm 2 , p < 0.01), respectively. The new system achieved a significant decrease in DF image noise (p < 0.01) and a significantly better DSA image quality (p < 0.01). The new angiographic imaging system significantly improved image quality and reduced radiation exposure during UAE procedures.

  14. t-PA power-pulse spray with rheolytic mechanical thrombectomy using cross-sectional image-guided portal vein access for single setting treatment of subacute superior mesenteric vein thrombosis.

    Science.gov (United States)

    Syed, Mubin I; Gallagher, Ryan M; Ahmed, Rukan S; Shaikh, Azim; Roberto, Edward; Patel, Sumeet

    2018-01-01

    Isolated superior mesenteric vein (SMV) thrombosis is a rare but potentially fatal condition if untreated. Current treatments include transjugular or transhepatic approaches for rheolytic mechanical thrombectomy and subsequent infusions of thrombolytics. Tissue plasminogen activator (t-PA) power-pulse spray can provide benefit in a single setting without thrombolytic infusions. Computed tomography (CT) guidance for portal vein access is underutilized in this setting. Case 1 discusses acute SMV thrombosis treated with rheolytic mechanical thrombectomy alone using ultrasound guidance for portal vein access. Case 2 discusses subacute SMV thrombosis treated with the addition of t-PA power-pulse spray to the rheolytic mechanical thrombectomy, using CT guidance for portal vein access. With rheolytic mechanical thrombectomy alone, the patient in Case 1 had significant improvement in abdominal pain. Follow-up CT demonstrated no residual SMV thrombosis and the patient continued to do well in long-term follow-up. With the addition of t-PA power-pulse spray to rheolytic mechanical thrombectomy, the patient in Case 2 with subacute SMV thrombosis dramatically improved postprocedure with resolution of abdominal pain. Follow-up imaging demonstrated patency to the SMV and partial resolution of thrombus. The patient continued to do well at 2-year follow-up. Adding t-PA power-pulse spray to rheolytic mechanical thrombectomy can provide benefit in a single setting versus mechanical thrombectomy alone and prevent the need for subsequent infusions of thrombolytic therapy. CT guidance is a useful alternative of localization for portal vein access via the transhepatic route that is nonoperator-dependent and helpful in the case of obese patients.

  15. t-PA power-pulse spray with rheolytic mechanical thrombectomy using cross-sectional image-guided portal vein access for single setting treatment of subacute superior mesenteric vein thrombosis

    Directory of Open Access Journals (Sweden)

    Mubin I Syed

    2018-01-01

    Full Text Available Background: Isolated superior mesenteric vein (SMV thrombosis is a rare but potentially fatal condition if untreated. Current treatments include transjugular or transhepatic approaches for rheolytic mechanical thrombectomy and subsequent infusions of thrombolytics. Tissue plasminogen activator (t-PA power-pulse spray can provide benefit in a single setting without thrombolytic infusions. Computed tomography (CT guidance for portal vein access is underutilized in this setting. Materials and Methods: Case 1 discusses acute SMV thrombosis treated with rheolytic mechanical thrombectomy alone using ultrasound guidance for portal vein access. Case 2 discusses subacute SMV thrombosis treated with the addition of t-PA power-pulse spray to the rheolytic mechanical thrombectomy, using CT guidance for portal vein access. Results: With rheolytic mechanical thrombectomy alone, the patient in Case 1 had significant improvement in abdominal pain. Follow-up CT demonstrated no residual SMV thrombosis and the patient continued to do well in long-term follow-up. With the addition of t-PA power-pulse spray to rheolytic mechanical thrombectomy, the patient in Case 2 with subacute SMV thrombosis dramatically improved postprocedure with resolution of abdominal pain. Follow-up imaging demonstrated patency to the SMV and partial resolution of thrombus. The patient continued to do well at 2-year follow-up. Conclusions: Adding t-PA power-pulse spray to rheolytic mechanical thrombectomy can provide benefit in a single setting versus mechanical thrombectomy alone and prevent the need for subsequent infusions of thrombolytic therapy. CT guidance is a useful alternative of localization for portal vein access via the transhepatic route that is nonoperator-dependent and helpful in the case of obese patients.

  16. Xeroradiograph of the superior aerial structures

    International Nuclear Information System (INIS)

    Abreu Neto, B.P.; Broccoli Neto, J.; Forni, S.S.; Abilio, S.O.; Uemura, L.

    1987-01-01

    The tecnical procedures, image characteristics and main indications of the method are discussed and the application of the xeroradiography in the cervical region evaluation, including the pharyngeal and laryngeal structures are presented. (l.M.J.) [pt

  17. Which histological characteristics of basal cell carcinomas influence the quality of optical coherence tomography imaging?

    DEFF Research Database (Denmark)

    Mogensen, M.; Thrane, Lars; Jørgensen, Thomas Martini

    2009-01-01

    We explore how histopathology parameters influence OCT imaging of basal cell carcinomas (BCC) and address whether such parameters correlate with the quality of the recorded OCT images. Our results indicate that inflammation impairs OCT imaging and that sun-damaged skin can sometimes provide more ...... clear-cut images of skin cancer lesions using OCT imaging when compared to skin cancer surrounded by skin without sun-damage. ©2009 COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.......We explore how histopathology parameters influence OCT imaging of basal cell carcinomas (BCC) and address whether such parameters correlate with the quality of the recorded OCT images. Our results indicate that inflammation impairs OCT imaging and that sun-damaged skin can sometimes provide more...

  18. Imaging characteristics of two subtypes of congenital hemangiomas: rapidly involuting congenital hemangiomas and non-involuting congenital hemangiomas

    International Nuclear Information System (INIS)

    Gorincour, Guillaume; Rypens, Francoise; Garel, Laurent; Dubois, Josee; Kokta, Victor; Powell, Julie

    2005-01-01

    Common infantile hemangiomas (COMMON) occur in approximately 10% of infants by the age of 1 year, with a female predominance. Some hemangiomas can be fully developed at birth and are thus called congenital hemangiomas (CH). Within this population, two courses have been identified: rapidly involuting CH (RICH) and non-involuting CH (NICH). Little has been reported on the clinical prognosis and imaging features of these entities. To describe the imaging characteristics of two subtypes of CH, i.e. RICH and NICH, and to compare them with COMMON. We retrospectively gathered data on 26 children presenting with CH, i.e. lesions fully developed at birth. These lesions were divided into two groups according to the clinical course: suspected RICH (n=8) and suspected NICH (n=18). We used US, CT or MRI and angiography to identify the gross anatomy and structure and the vascularization. Imaging findings were compared with the clinical course and pathology results, when available. The imaging findings in these patients were compared retrospectively with those in 26 patients with COMMON randomly chosen from the database of our multidisciplinary clinic. When compared with COMMON imaging characteristics, NICH and RICH had distinctive features on US such as being heterogeneous (72% of NICH and 62.5% of RICH vs 42.3% of COMMON), visible vessels (72% of NICH and 62.5% of RICH vs 15.4% of COMMON), calcifications (17% of NICH and 37.5% of RICH vs no case of COMMON). On CT and/or MRI, we compared imaging features such as well-defined limits (67% of NICH and 60% of RICH vs 100% of COMMON), and fat stranding (29.4% of NICH and RICH vs 7.7% of COMMON). Distinctive imaging characteristics are observed in cases of CH with US findings of visible vessels and calcifications statistically significant. (orig.)

  19. Body image in patients with mental disorders : Characteristics, associations with diagnosis and treatment outcome

    NARCIS (Netherlands)

    Scheffers, Mia; van Busschbach, Jooske T; Bosscher, Ruud J; Aerts, Liza C; Wiersma, Durk; Schoevers, Robert A

    Objective: Despite the increasing recognition in clinical practice of body image problems in other than appearance related mental disorders, the question remains how aspects of body image are affected in different disorders. The aim of this study was to measure body image in patients with a variety

  20. Dynamic contrast-enhanced MR imaging in osteoid osteoma: relationships with clinical and CT characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Pottecher, P. [Hopital Lariboisiere, AP-HP, Department of Osteoarticular Radiology, Paris (France); Hopital du Bocage, Department of Vascular, Oncologic and Interventional Radiology, Dijon (France); Sibileau, E.; Hamze, B.; Parlier, C.; Laredo, J.D.; Bousson, V. [Hopital Lariboisiere, AP-HP, Department of Osteoarticular Radiology, Paris (France); Aho, S. [Hopital du Bocage, Hospital Hygiene and Epidemiology unit, Dijon (France)

    2017-07-15

    To correlate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) features to clinical and computed tomography (CT) morphological features of osteoid osteoma (OO). Our institutional review board approved this retrospective study, waiving the need for informed consent. We included the 102 patients treated with interstitial laser ablation for histologically documented OO at our institution in 2008-2013. DCE-MRI variables were the time-enhancement pattern and rising slope (Slope{sub rise}) and CT variables were the bone and segment involved (OO{sub bone} and OO{sub segment,} respectively), OO location relative to the native cortex (OO{sub cortex}), nidus surface area, vessel sign, and largest neighboring-vessel diameter (Dmax{sub vessel}). Descriptive statistics and correlations linking DCE-MRI findings to clinical and CT characteristics were computed. DCE-MRI showed early arterial peak enhancement in 95 (93%) cases, with a mean Slope{sub rise} of 9.30 ± 8.10. CT visualized a vessel sign in 84 (82%) cases with a mean Dmax{sub vessel} of 1.10 ± 0.60 mm. By univariate analysis, Slope{sub rise} correlated significantly with pain duration and Dmax{sub vessel} (r = 0.30, P = 0.003; and r = 0.22, P = 0.03; respectively). Analysis of variance showed that Slope{sub rise} correlated significantly with OO{sub bone} (P < 0.001), with a steeper slope for OOs located in short or flat bones. This study suggests more abundant vascularization of OOs with long-lasting pain and location on short or flat bones. (orig.)

  1. CT characteristics of Morel-Lavallee lesions: an under-recognized but significant finding in acute trauma imaging

    International Nuclear Information System (INIS)

    McKenzie, Gavin A.; Niederhauser, Blake D.; Collins, Mark S.; Howe, Benjamin M.

    2016-01-01

    To highlight the significance and imaging characteristics of Morel-Lavallee (ML) lesions, which have been well characterized on MRI, but are potentially under-recognized on CT. Twenty-eight Morel-Lavallee lesions were identified in 18 patients and were all clinically or surgically confirmed. Lesions were grouped into acute (<3 days), subacute (3-30 days), and chronic (>30 days) at the time of CT imaging. Charts were reviewed to gather patient characteristics, injury patterns, radiologist interpretation, treatment, and outcomes. Sixteen male and 2 female patients with a mean age of 50 years (range 19-80) at the date of their initial evaluation were identified. All patients had significant trauma that accounted for 28 ML lesions, all of which were in a characteristic subcutaneous location overlying the muscular fascial plane. Lesions on CT went through an evolution from hyperdense, poorly or moderately marginated without a pseudocapsule to being hypodense, with internal fat globules or septations and well marginated with a complete enhancing pseudocapsule. Only 1 (4 %) of the ML lesions was suggested and 7 (25 %) lesions were not commented on at all by the interpreting radiologist. Morel-Lavallee lesions are post-traumatic closed, internal, soft-tissue, degloving lesions that are potentially underrecognized on CT. Most acute ML lesions are nonspecific, resembling simple hematomas or contusions. ML lesions evolve as they age with subacute and chronic lesions demonstrating the known features described on MR imaging that should allow for an accurate imaging diagnosis. (orig.)

  2. CT characteristics of Morel-Lavallée lesions: an under-recognized but significant finding in acute trauma imaging.

    Science.gov (United States)

    McKenzie, Gavin A; Niederhauser, Blake D; Collins, Mark S; Howe, Benjamin M

    2016-08-01

    To highlight the significance and imaging characteristics of Morel-Lavallée (ML) lesions, which have been well characterized on MRI, but are potentially under-recognized on CT. Twenty-eight Morel-Lavallée lesions were identified in 18 patients and were all clinically or surgically confirmed. Lesions were grouped into acute (30 days) at the time of CT imaging. Charts were reviewed to gather patient characteristics, injury patterns, radiologist interpretation, treatment, and outcomes. Sixteen male and 2 female patients with a mean age of 50 years (range 19-80) at the date of their initial evaluation were identified. All patients had significant trauma that accounted for 28 ML lesions, all of which were in a characteristic subcutaneous location overlying the muscular fascial plane. Lesions on CT went through an evolution from hyperdense, poorly or moderately marginated without a pseudocapsule to being hypodense, with internal fat globules or septations and well marginated with a complete enhancing pseudocapsule. Only 1 (4 %) of the ML lesions was suggested and 7 (25 %) lesions were not commented on at all by the interpreting radiologist. Morel-Lavallée lesions are post-traumatic closed, internal, soft-tissue, degloving lesions that are potentially underrecognized on CT. Most acute ML lesions are nonspecific, resembling simple hematomas or contusions. ML lesions evolve as they age with subacute and chronic lesions demonstrating the known features described on MR imaging that should allow for an accurate imaging diagnosis.

  3. MR imaging characteristics of intracranial hemorrhage using gradient-echo signal acquisition at 1.5 T: Comparison with spin-echo imaging and clinical applications

    International Nuclear Information System (INIS)

    Atlas, S.W.; Grossman, R.I.; Gomori, J.M.; Hackney, D.B.; Goldberg, H.I.; Bilaniuk, L.T.; Zimmerman, R.A.

    1987-01-01

    Evolving paramagnetic blood-breakdown products create static local magnetic susceptibility gradients, which induce rapid phase dispersion on the basis of T2/sup */ shortening. The authors evaluated 30 patients with 50 separate hemorrhagic intracranial lesions with both spin-echo (SE) and gradient echo signal acquisition (GESA) MR imaging at 1.5 T. GESA sequences used repetition time (TR) of 200-750 msec, echo time (TE) of 50-80 msec, and flip angles of 10 0 to 15 0 to emphasize T2/sup */-based contributions to contrast. SE sequences in all cases utilized both short and long TR (600 and 2,500-3,000 msec), with TE of 20-120 msec. Advantages of GESA imaging with Long TE and short flip angles in the evaluation of intracranial hemorrhage include (1) increased sensitivity to susceptibility-induced phase loss from T2/sup */ shortening, resulting in detection of hemorrhagic lesions not seen on conventional long TR/long TE SE images, and (2) very rapid acquisition of images with T2/sup */-based contrast. Limitations of this sequence include (1) severe diamagnetic susceptibility-induced artifacts, especially near air-brain interfaces, which often obscure large portions of the brain and occasionally simulate serious pathology, (2) characteristic internal signal intensity patterns demonstrated by SE imaging, such as in evolving hematomas, occult vascular malformations, and hemorrhagic malignancies, are often obscured by marked hypointensity on GESA images, and (3) reduced signal-noise ratio. The authors conclude that, although images with marked sensitivity to T2/sup */ effects can be rapidly generated by GESA, there is only a limited role for this sequence when evaluating intracranial hemorrhage at 1.5 T, and, in fact, significant information is lost when compared to SE images

  4. Fourier power spectrum characteristics of face photographs: attractiveness perception depends on low-level image properties.

    Science.gov (United States)

    Menzel, Claudia; Hayn-Leichsenring, Gregor U; Langner, Oliver; Wiese, Holger; Redies, Christoph

    2015-01-01

    We investigated whether low-level processed image properties that are shared by natural scenes and artworks - but not veridical face photographs - affect the perception of facial attractiveness and age. Specifically, we considered the slope of the radially averaged Fourier power spectrum in a log-log plot. This slope is a measure of the distribution of special frequency power in an image. Images of natural scenes and artworks possess - compared to face images - a relatively shallow slope (i.e., increased high spatial frequency power). Since aesthetic perception might be based on the efficient processing of images with natural scene statistics, we assumed that the perception of facial attractiveness might also be affected by these properties. We calculated Fourier slope and other beauty-associated measurements in face images and correlated them with ratings of attractiveness and age of the depicted persons (Study 1). We found that Fourier slope - in contrast to the other tested image properties - did not predict attractiveness ratings when we controlled for age. In Study 2A, we overlaid face images with random-phase patterns with different statistics. Patterns with a slope similar to those in natural scenes and artworks resulted in lower attractiveness and higher age ratings. In Studies 2B and 2C, we directly manipulated the Fourier slope of face images and found that images with shallower slopes were rated as more attractive. Additionally, attractiveness of unaltered faces was affected by the Fourier slope of a random-phase background (Study 3). Faces in front of backgrounds with statistics similar to natural scenes and faces were rated as more attractive. We conclude that facial attractiveness ratings are affected by specific image properties. An explanation might be the efficient coding hypothesis.

  5. [68Ga]DOTATATE PET/MRI and [18F]FDG PET/CT are complementary and superior to diffusion-weighted MR imaging for radioactive-iodine-refractory differentiated thyroid cancer

    International Nuclear Information System (INIS)

    Vrachimis, Alexis; Stegger, Lars; Wenning, Christian; Noto, Benjamin; Konnert, Julia Renate; Riemann, Burkhard; Weckesser, Matthias; Burg, Matthias Christian; Allkemper, Thomas; Heindel, Walter; Schaefers, Michael

    2016-01-01

    The purpose of this study was to determine whether [ 68 Ga]DOTATATE PET/MRI with diffusion-weighted imaging (DWI) can replace or complement [ 18 F]FDG PET/CT in patients with radioactive-iodine (RAI)-refractory differentiated thyroid cancer (DTC). The study population comprised 12 patients with elevated thyroglobulin and a negative RAI scan after thyroidectomy and RAI remnant ablation who underwent both [ 18 F]FDG PET/CT and [ 68 Ga]DOTATATE PET/MRI within 8 weeks of each other. The presence of recurrent cancer was evaluated on a per-patient, per-organ and per-lesion basis. Histology, and prior and follow-up examinations served as the standard of reference. Recurrent or metastatic tumour was confirmed in 11 of the 12 patients. [ 68 Ga]DOTATATE PET(/MRI) correctly identified the tumour burden in all 11 patients, whereas in one patient local relapse was missed by [ 18 F]FDG PET/CT. In the lesion-based analysis, overall lesion detection rates were 79/85 (93 %), 69/85 (81 %) and 27/82 (33 %) for [ 18 F]FDG PET/CT, [ 68 Ga]DOTATATE PET/MRI and DWI, respectively. [ 18 F]FDG PET(/CT) was superior to [ 68 Ga]DOTATATE PET(/MRI) in the overall evaluation and in the detection of pulmonary metastases. In the detection of extrapulmonary metastases, [ 68 Ga]DOTATATE PET(/MRI) showed a higher sensitivity than [ 18 F]FDG PET(/CT), at the cost of lower specificity. DWI achieved only poor sensitivity and was significantly inferior to [ 18 F]FDG PET in the lesion-based evaluation in the detection of both extrapulmonary and pulmonary metastases. [ 18 F]FDG PET/CT was more sensitive than [ 68 Ga]DOTATATE PET/MRI in the evaluation of RAI-refractory DTC, mostly because of its excellent ability to detect lung metastases. In the evaluation of extrapulmonary lesions, [ 68 Ga]DOTATATE PET(/MRI) was more sensitive and [ 18 F]FDG PET(/CT) more specific. Furthermore, DWI did not provide additional information and cannot replace [ 18 F]FDG PET for postoperative monitoring of patients with

  6. Gastrin-releasing peptide receptor-based targeting using bombesin analogues is superior to metabolism-based targeting using choline for in vivo imaging of human prostate cancer xenografts

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Rogier P.J. [Erasmus MC, Department of Nuclear Medicine, Rotterdam (Netherlands); Erasmus MC, Department of Urology, Rotterdam (Netherlands); Weerden, W.M. van; Bangma, C.H.; Reneman, S. [Erasmus MC, Department of Urology, Rotterdam (Netherlands); Krenning, E.P.; Berndsen, S.; Grievink-de Ligt, C.H.; Groen, H.C.; Blois, E. de; Breeman, W.A.P.; Jong, M. de [Erasmus MC, Department of Nuclear Medicine, Rotterdam (Netherlands)

    2011-07-15

    Prostate cancer (PC) is a major health problem. Overexpression of the gastrin-releasing peptide receptor (GRPR) in PC, but not in the hyperplastic prostate, provides a promising target for staging and monitoring of PC. Based on the assumption that cancer cells have increased metabolic activity, metabolism-based tracers are also being used for PC imaging. We compared GRPR-based targeting using the {sup 68}Ga-labelled bombesin analogue AMBA with metabolism-based targeting using {sup 18}F-methylcholine ({sup 18}F-FCH) in nude mice bearing human prostate VCaP xenografts. PET and biodistribution studies were performed with both {sup 68}Ga-AMBA and {sup 18}F-FCH in all VCaP tumour-bearing mice, with PC-3 tumour-bearing mice as reference. Scanning started immediately after injection. Dynamic PET scans were reconstructed and analysed quantitatively. Biodistribution of tracers and tissue uptake was expressed as percent of injected dose per gram tissue (%ID/g). All tumours were clearly visualized using {sup 68}Ga-AMBA. {sup 18}F-FCH showed significantly less contrast due to poor tumour-to-background ratios. Quantitative PET analyses showed fast tumour uptake and high retention for both tracers. VCaP tumour uptake values determined from PET at steady-state were 6.7 {+-} 1.4%ID/g (20-30 min after injection, N = 8) for {sup 68}Ga-AMBA and 1.6 {+-} 0.5%ID/g (10-20 min after injection, N = 8) for {sup 18}F-FCH, which were significantly different (p <0.001). The results in PC-3 tumour-bearing mice were comparable. Biodistribution data were in accordance with the PET results showing VCaP tumour uptake values of 9.5 {+-} 4.8%ID/g (N = 8) for {sup 68}Ga-AMBA and 2.1 {+-} 0.4%ID/g (N = 8) for {sup 18}F-FCH. Apart from the GRPR-expressing organs, uptake in all organs was lower for {sup 68}Ga-AMBA than for {sup 18}F-FCH. Tumour uptake of {sup 68}Ga-AMBA was higher while overall background activity was lower than observed for {sup 18}F-FCH in the same PC-bearing mice. These results

  7. Imaging Characteristics and Prevalence of Pancreatic Carcinoma in Kosovo During 2011-2015 - Diagnostic Method as Choice

    OpenAIRE

    Dedushi, Kreshnike; Kabashi, Serbeze; Mucaj, Sefedin; Hasbahta, Gazmed; Ramadani, Naser; Hoxhaj, Astrit

    2016-01-01

    Introduction: Pancreatic cancer is the 10thmost common malignancy and the 4thlargest cancer killer in adults. Aim: The purpose of this paper is to evaluate the number of cases presented with pancreatic carcinoma during the years 2011-2015, our experience of the imaging characteristics of pancreatic carcinoma. We evaluated prevalence of the pancreatic cancers, distant metastases and other local infiltration signs among the total cases of the pancreatic cancers diagnosed in the University Clini...

  8. Facial Nerve Paralysis due to a Pleomorphic Adenoma with the Imaging Characteristics of a Facial Nerve Schwannoma

    OpenAIRE

    Nader, Marc-Elie; Bell, Diana; Sturgis, Erich M.; Ginsberg, Lawrence E.; Gidley, Paul W.

    2014-01-01

    Background Facial nerve paralysis in a patient with a salivary gland mass usually denotes malignancy. However, facial paralysis can also be caused by benign salivary gland tumors. Methods We present a case of facial nerve paralysis due to a benign salivary gland tumor that had the imaging characteristics of an intraparotid facial nerve schwannoma. Results The patient presented to our clinic 4 years after the onset of facial nerve paralysis initially diagnosed as Bell palsy. Computed tomograph...

  9. Clinical significance of creative 3D-image fusion across multimodalities [PET + CT + MR] based on characteristic coregistration

    International Nuclear Information System (INIS)

    Peng, Matthew Jian-qiao; Ju Xiangyang; Khambay, Balvinder S.; Ayoub, Ashraf F.; Chen, Chin-Tu; Bai Bo

    2012-01-01

    Objective: To investigate a registration approach for 2-dimension (2D) based on characteristic localization to achieve 3-dimension (3D) fusion from images of PET, CT and MR one by one. Method: A cubic oriented scheme of“9-point and 3-plane” for co-registration design was verified to be geometrically practical. After acquisiting DICOM data of PET/CT/MR (directed by radiotracer 18 F-FDG etc.), through 3D reconstruction and virtual dissection, human internal feature points were sorted to combine with preselected external feature points for matching process. By following the procedure of feature extraction and image mapping, “picking points to form planes” and “picking planes for segmentation” were executed. Eventually, image fusion was implemented at real-time workstation mimics based on auto-fuse techniques so called “information exchange” and “signal overlay”. Result: The 2D and 3D images fused across modalities of [CT + MR], [PET + MR], [PET + CT] and [PET + CT + MR] were tested on data of patients suffered from tumors. Complementary 2D/3D images simultaneously presenting metabolic activities and anatomic structures were created with detectable-rate of 70%, 56%, 54% (or 98%) and 44% with no significant difference for each in statistics. Conclusion: Currently, based on the condition that there is no complete hybrid detector integrated of triple-module [PET + CT + MR] internationally, this sort of multiple modality fusion is doubtlessly an essential complement for the existing function of single modality imaging.

  10. How customers construct corporate social responsibility images: Testing the moderating role of demographic characteristics

    Directory of Open Access Journals (Sweden)

    Andrea Pérez

    2015-04-01

    Full Text Available This paper discusses the formation process of CSR images from a customer perspective. It analyses the influence of company-CSR coherence, motivational attribution and corporate credibility in the way customers evaluate CSR images in the banking industry. It also describes the impact of customer gender, age and educational level on the formation of CSR images. Results show that CSR images are based on customer perceptions of the company-CSR coherence, the attribution of altruistic motivations and corporate credibility when developing CSR initiatives. The findings also demonstrate that gender, age and educational level do not allow identifying differences in the way customers construct CSR images. Thus, they are not useful in segmenting customers for the design of better CSR and communication strategies.

  11. SU-E-J-23: Characteristics of X-Rays From ExacTrac and Patient Dose From Imaging Procedures

    Energy Technology Data Exchange (ETDEWEB)

    Ding, G [Vanderbilt University, Nashville, TN (United States)

    2015-06-15

    Purpose: The purpose of this investigation is 1) provide the beam characteristics of x-rays produced by a Novalis TX ExacTrac system; 2) present a method to commission such beams, 3) present radiation dose to patients resulting from the imaging procedures. Methods: The Monte Carlo simulations were used to obtain the characteristics of kV beams and validated by measurements. The calculated beam HVLs, profiles and depth-dose curves were benchmarked against measurements. Twelve different image acquisition protocols were studied. The x-ray tube voltage ranges from 70 - 145 kV and milliampere-second (mAs) ranges from 8 - 80 mAs depending on the selection of Cranium, Head & Neck, Thorax or Abdomen imaging protocols. The beam output of each image acquisition protocol was determined by using an ionization chamber. The air kerma calibration factors of the ion chamber were obtained from an Accredited Dosimetry Calibration Laboratory for specified HVLs. Results: The agreements between measured and simulated results were within the uncertainties for HVLs, dose profiles and depth-dose curves. When %dd was normalized at 1 cm depth, its values at depth of 5 cm ranged from 45% to 66% of in water for kV beams range from 70 kVp to 145 kVp respectively. For head images, a typical dose to eye resulting from single projection ranged from 0.008 cGy to 0.025 cGy depending on the cranial image protocols selected. For a single pelvic image the skin dose could reach up to 0.1 cGy from an abdominal protocol. Conclusion: Although multiple pairs of x-ray images are commonly acquired during a daily patient treatment, the imaging doses to patients resulting from the sum of these projected x-rays are generally much less than 0.5 cGy. The knowledge obtained from this investigation can be used to estimate the image dose and optimize the used of the system.

  12. Superior ophthalmic vein enlargement and increased muscle index in dysthyroid optic neuropathy.

    Science.gov (United States)

    Lima, Breno da Rocha; Perry, Julian D

    2013-01-01

    To compare superior ophthalmic vein diameter and extraocular muscle index in patients with thyroid eye disease with or without optic neuropathy. High-resolution CT scan images of 40 orbits of 20 patients with history of thyroid eye disease (with or without optic neuropathy), who underwent orbital decompression surgery from January 2007 to November 2009, were retrospectively reviewed. Superior ophthalmic vein diameter was measured in coronal and axial planes. Extraocular muscle index was calculated according to the method proposed by Barrett et al. The clinical diagnosis of optic neuropathy was based on characteristic signs that included afferent pupillary defect, decreased visual acuity, visual field defects, and dyschromatopsia. Orbits were divided in 2 groups based on presence or absence of optic neuropathy. Superior ophthalmic vein diameter was significantly higher in orbits with concomitant optic neuropathy (mean 2.4 ± 0.4mm, p optic neuropathy (mean 57.9% ± 5.7%, p = 0.0002). Muscle index greater than 50% was present in all patients with dysthyroid optic neuropathy. This study suggests that patients with thyroid eye disease with enlarged superior ophthalmic vein and increased extraocular muscle index are more likely to have concomitant optic neuropathy.

  13. Confocal stereology and image analysis: methods for estimating geometrical characteristics of cells and tissues from three-dimensional confocal images

    Czech Academy of Sciences Publication Activity Database

    Kubínová, Lucie; Janáček, Jiří; Karen, Petr; Radochová, Barbora; Difato, Francesco; Krekule, Ivan

    2004-01-01

    Roč. 53, Suppl.1 (2004), s. S47-S55 ISSN 0862-8408 R&D Projects: GA ČR GA304/01/0257; GA ČR GA310/02/1470; GA AV ČR KJB6011309; GA AV ČR KJB5039302 Grant - others:SI - CZ(CZ) KONTAKT 001/2001 Institutional research plan: CEZ:AV0Z5011922 Keywords : confocal microscopy * image analysis * stereology Subject RIV: EA - Cell Biology Impact factor: 1.140, year: 2004

  14. Ruptured superior gluteal artery pseudoaneurysm with hemorrhagic shock: Case report

    Directory of Open Access Journals (Sweden)

    Kerem Seref Corbacioglu

    2016-03-01

    Full Text Available Pseudoaneurysm of the superior gluteal artery (SGA is very rare and the most common causes are blunt or penetrating pelvic traumas. Although pseudoaneurysm can be asymptomatic at the time of initial trauma, it can be symptomatic weeks, months, even years after initial trauma. We present a case of a ruptured superior gluteal artery pseudoaneurysm with hemorrhagic shock twenty days after a bomb injury in the Syria civil war. In addition, we review the anatomy of the SGA, clinical presentation and pitfalls of pseudoaneurysm, and imaging and treatment options. Keywords: Pseudoaneurysm, Superior gluteal artery, Pitfall, Angiography

  15. Temporal characteristics of radiologists’ and novices’ lesion detection in viewing medical images presented rapidly and sequentially

    Directory of Open Access Journals (Sweden)

    Ryoichi Nakashima

    2016-10-01

    Full Text Available Although viewing multiple stacks of medical images presented on a display is a relatively new but useful medical task, little is known about this task. Particularly, it is unclear how radiologists search for lesions in this type of image reading. When viewing cluttered and dynamic displays, continuous motion itself does not capture attention. Thus, it is effective for the target detection that observers’ attention is captured by the onset signal of a suddenly appearing target among the continuously moving distractors (i.e., a passive viewing strategy. This can be applied to stack viewing tasks, because lesions often show up as transient signals in medical images which are sequentially presented simulating a dynamic and smoothly transforming image progression of organs. However, it is unclear whether observers can detect a target when the target appears at the beginning of a sequential presentation where the global apparent motion onset signal (i.e., signal of the initiation of the apparent motion by sequential presentation occurs. We investigated the ability of radiologists to detect lesions during such tasks by comparing the performances of radiologists and novices. Results show that overall performance of radiologists is better than novices. Furthermore, the temporal locations of lesions in CT image sequences, i.e., when a lesion appears in an image sequence, does not affect the performance of radiologists, whereas it does affect the performance of novices. Results indicate that novices have greater difficulty in detecting a lesion appearing early than late in the image sequence. We suggest that radiologists have other mechanisms to detect lesions in medical images with little attention which novices do not have. This ability is critically important when viewing rapid sequential presentations of multiple CT images, such as stack viewing tasks.

  16. Pulmonary dynamics and functional imaging with krypton-81m as related to generator delivery characteristics

    International Nuclear Information System (INIS)

    Kaplan, E.

    1985-01-01

    Krypton-81m supplied from a generator by continuous elution with air is used with a gamma-camera computer system to produce a sequence of images from multiple breaths, which reconstructed the time-activity images of the breathing human lung. Functional images are produced by subsequent derivation to show specific variables of the dynamic sequences. The dynamic, quantitative, and regional aspects of the respiratory cycle are thus made available in a single study. The need for the delivery of a constant ratio of /sub 81m/Kr to air is required to accurately produce these various studies

  17. FDTD parallel computational analysis of grid-type scattering filter characteristics for medical X-ray image diagnosis

    International Nuclear Information System (INIS)

    Takahashi, Koichi; Miyazaki, Yasumitsu; Goto, Nobuo

    2007-01-01

    X-ray diagnosis depends on the intensity of transmitted and scattered waves in X-ray propagation in biomedical media. X-ray is scattered and absorbed by tissues, such as fat, bone and internal organs. However, image processing for medical diagnosis, based on the scattering and absorption characteristics of these tissues in X-ray spectrum is not so much studied. To obtain precise information of tissues in a living body, the accurate characteristics of scattering and absorption are required. In this paper, X-ray scattering and absorption in biomedical media are studied using 2-dimensional finite difference time domain (FDTD) method. In FDTD method, the size of analysis space is very limited by the performance of available computers. To overcome this limitation, parallel and successive FDTD method is introduced. As a result of computer simulation, the amplitude of transmitted and scattered waves are presented numerically. The fundamental filtering characteristics of grid-type filter are also shown numerically. (author)

  18. Eutrophication monitoring for Lake Superior's Chequamegon ...

    Science.gov (United States)

    A priority for the Lake Superior CSMI was to identify susceptible nearshore eutrophication areas. We developed an integrated sampling design to collect baseline data for Lake Superior’s Chequamegon Bay to understand how nearshore physical processes and tributary loading relate to observed chlorophyll concentrations. Sampling included ship-based water samples combined with vertical CTD casts, continuous in situ towing and data collected from an autonomous underwater glider. Sampling was conducted during June, July and September. The glider collected regional data as part of three extended missions in Lake Superior over the same periods. During the study, two significant storm events impacted the western end of Lake Superior; the first occurred during July 11-12, with 8-10 inches of rain in 24hrs, and the second on July 21 with winds in excess of 161 km/h. Using GIS software, we organized these diverse temporal data sets along a continuous time line with temporally coincident Modis Satellite data to visualize surface sediment plumes in relation to water quality measurements. Preliminary results suggest that both events impacted regional water quality, and that nearshore physical forces (upwelling and currents) influenced the spatial variability. Results comparing in situ measures with remotely sensed images will be discussed. not applicable

  19. The use of global image characteristics for neural network pattern recognitions

    Science.gov (United States)

    Kulyas, Maksim O.; Kulyas, Oleg L.; Loshkarev, Aleksey S.

    2017-04-01

    The recognition system is observed, where the information is transferred by images of symbols generated by a television camera. For descriptors of objects the coefficients of two-dimensional Fourier transformation generated in a special way. For solution of the task of classification the one-layer neural network trained on reference images is used. Fast learning of a neural network with a single neuron calculation of coefficients is applied.

  20. Performance characteristics of UV imaging instrumentation for diffusion, dissolution and release testing studies

    DEFF Research Database (Denmark)

    Jensen, Sabrine S; Jensen, Henrik; Goodall, David M

    2016-01-01

    UV imaging is capable of providing spatially and temporally resolved absorbance measurements, which is highly beneficial in drug diffusion, dissolution and release testing studies. For optimal planning and design of experiments, knowledge about the capabilities and limitations of the imaging syst...... mainly to depend on collimation of light, the light path, the positioning of the object relative to the line of 100μm fibres which forms the light source, and the distance of the object from the sensor surface....

  1. Measurement of blood flow in the superior sagittal sinus in healthy volunteers, and in patients with normal pressure hydrocephalus and idiopathic intracranial hypertension with phase-contrast cine MR imaging

    DEFF Research Database (Denmark)

    Gideon, P; Thomsen, C; Gjerris, F

    1996-01-01

    PURPOSE: To measure blood flow and velocity in the superior sagittal ++sinus. MATERIAL AND METHODS: MR velocity mapping was used to examine 14 healthy volunteers, 15 patients with normal pressure hydrocephalus (NPH), 3 patients with high pressure hydrocephalus (HPH), and 11 patients with idiopathic...

  2. ANALYZING SPECTRAL CHARACTERISTICS OF SHADOW AREA FROM ADS-40 HIGH RADIOMETRIC RESOLUTION AERIAL IMAGES

    Directory of Open Access Journals (Sweden)

    Y.-T. Hsieh

    2016-06-01

    Full Text Available The shadows in optical remote sensing images are regarded as image nuisances in numerous applications. The classification and interpretation of shadow area in a remote sensing image are a challenge, because of the reduction or total loss of spectral information in those areas. In recent years, airborne multispectral aerial image devices have been developed 12-bit or higher radiometric resolution data, including Leica ADS-40, Intergraph DMC. The increased radiometric resolution of digital imagery provides more radiometric details of potential use in classification or interpretation of land cover of shadow areas. Therefore, the objectives of this study are to analyze the spectral properties of the land cover in the shadow areas by ADS-40 high radiometric resolution aerial images, and to investigate the spectral and vegetation index differences between the various shadow and non-shadow land covers. According to research findings of spectral analysis of ADS-40 image: (i The DN values in shadow area are much lower than in nonshadow area; (ii DN values received from shadowed areas that will also be affected by different land cover, and it shows the possibility of land cover property retrieval as in nonshadow area; (iii The DN values received from shadowed regions decrease in the visible band from short to long wavelengths due to scattering; (iv The shadow area NIR of vegetation category also shows a strong reflection; (v Generally, vegetation indexes (NDVI still have utility to classify the vegetation and non-vegetation in shadow area. The spectral data of high radiometric resolution images (ADS-40 is potential for the extract land cover information of shadow areas.

  3. Costs, charges, and revenues for hospital diagnostic imaging procedures: differences by modality and hospital characteristics.

    Science.gov (United States)

    Sistrom, Christopher Lee; McKay, Niccie L

    2005-06-01

    This study examined financial data reported by Florida hospitals concerning costs, charges, and revenues related to imaging services. Financial reports to the Florida Hospital Uniform Reporting System by all licensed acute care facilities for fiscal year 2002 were used to calculate four financial indices on a per procedure basis. These included charge, net revenue, operating expense (variable cost), and contribution margin. Analysis, stratified by cost center (imaging modality), tested the effects of bed size, ownership, teaching status, and urban or rural status on the four indices. The mean operating expense and charge per procedure were as follows: computed tomography (CT): $51 and $1565; x-ray and ultrasound: $55 and $410; nuclear medicine (NM): $135 and $1138; and magnetic resonance imaging (MRI): $165 and $2048. With all four modalities, for-profit hospitals had higher charges than not-for-profit and public facilities. Excepting NM, however, the difference by ownership disappeared when considering net revenue. Operating expense did not differ by ownership type or bed size. Operating expense (variable cost) per procedure is considerably lower for CT than for MRI. Consequently, when diagnostically equivalent, CT is preferable to MRI in terms of costs for hospitals. If the cost structure of nonhospital imaging is at all similar to hospitals, the profit potential for performing CT and MRI seems to be substantial, which has relevance to the issue of imaging self-referral.

  4. The maximum likelihood estimator method of image reconstruction: Its fundamental characteristics and their origin

    International Nuclear Information System (INIS)

    Llacer, J.; Veklerov, E.

    1987-05-01

    We review our recent work characterizing the image reconstruction properties of the MLE algorithm. We studied its convergence properties and confirmed the onset of image deterioration, which is a function of the number of counts in the source. By modulating the weight given to projection tubes with high numbers of counts with respect to those with low numbers of counts in the reconstruction process, we have confirmed that image deterioration is due to an attempt by the algorithm to match projection data tubes with high numbers of counts too closely to the iterative image projections. We developed a stopping rule for the algorithm that tests the hypothesis that a reconstructed image could have given the initial projection data in a manner consistent with the underlying assumption of Poisson distributed variables. The rule was applied to two mathematically generated phantoms with success and to a third phantom with exact (no statistical fluctuations) projection data. We conclude that the behavior of the target functions whose extrema are sought in iterative schemes is more important in the early stages of the reconstruction than in the later stages, when the extrema are being approached but with the Poisson nature of the measurement. 11 refs., 14 figs

  5. CT and MR Imaging Characteristics of Intravestibular and Cerebellopontine Angle Lipoma

    International Nuclear Information System (INIS)

    Buyukkaya, Ramazan; Buyukkaya, Ayla; Ozturk, Beyhan; Yaman, Huseyin; Belada, Abdullah

    2014-01-01

    Intracranial lipoma is an uncommon entity. A rare type of tumor in the internal auditory canal (IAC) and the cerebellopontine angle (CPA) is lipoma. There are a few case reports in the literature related to intravestibular lipoma. Herein, we report a case of lipomas within the cerebellopontine angle and vestibule of the inner ear in a patient with tinnitus and dizziness. The patient was evaluated with a 1.5 T magnetic resonance imaging (MRI) system. MRI and CT showed the masses in the left CPA and the left IAC. These lesions were hyperintense on both T1- and T2 weighted images and showed no enhancement after gadolinium administration. Conservative management was suggested. Histopathological diagnosis is rarely necessary with the widespread use of magnetic resonance imaging. Considering significant morbidity during resection, conservative follow-up is the best approach for CPA and IAC lipoma

  6. CT and MR Imaging Characteristics of Intravestibular and Cerebellopontine Angle Lipoma

    Energy Technology Data Exchange (ETDEWEB)

    Buyukkaya, Ramazan [Department of Radiology, School of Medicine, Duzce University, Duzce (Turkey); Buyukkaya, Ayla [Department of Radiology, Duzce Ataturk Government Hospital, Duzce (Turkey); Ozturk, Beyhan [Department of Radiology, School of Medicine, Duzce University, Duzce (Turkey); Yaman, Huseyin; Belada, Abdullah [Department of Ear Nose and Throat, School of Medicine, Duzce University, Duzce (Turkey)

    2014-06-15

    Intracranial lipoma is an uncommon entity. A rare type of tumor in the internal auditory canal (IAC) and the cerebellopontine angle (CPA) is lipoma. There are a few case reports in the literature related to intravestibular lipoma. Herein, we report a case of lipomas within the cerebellopontine angle and vestibule of the inner ear in a patient with tinnitus and dizziness. The patient was evaluated with a 1.5 T magnetic resonance imaging (MRI) system. MRI and CT showed the masses in the left CPA and the left IAC. These lesions were hyperintense on both T1- and T2 weighted images and showed no enhancement after gadolinium administration. Conservative management was suggested. Histopathological diagnosis is rarely necessary with the widespread use of magnetic resonance imaging. Considering significant morbidity during resection, conservative follow-up is the best approach for CPA and IAC lipoma.

  7. Pulmonary cryptococcosis in rheumatoid arthritis (RA) patients: Comparison of imaging characteristics among RA, acquired immunodeficiency syndrome, and immunocompetent patients

    International Nuclear Information System (INIS)

    Yanagawa, Noriyo; Sakai, Fumikazu; Takemura, Tamiko; Ishikawa, Satoru; Takaki, Yasunobu; Hishima, Tsunekazu; Kamata, Noriko

    2013-01-01

    Purpose: The imaging characteristics of cryptococcosis in rheumatoid arthritis (RA) patients were analyzed by comparing them with those of acquired immunodeficiency syndrome (AIDS) and immunocompetent patients, and the imaging findings were correlated with pathological findings. Methods: Two radiologists retrospectively compared the computed tomographic (CT) findings of 35 episodes of pulmonary cryptococcosis in 31 patients with 3 kinds of underlying states (10 RA, 12 AIDS, 13 immunocompetent), focusing on the nature, number, and distribution of lesions. The pathological findings of 18 patients (8 RA, 2 AIDS, 8 immunocompetent) were analyzed by two pathologists, and then correlated with imaging findings. Results: The frequencies of consolidation and ground glass attenuation (GGA) were significantly higher, and the frequency of peripheral distribution was significantly lower in the RA group than in the immunocompetent group. Peripheral distribution was less common and generalized distribution was more frequent in the RA group than in the AIDS group. The pathological findings of the AIDS and immunocompetent groups reflected their immune status: There was lack of a granuloma reaction in the AIDS group, and a complete granuloma reaction in the immunocompetent group, while the findings of the RA group varied, including a complete granuloma reaction, a loose granuloma reaction and a hyper-immune reaction. Cases with the last two pathologic findings were symptomatic and showed generalized or central distribution on CT. Conclusion: Cryptococcosis in the RA group showed characteristic radiological and pathological findings compared with the other 2 groups

  8. Spatial frequency characteristics at image decision-point locations for observers with different radiological backgrounds in lung nodule detection

    Science.gov (United States)

    Pietrzyk, Mariusz W.; Manning, David J.; Dix, Alan; Donovan, Tim

    2009-02-01

    Aim: The goal of the study is to determine the spatial frequency characteristics at locations in the image of overt and covert observers' decisions and find out if there are any similarities in different observers' groups: the same radiological experience group or the same accuracy scored level. Background: The radiological task is described as a visual searching decision making procedure involving visual perception and cognitive processing. Humans perceive the world through a number of spatial frequency channels, each sensitive to visual information carried by different spatial frequency ranges and orientations. Recent studies have shown that particular physical properties of local and global image-based elements are correlated with the performance and the level of experience of human observers in breast cancer and lung nodule detections. Neurological findings in visual perception were an inspiration for wavelet applications in vision research because the methodology tries to mimic the brain processing algorithms. Methods: The wavelet approach to the set of postero-anterior chest radiographs analysis has been used to characterize perceptual preferences observers with different levels of experience in the radiological task. Psychophysical methodology has been applied to track eye movements over the image, where particular ROIs related to the observers' fixation clusters has been analysed in the spaces frame by Daubechies functions. Results: Significance differences have been found between the spatial frequency characteristics at the location of different decisions.

  9. Pulmonary cryptococcosis in rheumatoid arthritis (RA) patients: Comparison of imaging characteristics among RA, acquired immunodeficiency syndrome, and immunocompetent patients

    Energy Technology Data Exchange (ETDEWEB)

    Yanagawa, Noriyo, E-mail: noriyo_yana@ybb.ne.jp [Departments of Radiology, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, 3-8-22, Honkomagome, Bunkyo-ku, Tokyo 113-8677 (Japan); Sakai, Fumikazu [Department of Diagnostic Radiology, Saitama Medical University International Medical Center, 1397-1 Yamane, Hidaka-shi, Saitama 350-1298 (Japan); Takemura, Tamiko [Department of Pathology, Japanese Red Cross Medical Center, 4-1-22 Hiroo, Shibuya-ku, Tokyo 150-8935 (Japan); Ishikawa, Satoru [Department of Respiratory Medicine, National Hospital Organization Chiba-East-Hospital, 673 Nitona-cho, Chuo-ku, Chiba-shi, Chiba 260-8712 (Japan); Takaki, Yasunobu [Departments of Radiology, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, 3-8-22, Honkomagome, Bunkyo-ku, Tokyo 113-8677 (Japan); Hishima, Tsunekazu [Department of Pathology, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, 3-8-22, Honkomagome, Bunkyo-ku, Tokyo 113-8677 (Japan); Kamata, Noriko [Departments of Radiology, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, 3-8-22, Honkomagome, Bunkyo-ku, Tokyo 113-8677 (Japan)

    2013-11-01

    Purpose: The imaging characteristics of cryptococcosis in rheumatoid arthritis (RA) patients were analyzed by comparing them with those of acquired immunodeficiency syndrome (AIDS) and immunocompetent patients, and the imaging findings were correlated with pathological findings. Methods: Two radiologists retrospectively compared the computed tomographic (CT) findings of 35 episodes of pulmonary cryptococcosis in 31 patients with 3 kinds of underlying states (10 RA, 12 AIDS, 13 immunocompetent), focusing on the nature, number, and distribution of lesions. The pathological findings of 18 patients (8 RA, 2 AIDS, 8 immunocompetent) were analyzed by two pathologists, and then correlated with imaging findings. Results: The frequencies of consolidation and ground glass attenuation (GGA) were significantly higher, and the frequency of peripheral distribution was significantly lower in the RA group than in the immunocompetent group. Peripheral distribution was less common and generalized distribution was more frequent in the RA group than in the AIDS group. The pathological findings of the AIDS and immunocompetent groups reflected their immune status: There was lack of a granuloma reaction in the AIDS group, and a complete granuloma reaction in the immunocompetent group, while the findings of the RA group varied, including a complete granuloma reaction, a loose granuloma reaction and a hyper-immune reaction. Cases with the last two pathologic findings were symptomatic and showed generalized or central distribution on CT. Conclusion: Cryptococcosis in the RA group showed characteristic radiological and pathological findings compared with the other 2 groups.

  10. Characteristic MR and CT imaging findings of hepatobiliary paragonimiasis and their pathologic correlations

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Chunyan; Hu, Yajun; Chen, Weixia [Dept of Radiology, West China Hospital of Sichuan Univ., Sichuan (China)], e-mail: wxchen25@126.com

    2012-06-15

    Background: Hepatobiliary paragonimiasis (HP) is not commonly encountered and may be confused with hepatobiliary tumors; however, computed tomography (CT) and magnetic resonance imaging (MRI) features of HP allow this entity to be distinguished from other diseases. Purpose: To present the CT and MRI findings in patients with HP and to describe some specific imaging findings along with their pathological correlations. Material and Methods: Imaging and clinical findings of 21 patients (9 boys/men and 12 girls/women; age range 3-67 years; mean age 40 years) who were diagnosed with HP were retrospectively evaluated. Among these patients, 16 underwent CT examination only, two had MR examination only, and three underwent both CT and MR. All patients underwent surgery, and the HP diagnosis was confirmed by the surgical and histopathologic results. Results: Chronic abdominal pain or back pain was reported by 14 patients, severe abdominal pain with acute onset was reported by one patient, and six patients were asymptomatic and were discovered incidentally. Peripheral eosinophilia was present in 14 patients (14/21, 66.7%), and abnormal liver function tests were found in 16 patients (16/21, 76.2%). Of the 19 patients who underwent CT imaging, 17 patients showed multiple mixed hypodense lesions or multiple cysts with inlaying septation with separate irregular rims or circular enhancement on post-contrast CT images. Tunnel-shaped micro abscesses and necrotic cavities were found in the lesions of 12 of those 17 patients. The other two patients showed smaller cystic masses. MRI showed faveolate T1 hypointense and T2 hyperintense areas in the liver parenchyma with rim or peripheral enhancement. Nodular or circular hyperintense materials were found scattered in the lesions on T1-weighted imaging. Conclusion: CT and MRI can reveal the radiological-pathological features of HP. Together with laboratory findings, MRI and CT findings may provide diagnostic clues, especially in endemic

  11. Characteristic MR and CT imaging findings of hepatobiliary paragonimiasis and their pathologic correlations

    International Nuclear Information System (INIS)

    Lu, Chunyan; Hu, Yajun; Chen, Weixia

    2012-01-01

    Background: Hepatobiliary paragonimiasis (HP) is not commonly encountered and may be confused with hepatobiliary tumors; however, computed tomography (CT) and magnetic resonance imaging (MRI) features of HP allow this entity to be distinguished from other diseases. Purpose: To present the CT and MRI findings in patients with HP and to describe some specific imaging findings along with their pathological correlations. Material and Methods: Imaging and clinical findings of 21 patients (9 boys/men and 12 girls/women; age range 3-67 years; mean age 40 years) who were diagnosed with HP were retrospectively evaluated. Among these patients, 16 underwent CT examination only, two had MR examination only, and three underwent both CT and MR. All patients underwent surgery, and the HP diagnosis was confirmed by the surgical and histopathologic results. Results: Chronic abdominal pain or back pain was reported by 14 patients, severe abdominal pain with acute onset was reported by one patient, and six patients were asymptomatic and were discovered incidentally. Peripheral eosinophilia was present in 14 patients (14/21, 66.7%), and abnormal liver function tests were found in 16 patients (16/21, 76.2%). Of the 19 patients who underwent CT imaging, 17 patients showed multiple mixed hypodense lesions or multiple cysts with inlaying septation with separate irregular rims or circular enhancement on post-contrast CT images. Tunnel-shaped micro abscesses and necrotic cavities were found in the lesions of 12 of those 17 patients. The other two patients showed smaller cystic masses. MRI showed faveolate T1 hypointense and T2 hyperintense areas in the liver parenchyma with rim or peripheral enhancement. Nodular or circular hyperintense materials were found scattered in the lesions on T1-weighted imaging. Conclusion: CT and MRI can reveal the radiological-pathological features of HP. Together with laboratory findings, MRI and CT findings may provide diagnostic clues, especially in endemic

  12. Imaging Characteristics of Dural Arteriovenous Fistulas Involving the Vein of Galen: A Comprehensive Review.

    Science.gov (United States)

    Kassem, Mohammad W; Choi, Paul J; Iwanaga, Joe; Mortazavi, Martin M; Tubbs, R Shane

    2018-02-11

    Vein of Galen aneurysmal malformation (VGAM) is a rare angiopathy, which most commonly presents in infancy. Although very rare, it is associated with high morbidity and mortality rates. In order to minimize such morbid rates, a prompt diagnosis followed by a timely initiation of management is crucial. Multiple antenatal and postnatal imaging techniques for the diagnosis have been described and discussed in the literature. However, to our knowledge, a comprehensive review exploring such a list of imaging options for VGAM has never been established. We aim to review the diagnostic tools to aid in better understanding of the investigative modalities physicians may choose from when treating patients with a VGAM.

  13. Imaging characteristics of lipofibromatosis presenting as a shoulder mass in a 16-month-old girl

    International Nuclear Information System (INIS)

    Walton, James R.; Donaldson, Matthew M.; Mazuru, Dana G.; Green, Brian A.

    2010-01-01

    Lipofibromatosis is a rare, benign fibrofatty tumor of childhood. Since the tumor was first characterized in 2000, only a few additional cases have been reported. The classic presentation of lipofibromatosis is a slow-growing mass arising in a distal extremity, with boys more commonly affected than girls. We report a 16-month-old girl who presented with a lipofibromatosis in her left scapular region that increased 30% in size during a 6-week period. Although previous case reports of lipofibromatosis have emphasized immunohistological findings, this paper focuses on imaging findings and discusses the utility of imaging in the differential diagnosis of pediatric soft-tissue tumors. (orig.)

  14. Imaging characteristics of lipofibromatosis presenting as a shoulder mass in a 16-month-old girl

    Energy Technology Data Exchange (ETDEWEB)

    Walton, James R.; Donaldson, Matthew M.; Mazuru, Dana G. [University of Missouri School of Medicine, Department of Radiology, Columbia, MO (United States); Green, Brian A. [University of Missouri School of Medicine, Department of Radiology, Columbia, MO (United States); Memphis Radiological, PC, Memphis, TN (United States)

    2010-12-15

    Lipofibromatosis is a rare, benign fibrofatty tumor of childhood. Since the tumor was first characterized in 2000, only a few additional cases have been reported. The classic presentation of lipofibromatosis is a slow-growing mass arising in a distal extremity, with boys more commonly affected than girls. We report a 16-month-old girl who presented with a lipofibromatosis in her left scapular region that increased 30% in size during a 6-week period. Although previous case reports of lipofibromatosis have emphasized immunohistological findings, this paper focuses on imaging findings and discusses the utility of imaging in the differential diagnosis of pediatric soft-tissue tumors. (orig.)

  15. Prevalence and signal characteristics of late gadolinium enhancement on contrast-enhanced magnetic resonance imaging in patients with takotsubo cardiomyopathy

    International Nuclear Information System (INIS)

    Nakamori, Shiro; Matsuoka, Koji; Onishi, Katsuya

    2012-01-01

    The background of this study was to determine the prevalence and signal intensity (SI) characteristics of late gadolinium enhancement (LGE) on magnetic resonance imaging (MRI) in takotsubo cardiomyopathy (TC). Cine, black-blood T2-weighted and LGE MR images were acquired in 23 patients with TC within 72h of onset. Wall motion abnormality (WMA), edema and LGE were evaluated with a 16-segment model. The SI characteristics of LGE were analyzed using SI distribution in remote normal segments as reference. Follow-up MRI was performed 3 months later. Retrospective analysis of LGE MRI was also performed in 10 patients with acute myocardial infarction (AMI) to compare the SI characteristics between TC and AMI. In acute phase, WMA and edema were observed in 236 (64%) and 205 (56%) of 368 segments. LGE was observed in 10 (2.7%) of 368 segments and in 5 (22%) of 23 patients. All LGE lesions in TC exhibited transmural enhancement. The contrast-to-noise ratio (CNR) in TC was significantly lower than that of AMI (3.1±0.3 standard deviations (SD) vs. 6.1±1.2 SD, P<0.01), and CNR value of 4 was useful for distinguishing TC from AMI. Both LGE and WMA disappeared within 12 months. Grey myocardial signal on LGE MRI may be observed in patients with TC. However, the extent of LGE is substantially less than that of WMA and edema, and disappears within 12 months. (author)

  16. Investigation of the spray characteristics for a secondary fuel injection nozzle using a digital image processing method

    Science.gov (United States)

    Jeong, Haeyoung; Lee, Kihyung; Ikeda, Yuji

    2007-05-01

    There are many ways to reduce diesel engine exhaust emissions. However, NOx emission is difficult to reduce because the hydrocarbon (HC) concentration in a diesel engine is not sufficient for NOx conversion. Therefore, in order to create stoichiometric conditions in the De-NOx catalyst, a secondary injection system is designed to inject liquid HC into the exhaust pipe. The atomization and distribution characteristics of the HC injected from a secondary injector are key technologies to obtain a high NOx conversion because inhomogeneous droplets of injected HC cause not only high fuel consumption but also deterioration of NOx emission. This paper describes the spray characteristics of a secondary injector including the spray angle, penetration length and breakup behaviour of the spray to optimize the reduction rate of the NOx catalyst. In this study, various optical diagnostics were applied to investigate these spray characteristics, the atomization mechanism and spray developing process. The visualization and image processing method for the spray pulsation were developed by high speed photography. The influence of the fuel supply pressure on the spray behaviour and a more detailed spray developing process have been analysed experimentally using image processing. Finally, the experimental results were used to correlate the spray structure to the injection system performance and to provide a design guide for a secondary injector nozzle.

  17. The chameleon of neuroinflammation : magnetic resonance imaging characteristics of natalizumab-associated progressive multifocal leukoencephalopathy

    NARCIS (Netherlands)

    Wattjes, Mike P.; Richert, Nancy D.; Killestein, Joep; de Vos, Marlieke; Sanchez, Esther; Snaebjornsson, Petur; Cadavid, Diego; Barkhof, Frederik

    2013-01-01

    Natalizumab is a monoclonal antibody against 4-integrin approved for the treatment of multiple sclerosis (MS) due to a positive effect on clinical and magnetic resonance imaging (MRI) outcome measures. However, one relatively rare but serious side effect of this drug is a higher risk of developing

  18. Intrusive Images in Psychological Disorders: Characteristics, Neural Mechanisms, and Treatment Implications

    Science.gov (United States)

    Brewin, Chris R.; Gregory, James D.; Lipton, Michelle; Burgess, Neil

    2010-01-01

    Involuntary images and visual memories are prominent in many types of psychopathology. Patients with posttraumatic stress disorder, other anxiety disorders, depression, eating disorders, and psychosis frequently report repeated visual intrusions corresponding to a small number of real or imaginary events, usually extremely vivid, detailed, and…

  19. An MRI Study of Superior Temporal Gyrus Volume in Women With Schizotypal Personality Disorder

    OpenAIRE

    Dickey, Chandlee C.; McCarley, Robert William; Voglmaier, Martina M.; Niznikiewicz, Margaret A.; Seidman, Larry Joel; Demeo, Susan; Frumin, Melissa; Shenton, Martha Elizabeth

    2003-01-01

    Objective: An abnormal superior temporal gyrus has figured prominently in schizophrenia research, and left superior temporal gyrus volume has been shown to be smaller in male subjects with schizotypal personality disorder. This is the first structural magnetic resonance imaging study to examine a group of female subjects with schizotypal personality disorder. Method: The superior temporal gyrus was drawn on coronal images acquired from female subjects recruited from the community (schizotypal...

  20. Hemangiomas revisited: the useful, the unusual and the new. Pt. 1. Overview and clinical and imaging characteristics

    International Nuclear Information System (INIS)

    Restrepo, Ricardo; Cervantes, Luisa F.; Altman, Nolan R.; Palani, Rajaneeshankar; Duarte, Ana-Margarita; Amjad, Ibrahim

    2011-01-01

    Hemangiomas are common vascular tumors occurring in children. Though most of the lesions present in infants and young children with a typical appearance, it is important to understand that they all do not behave in the same way. Rather, they are a group of vascular lesions with different clinico-pathological subtypes, with their clinical behavior varying with the stage of the tumor as well. As such, they can and do have a varied clinical, imaging and pathological appearance according to the location of the tumor and also the stage at which the patient is seen. In this pictorial essay, the classification, pathogenesis, clinical appearance, natural history and imaging characteristics of hemangiomas are reviewed and illustrated. (orig.)

  1. Enhanced Depth SD-OCT Images Reveal Characteristic Choroidal Changes in Patients With Vogt-Koyanagi-Harada Disease.

    Science.gov (United States)

    Li, Mei; Liu, Qiuhui; Luo, Yan; Li, Yonghao; Lin, Shaofen; Lian, Ping; Yang, Qiufen; Li, Xiaofang; Liu, Xialin; Sadda, SriniVas; Lu, Lin

    2016-11-01

    To identify characteristic choroidal changes of patients with Vogt-Koyanagi-Harada (VKH) disease at different stages. Fifty-four patients with VKH in the acute uveitic or convalescent stages, 24 patients with central serous chorioretinopathy (CSC), and 54 normal participants were enrolled in this prospective, observational study. Enhanced depth imaging spectral-domain optical coherence tomography scans were captured for all subjects to allow for comparison of choroidal morphological findings. Numerous round or oval hyperreflective profiles with hyporeflective cores, corresponding to choroidal vessels, were observed in the choroid of control participants and patients with CSC; whereas the numbers of these profiles were markedly decreased in the choroid of VKH patients in both the acute uveitic and convalescent stages. A reduction in vascular profiles in the choroid is observed in VKH and may aid in the differentiation with disorders such as CSC. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:1004-1012.]. Copyright 2016, SLACK Incorporated.

  2. Immunoglobulin G4 -related kidney disease: A comprehensive pictorial review of the imaging spectrum, Mimickers, and clinicopathological characteristics

    International Nuclear Information System (INIS)

    Seo, Ni Eun; Kim, Jin Hee; Byun, Jae Ho; Lee, Seung Soo; Kim, Hyoung Jung; Lee, Moon Gyu

    2015-01-01

    Immunoglobulin G4 (IgG4)-related kidney disease (IgG4-KD) has recently been demonstrated to be an important part of IgG4-related sclerosing disease (IgG4-SD). However, since IgG4-KD is still relatively unfamiliar to radiologists and physicians as compared to IgG4-SD involving other organs, it could, therefore, be easily missed. In this article, we present a comprehensive pictorial review of IgG4-KD with regards to the imaging spectrum, mimickers, and clinicopathologic characteristics, based on our clinical experience with 48 patients during the past 13 years, as well as a literature review. Awareness of the broad imaging spectrum of IgG4-KD and differential diagnosis from its mimickers will thus facilitate its early diagnosis and treatment

  3. Cine-MR imaging in determining the flow characteristics of CSF and blood in spinal and intracranial lesions

    International Nuclear Information System (INIS)

    Post, M.J.D.; Quencer, R.M.; Green, B.A.; Hinks, R.S.; Sklar, E.M.L.; Patchen, S.J.

    1988-01-01

    The purpose of this prospective study was to determine the value of cine magnetic resonance (MR) imaging in assessing the flow patterns of patients with vascular cord neoplasms, spinal cord and subarachnoid cysts, obstructive hydrocephalus, and intracranial aneurysms. The authors' results in 26 patients showed that cine MR imaging can be used to (1) identify spinal neoplasms with prominent vascular supply; (2) help distinguish spinal cord cysts occurring above a spinal cord tumor from tumoral cysts; (3) determine which spinal cord or subarachnois cysts need shunting and, postoperatively, which cysts are adequately decompressed; (4) establish which tonsillar herniations in Chiari malformations may require resection; (5) determine the site of the block in obstructive hydrocephalus; and (6) determine the flow characteristics of an aneurysm

  4. Study on the dose response characteristics of a scanning liquid ion-chamber electronic portal imaging device

    CERN Document Server

    Ma Shao Gang; Song Yi Xin

    2002-01-01

    Objective: To study the dose response characteristics and the influence factors such as gantry angle, field size and acquisition mode on the dosimetric response curves, when using a scanning liquid ion-chamber electronic portal imaging device (EPID) for dose verification. Methods: All experiments were carried out on a Varian 600 C/D accelerator (6 MV X-ray) equipped with a Varian PortalVision sup T sup M MK2 type EPID. To obtain the dose response curve, the relationship between the incident radiation intensity to the detector and the pixel value output from the EPID were established. Firstly, the different dose rates of 6 MV X-rays were obtained by varying SSD. Secondly, three digital portal images were acquired for each dose rate using the EPID and averaged to avoid the influence of the dose rate fluctuations of the accelerator. The pixel values of all images were read using self-designed image analysis software, and and average for a region consisting of 11 x 11 pixels around the center was taken as the res...

  5. Imaging characteristics of subcutaneous amyloid deposits in diabetic patients: the ''insulin ball''

    International Nuclear Information System (INIS)

    Tanio, Noriko; Nozaki, Taiki; Matsusako, Masaki; Starkey, Jay; Suzuki, Koyu

    2018-01-01

    The purpose of this study was to describe the imaging characteristics of subcutaneous amyloid deposits occurring at sites of insulin injection, commonly known as ''insulin balls,'' in diabetic patients on ultrasound, CT, and MRI with pathologic correlation. We retrospectively reviewed the radiographic findings of 14 lesions in 9 patients diagnosed with subcutaneous amyloid deposits at our institution between 2005-2015. Three board-certified radiologists analyzed the following: (1) the shape, size, margin, morphologic characteristics, and blood flow on US using the color Doppler signal, (2) shape, size, margin, attenuation, and presence or absence of contrast enhancement on CT, and (3) shape, size, margin, signal intensity, and presence or absence of contrast enhancement on MRI. All lesions showed ill-defined hypovascular subcutaneous nodules with irregular margins. The median diameter of lesions was 50.4 mm on US, 46.8 mm on CT, and 51.4 mm on MRI. The internal echogenicity of subcutaneous amyloid deposits was hypoechoic and heterogeneous on US. All lesions showed isodensity compared to muscle with irregular margins and minimal contrast enhancement on CT. Both T1- and T2-weighted MR images showed low signal intensity compared with subcutaneous fat. Normal diffusion and minimal contrast enhancement were seen. Subcutaneous amyloid deposits which cause insulin resistance are typically ill-defined and heterogeneous hypovascular subcutaneous nodules with irregular margins on imaging that correspond to insulin injection sites. It is also characteristic that T2WI shows low intensity compared with fat on MRI, reflective of the amyloid content. (orig.)

  6. Imaging characteristics of subcutaneous amyloid deposits in diabetic patients: the ''insulin ball''

    Energy Technology Data Exchange (ETDEWEB)

    Tanio, Noriko; Nozaki, Taiki; Matsusako, Masaki; Starkey, Jay [St. Luke' s International Hospital, Department of Radiology, Tokyo (Japan); Suzuki, Koyu [St. Luke' s International Hospital, Department of Pathology, Tokyo (Japan)

    2018-01-15

    The purpose of this study was to describe the imaging characteristics of subcutaneous amyloid deposits occurring at sites of insulin injection, commonly known as ''insulin balls,'' in diabetic patients on ultrasound, CT, and MRI with pathologic correlation. We retrospectively reviewed the radiographic findings of 14 lesions in 9 patients diagnosed with subcutaneous amyloid deposits at our institution between 2005-2015. Three board-certified radiologists analyzed the following: (1) the shape, size, margin, morphologic characteristics, and blood flow on US using the color Doppler signal, (2) shape, size, margin, attenuation, and presence or absence of contrast enhancement on CT, and (3) shape, size, margin, signal intensity, and presence or absence of contrast enhancement on MRI. All lesions showed ill-defined hypovascular subcutaneous nodules with irregular margins. The median diameter of lesions was 50.4 mm on US, 46.8 mm on CT, and 51.4 mm on MRI. The internal echogenicity of subcutaneous amyloid deposits was hypoechoic and heterogeneous on US. All lesions showed isodensity compared to muscle with irregular margins and minimal contrast enhancement on CT. Both T1- and T2-weighted MR images showed low signal intensity compared with subcutaneous fat. Normal diffusion and minimal contrast enhancement were seen. Subcutaneous amyloid deposits which cause insulin resistance are typically ill-defined and heterogeneous hypovascular subcutaneous nodules with irregular margins on imaging that correspond to insulin injection sites. It is also characteristic that T2WI shows low intensity compared with fat on MRI, reflective of the amyloid content. (orig.)

  7. The diagnostic reliability of the quantitative pivot-shift evaluation using an electromagnetic measurement system for anterior cruciate ligament deficiency was superior to those of the accelerometer and iPad image analysis.

    Science.gov (United States)

    Tanaka, Toshikazu; Hoshino, Yuichi; Miyaji, Nobuaki; Ibaragi, Kazuyuki; Nishida, Kyohei; Nishizawa, Yuichiro; Araki, Daisuke; Kanzaki, Noriyuki; Matsushita, Takehiko; Kuroda, Ryosuke

    2017-10-14

    Several non-invasive devices have been developed to obtain quantitative assessment of the pivot-shift test in clinical setting using similar but diverse measurement parameters. However, the clinical usability of those measurements has yet to be closely investigated and compared. The purpose of this study was to compare the diagnostic accuracy of three non-invasive measurement devices for the pivot-shift test. Thirty patients with unilateral anterior cruciate ligament (ACL) injury were enrolled. The pivot-shift test was performed under general anaesthesia. Three devices, an accelerometer system (KiRA), an image analysis iPad application (iPad), and electromagnetic measurement system (EMS), were used simultaneously to provide two parameters, namely tibial acceleration monitored using KiRA and EMS, and tibial translation recorded using iPad and EMS. Side-to-side differences in each parameter and correlation between the measurements were tested, and a receiver-operating characteristic (ROC) curve analysis was conducted to compare their measurement accuracy. Significant side-to-side differences were successfully detected using any of the measurements (all p iPad and the EMS for the translation (r = 0.28; p iPad for tibial acceleration and translation, respectively. Although all three measurements were similarly capable of detecting ACL deficiency, the EMS has the advantage of comprehensive evaluation of the pivot-shift test by evaluating both tibial acceleration and translation with higher accuracy than those of KiRA and iPad. It could be suggested that any of those measurement tools might improve the clinical diagnosis of ACL insufficiency. Diagnostic study of consecutive patients with a universally applied gold standard, Level Ib.

  8. Characteristics of Xanthosoma sagittifolium roots during cooking, using physicochemical analysis, uniaxial compression, multispectral imaging and low field NMR spectroscopy

    DEFF Research Database (Denmark)

    Boakye, Abena Achiaa; Gudjónsdóttir, María; Skytte, Jacob Lercke

    2017-01-01

    and white varieties of cocoyam roots were thus analysed by low field nuclear magnetic resonance relaxometry, multispectral imaging, uniaxial compression testing, and relevant physicochemical analysis in the current study. Both varieties had similar dry matter content, as well as physical and mechanical...... of that spectral region for rapid analysis of dry matter and water content of the roots. The small, but significant differences in the structural and gelatinization characteristics of the two varieties indicated that they may not be equally suited for further processing, e.g. to flours or starches. Processors thus...

  9. Structure and Filling Characteristics of Paleokarst Reservoirs in the Northern Tarim Basin, Revealed by Outcrop, Core and Borehole Images

    Directory of Open Access Journals (Sweden)

    Tian Fei

    2017-06-01

    Full Text Available The Ordovician paleokarst reservoirs in the Tahe oilfield, with burial depths of over 5300 m, experienced multiple phases of geologic processes and exhibit strong heterogeneity. Core testing can be used to analyse the characteristics of typical points at the centimetre scale, and seismic datasets can reveal the macroscopic outlines of reservoirs at the >10-m scale. However, neither method can identify caves, cave fills and fractures at the meter scale. Guided by outcrop investigations and calibrations based on core sample observations, this paper describes the interpretation of high longitudinal resolution borehole images, the identification of the characteristics of caves, cave fills (sedimentary, breccia and chemical fills and fractures in single wells, and the identification of structures and fill characteristics at the meter scale in the strongly heterogeneous paleokarst reservoirs. The paleogeomorphology, a major controlling factor in the distribution of paleokarst reservoirs, was also analysed. The results show that one well can penetrate multiple cave layers of various sizes and that the caves are filled with multiple types of fill. The paleogeomorphology can be divided into highlands, slopes and depressions, which controlled the structure and fill characteristics of the paleokarst reservoirs. The results of this study can provide fundamental meter-scale datasets for interpreting detailed geologic features of deeply buried paleocaves, can be used to connect core- and seismic-scale interpretations, and can provide support for the recognition and development of these strongly heterogeneous reservoirs.

  10. Morel-Lavallée Injuries: A Multimodality Approach to Imaging Characteristics.

    Science.gov (United States)

    Spain, James A; Rheinboldt, Matthew; Parrish, David; Rinker, Eric

    2017-02-01

    Morel-Lavallée lesions are relatively rare closed degloving injuries caused by a shearing force resulting in separation of the dermis and the hypodermis from the subjacent deeper fascia. Although most commonly encountered lateral to the greater trochanter, these injuries may occur throughout the body in a variety of locations. Separation of the hypodermal tissue planes results in a complex serosanguinous fluid collection with areas of internal fat necrosis. The imaging appearance is variable and nonspecific, potentially mimicking superficial hemorrhagic bursitis, or cystic or necrotic primary soft tissue neoplasms. If not treated in the acute or early subacute setting, these collections are at risk of superinfection, overlying tissue necrosis, and continued expansion. In this article, we will review the pathophysiology, cross-sectional imaging features, and differential diagnostic considerations of Morel-Lavallée lesions as well as discuss management and treatment options. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  11. Characteristics of the retinal images of the eye optical systems with implanted intraocular lenses

    Science.gov (United States)

    Siedlecki, Damian; Zając, Marek; Nowak, Jerzy

    2007-04-01

    Cataract, or opacity of crystalline lens in the human eye is one of the most frequent reasons of blindness nowadays. Removing the pathologically altered crystalline lens and replacing it with artificial implantable intraocular lens (IOL) is practically the only therapy in this illness. There exist a wide variety of artificial IOL types on the medical market, differing in their material and design (shape). In this paper six exemplary models of IOL's made of PMMA, acrylic and silicone are considered. The retinal image quality is analyzed numerically on the basis of Liou-Brennan eye model with these IOL's inserted. Chromatic aberration as well as polychromatic Point Spread Function and Modulation Transfer Function are calculated as most adequate image quality measures. The calculations made with Zemax TM software show the importance of chromatic aberration correction.

  12. Specific Image Characteristics Influence Attitudes about Chimpanzee Conservation and Use as Pets

    OpenAIRE

    Ross, Stephen R.; Vreeman, Vivian M.; Lonsdorf, Elizabeth V.

    2011-01-01

    Chimpanzees are endangered in their native Africa but in the United States, they are housed not only in zoos and research centers but owned privately as pets and performers. In 2008, survey data revealed that the public is less likely to think that chimpanzees are endangered compared to other great apes, and that this is likely the result of media misportrayals in movies, television and advertisements. Here, we use an experimental survey paradigm with composite images of chimpanzees to determ...

  13. A case of a resectable single hepatic epithelioid hemangioendothelioma with characteristic imaging by ADC map.

    Science.gov (United States)

    Okano, Hiroshi; Nakajima, Hideki; Tochio, Tomomasa; Suga, Daisuke; Kumazawa, Hiroaki; Isono, Yoshiaki; Tanaka, Hiroki; Matsusaki, Shimpei; Sase, Tomohiro; Saito, Tomonori; Mukai, Katsumi; Nishimura, Akira; Matsushima, Nobuyoshi; Baba, Youichirou; Murata, Tetsuya; Hamada, Takashi; Taoka, Hiroki

    2015-12-01

    A 47-year-old woman with a single-nodule hepatic tumor was referred to our hospital. She had no symptoms. The tumor was located at the surface of the right lobe of the liver; it showed peripheral low signal intensity on a magnetic resonance imaging apparent diffusion coefficient (ADC) map, and an influx of blood flow into the peripheral area of the tumor at the early vascular phase on perflubutane microbubble (Sonazoid(®)) contrast-enhanced (CE) ultrasonography. Since we suspected a malignant tumor, the patient underwent surgical resection. The hepatic tumor was resected curatively. Pathological examination revealed that the tumor was composed of epithelioid cells with an epithelioid structure and/or cord-like structure. Immunohistochemical staining was positive for cluster of differentiation 34 and factor VIII-related antigen. Based on the above, a final diagnosis of hepatic epithelioid hemangioendothelioma (EHE) was made. Hepatic EHE is a rare hepatic tumor: only a few cases of hepatic EHE with curative resection have been reported. We were unable to reach a diagnosis of hepatic EHE by imaging studies; however, an ADC map was useful in showing the malignant potential of the tumor, and CE ultrasonography was useful in revealing the peripheral blood flow of the tumor. When an unusual hepatic mass is encountered, hepatic EHE should be kept in mind, and the mass should be inspected with more than one imaging modality, including an ADC map, in the process of differential diagnosis.

  14. Whole-body imaging of whole-organ, subresolution, basic functional unit (BFU) perfusion characteristics

    Science.gov (United States)

    Dong, Yue; Ritman, Erik L.

    2008-08-01

    A BFU is an organ's smallest assembly of diverse cells that functions like the organ, such as the liver's hepatic lobules. There are approximately 107 BFUs in a human organ. These 100-200 μm structures are perfused by capillaries fed by a terminal arteriole (15μm diameter). BFU sizes, function and number per organ vary with disease, either by loss of BFUs and/or their decrease in function. The BFU is the upper limit of a spherical assembly of cells, immersed in a suitably nutrient medium, which can survive without its own blood supply. However, each BFU has its own blood supply to support the extra energy and/or solutes needed for providing its physiological function (e.g., contraction or secretion). A BFU function is best evaluated by its micro-perfusion, which can be readily evaluated with whole-body CT. Resolution of individual BFUs within in-situ organs, using clinical imaging devices, would require high radiation doses and/or the intolerably long scan-durations needed for suitable signal-to-noise image-data. However, it is possible to obtain a statistical description of the BFU number, size and function from wholebody CT by way of a model. In this study we demonstrate this capability by using the distribution of myocardial terminal arteriolar perfusion territories by way of a nested, multiple, regions-of-interest analysis of the heart wall imaged during transient opacification of its blood supply.

  15. The Effect of Image Potential on the Current-Voltage Characteristics of a Ferritin-layer

    Directory of Open Access Journals (Sweden)

    Eunjung Bang

    2010-11-01

    Full Text Available Considering for the concept of power storage systems, such as those used to supply power to microelectronic devices, ferritins have aroused a lot of interests for applications in bioelectrochemical devices. And electron transfer rates from the proteins to electrode surface are key determinants of overall performance and efficiency of the ferritin-based devices. Here we have investigated the electron transport mechanism of ferritin layer which was immobilized on an Au electrode. The current-voltage (I-V curves are obtained by a conductive atomic force microscope (c-AFM as a function of contact area between AFM tip and the ferritin layer. In the low voltage region, I-V curves are affected by both Fowler-Nordheim tunneling and image force. On the other hand, the experimental results are consistent with a Simmons model in a high voltage region, indicating that, as the voltage increases, the image potential has a dominant effect on the electron transport mechanism. These results are attributed to the film-like character of the ferritin layer, which generates an image potential to lower the barrier height in proportion to the voltage increment.

  16. Imaging characteristics, tissue distribution, and spread of a novel oncolytic vaccinia virus carrying the human sodium iodide symporter.

    Directory of Open Access Journals (Sweden)

    Dana Haddad

    Full Text Available INTRODUCTION: Oncolytic viruses show promise for treating cancer. However, to assess therapy and potential toxicity, a noninvasive imaging modality is needed. This study aims to determine the in vivo biodistribution, and imaging and timing characteristics of a vaccinia virus, GLV-1h153, encoding the human sodium iodide symporter (hNIS. METHODS: GLV-1h153 was modified from GLV-1h68 to encode the hNIS gene. Timing of cellular uptake of radioiodide (131I in human pancreatic carcinoma cells PANC-1 was assessed using radiouptake assays. Viral biodistribution was determined in nude mice bearing PANC-1 xenografts, and infection in tumors confirmed histologically and optically via Green Fluorescent Protein (GFP and bioluminescence. Timing characteristics of enhanced radiouptake in xenografts were assessed via (124I-positron emission tomography (PET. Detection of systemic administration of virus was investigated with both (124I-PET and 99m-technecium gamma-scintigraphy. RESULTS: GLV-1h153 successfully facilitated time-dependent intracellular uptake of (131I in PANC-1 cells with a maximum uptake at 24 hours postinfection (P<0.05. In vivo, biodistribution profiles revealed persistence of virus in tumors 5 weeks postinjection at 10(9 plaque-forming unit (PFU/gm tissue, with the virus mainly cleared from all other major organs. Tumor infection by GLV-1h153 was confirmed via optical imaging and histology. GLV-1h153 facilitated imaging virus replication in tumors via PET even at 8 hours post radiotracer injection, with a mean %ID/gm of 3.82 ± 0.46 (P<0.05 2 days after intratumoral administration of virus, confirmed via tissue radiouptake assays. One week post systemic administration, GLV-1h153-infected tumors were detected via (124I-PET and 99m-technecium-scintigraphy. CONCLUSION: GLV-1h153 is a promising oncolytic agent against pancreatic cancer with a promising biosafety profile. GLV-1h153 facilitated time-dependent hNIS-specific radiouptake in pancreatic

  17. Writing superiority in cued recall

    Directory of Open Access Journals (Sweden)

    Carina eFueller

    2013-10-01

    Full Text Available In list learning paradigms with free recall, written recall has been found to be less susceptible to intrusions of related concepts than spoken recall when the list items had been visually presented. This effect has been ascribed to the use of stored orthographic representations from the study phase during written recall (Kellogg, 2001. In other memory retrieval paradigms, either better recall for modality-congruent items or an input-independent writing superiority effect have been found (Grabowski, 2005. In a series of four experiments using a paired associate (PA learning paradigm we tested (a whether output modality effects on verbal recall can be replicated in a paradigm that does not involve the rejection of semantically related intrusion words, (b whether a possible superiority for written recall was due to a slower response onset for writing as compared to speaking in immediate recall, and (c whether the performance in PA word recall was correlated with performance in an additional episodic memory task. We found better written recall in the first half of the recall phase, irrespective of the modality in which the material was presented upon encoding. An explanation based on longer response latencies for writing and hence more time for retrieval could be ruled out by showing that the effect persisted in delayed response versions of the task. Although there was some evidence that stored additional episodic information may contribute to the successful retrieval of associate words, this evidence was only found in the immediate response experiments and hence is most likely independent from the observed output modality effect. In sum, our results from a PA learning paradigm suggest that superior performance for written versus spoken recall cannot be (solely explained in terms of additional access to stored orthographic representations from the encoding phase. Our findings rather suggest a general writing-superiority effect at the time of memory

  18. Growth characteristics and imaging properties of the morris hepatoma 3924a in ACI rats: A suitable model for transarterial chemoembolization

    International Nuclear Information System (INIS)

    Truebenbach, Jochen; Graepler, Florian; Pereira, Philippe L; Ruck, Peter; Lauer, Ulrich; Gregor, Michael; Claussen, Claus-D.; Huppert, Peter E.

    2000-01-01

    Purpose: For experimental studies investigating modalities and efficacy of transarterial chemoembolization (TACE) in hepatocellular carcinoma (HCC) an animal model resembling the human situation as closely as possible would be appropriate. Specifically, reproducible tumor growth characteristics with the capability for appropriate in vivo imaging to monitor treatment efficacy are required.Methods: Morris hepatoma 3924A was implanted into the liver of 30 ACI rats. Tumor growth was followed by angiography (n=10), ultrasound (US, n=30), native computed tomography (CT. n=16), and native magnetic resonance imaging (MRU n=30) between day 8 and day 36 after implantation. The radiological morphological characteristics were compared with the macroscopic and microscopic histological findings of the explanted tumors.Results: In all 30 animals a solitary liver tumor was found and macroscopically no signs of metastases, ascites, or peritoneal tumor were visible. On histopathological examination tumor sizes ranged between 27 ± 3 mm 3 (day 8) and 3468 ± 79 mm 3 (day 36). The first signs of tumor necrosis occurred at day 16. US allowed tumor visualization from day 8, MRI from day 8, angiography from day 10, and CT from day 14.Conclusions: The tumor model has the potential to be used for the visualization of tumor growth by MRI and US. The potential for monitoring therapeutic effects of TACE needs to be investigated.

  19. Using Naïve Bayesian Analysis to Determine Imaging Characteristics of KRAS Mutations in Metastatic Colon Cancer.

    Science.gov (United States)

    Pershad, Yash; Govindan, Siddharth; Hara, Amy K; Borad, Mitesh J; Bekaii-Saab, Tanios; Wallace, Alex; Albadawi, Hassan; Oklu, Rahmi

    2017-09-02

    Genotype, particularly Ras status, greatly affects prognosis and treatment of liver metastasis in colon cancer patients. This pilot aimed to apply word frequency analysis and a naive Bayes classifier on radiology reports to extract distinguishing imaging descriptors of wild-type colon cancer patients and those with v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations. In this institutional-review-board-approved study, we compiled a SNaPshot mutation analysis dataset from 457 colon adenocarcinoma patients. From this cohort of patients, we analyzed radiology reports of 299 patients (> 32,000 reports) who either were wild-type (147 patients) or had a KRAS (152 patients) mutation. Our algorithm determined word frequency within the wild-type and mutant radiology reports and used a naive Bayes classifier to determine the probability of a given word belonging to either group. The classifier determined that words with a greater than 50% chance of being in the KRAS mutation group and which had the highest absolute probability difference compared to the wild-type group included: "several", "innumerable", "confluent", and "numerous" ( p colon adenocarcinoma. Moreover, likely characteristic imaging traits of mutant tumors make probabilistic word analysis useful in identifying unique characteristics and disease course, with applications ranging from radiology and pathology reports to clinical notes.

  20. Mean Characteristics of Conical Vortices Above Roof Eaves of Low–Rise Cubic Buildings Using Particle Image Velocimetry

    Directory of Open Access Journals (Sweden)

    M. Gamboa–Marrufo

    2009-04-01

    Full Text Available Fluctuating low pressures near the edges of flat roofs are often caused when the wind impinges on one corner of the building so that conical vortices form above the diagonal roof edges. In turbulent flow, these vortices vary in position and strength and the underlying surface pressures fluctuate accordingly. A preliminary approach to the study of the mechanism linking instantaneous roof edge pressures with the wind vortical structures involves the evaluation of mean characteristics and positions of the latter. However the flow examination has so far been severely limited by the restriction of available anemometers to single–point sampling. In this experimental study, a 200mm cube has been used to model a building with a flat square roof set at an angle of 45° to the oncoming flow direction, and a Particle Image Velocimetry system was used to capture instantaneous two–dimensional velocity vector images of entire flow cross–sections, both normal to the vortex axis and in planes parallel to that axis. The se vector maps were used to estimate the mean characteristics of the vortices and appropriate observation–plane directions to measure wind velocities in the study of the instantaneous problem.

  1. Clinical and imaging characteristics of 16 patients with autoimmune neuronal synaptic encephalitis.

    Science.gov (United States)

    Kamble, N; Netravathi, M; Saini, J; Mahadevan, A; Yadav, R; Nalini, A; Pal, P K; Satishchandra, P

    2015-01-01

    Autoimmune neuronal synaptic encephalitis (AIE) encompasses a heterogeneous group of disorders characterized by immune-mediated neuronal cell destruction. In this study, we aim to study the clinical features, imaging profile and treatment outcome of patients with AIE. This is a chart review of 16 (M: F-3:13) patients with AIE from 2011 to 2015. Among the patients, 10 had anti-NMDA, 4 had anti-TPO, and 2 had anti-VGKC antibody positivity. Cognitive impairment and seizures were the predominant symptoms present in nearly all patients, followed by psychiatric disturbances (87.5%), mutism (62.5%), movement disorders (62.5%), myoclonic jerks (37.5%) and visual hallucinations (18.75%). Magnetic resonance imaging (MRI) of the brain was available in 15 patients; it was abnormal in 53.3% patients. Abnormalities were seen in all patients with anti-VGKC positivity; and, 60% of patients with anti-NMDA positivity. Imaging was normal in 26.7% of the patients (3: anti-NMDA; and, 1: anti-TPO positivity); and, diffuse cerebral atrophy was noted in rest of the 20% (3: anti-TPO positivity) patients. All patients improved gradually with immunomodulation. All patients with anti-VGKC, anti-NMDA and anti-TPO antibody positivity presented with a triad of behavioral changes, impaired cognition and seizures. Mutism was a predominant symptom in patients with an anti-NMDA antibody positivity, which may help in the early identification of this disorder. MRI brain showed changes restricted to limbic structures in anti-NMDA and anti-VGKC antibody positivity. An early diagnosis and treatment of autoimmune encephalitis is essential for a better outcome and for prevention of long-term sequel.

  2. Performance characteristics of a small animal PET camera for molecular imaging

    International Nuclear Information System (INIS)

    Hastings, D.L.; Reader, A.J.; Julyan, P.J.; Zweit, J.; Jeavons, A.P.; Jones, T.

    2007-01-01

    The performance of a novel type of animal PET camera, the quad High-Density Avalanche Chamber (HIDAC) was assessed for a non-rotating 16-module system. Spatial resolution was 1.0 mm, and invariant within a standard deviation ≤5%. Absolute sensitivity was 0.95%, and the scatter-background corrected sensitivity was 0.75%. The count rate capability was linear at typical activities used in animal imaging, with a 20% loss at 11.5 MBq. The camera demonstrates small regions of radiotracer uptake with excellent detail in the mouse

  3. Can Laws Be a Potential PET Image Texture Analysis Approach for Evaluation of Tumor Heterogeneity and Histopathological Characteristics in NSCLC?

    Science.gov (United States)

    Karacavus, Seyhan; Yılmaz, Bülent; Tasdemir, Arzu; Kayaaltı, Ömer; Kaya, Eser; İçer, Semra; Ayyıldız, Oguzhan

    2018-04-01

    We investigated the association between the textural features obtained from 18 F-FDG images, metabolic parameters (SUVmax , SUVmean, MTV, TLG), and tumor histopathological characteristics (stage and Ki-67 proliferation index) in non-small cell lung cancer (NSCLC). The FDG-PET images of 67 patients with NSCLC were evaluated. MATLAB technical computing language was employed in the extraction of 137 features by using first order statistics (FOS), gray-level co-occurrence matrix (GLCM), gray-level run length matrix (GLRLM), and Laws' texture filters. Textural features and metabolic parameters were statistically analyzed in terms of good discrimination power between tumor stages, and selected features/parameters were used in the automatic classification by k-nearest neighbors (k-NN) and support vector machines (SVM). We showed that one textural feature (gray-level nonuniformity, GLN) obtained using GLRLM approach and nine textural features using Laws' approach were successful in discriminating all tumor stages, unlike metabolic parameters. There were significant correlations between Ki-67 index and some of the textural features computed using Laws' method (r = 0.6, p = 0.013). In terms of automatic classification of tumor stage, the accuracy was approximately 84% with k-NN classifier (k = 3) and SVM, using selected five features. Texture analysis of FDG-PET images has a potential to be an objective tool to assess tumor histopathological characteristics. The textural features obtained using Laws' approach could be useful in the discrimination of tumor stage.

  4. Mechanics of bioinspired imaging systems

    Directory of Open Access Journals (Sweden)

    Zhengwei Li

    2016-01-01

    Full Text Available Imaging systems in nature have attracted a lot of research interest due to their superior optical and imaging characteristics. Recent advancements in materials science, mechanics, and stretchable electronics have led to successful development of bioinspired cameras that resemble the structures and functions of biological light-sensing organs. In this review, we discuss some recent progresses in mechanics of bioinspired imaging systems, including tunable hemispherical eyeball camera and artificial compound eye camera. The mechanics models and results reviewed in this article can provide efficient tools for design and optimization of such systems, as well as other related optoelectronic systems that combine rigid elements with soft substrates.

  5. Double elevator weakening for unilateral congenital superior oblique palsy with ipsilateral superior rectus contracture and lax superior oblique tendon.

    Science.gov (United States)

    Khan, Arif O

    2012-06-01

    In unilateral congenital superior oblique palsy, a large hypertropia is sometimes associated with ipsilateral contracture of the superior rectus muscle and apparent overaction of the contralateral superior oblique. Ipsilateral double elevator weakening is one surgical approach; however, this procedure could compromise supraduction. We report a series of three consecutive patients who underwent ipsilateral superior rectus and inferior oblique recessions for unilateral superior oblique palsy. Intraoperatively, all three patients were found to have a lax ipsilateral superior oblique tendon. Postoperatively, all three patients had satisfactory correction of the hypertropia and abnormal head position with minimal supraduction defect. This procedure seems to be an acceptable initial surgical option for treating congenital superior oblique muscle palsy with ipsilateral contracture of the superior rectus muscle, even when the ipsilateral superior oblique tendon is lax. Copyright © 2012 American Association for Pediatric Ophthalmology and Strabismus. Published by Mosby, Inc. All rights reserved.

  6. Imaging and clinical characteristics of children with multiple foci of microsusceptibility changes in the brain on susceptibility-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Niwa, Tetsu [Kanagawa Children' s Medical Center, Department of Radiology, Yokohama (Japan); University Medical Center Utrecht, Department of Radiology, Heidelberglaan 100, PO Box 85500, Utrecht (Netherlands); Aida, Noriko; Fujita, Kazutoshi; Shishikura, Ayako [Kanagawa Children' s Medical Center, Department of Radiology, Yokohama (Japan); Takahara, Taro; Kwee, Thomas C. [University Medical Center Utrecht, Department of Radiology, Heidelberglaan 100, PO Box 85500, Utrecht (Netherlands); Miyata, Daiki [Kanagawa Children' s Medical Center, Department of Circulation Medicine, Yokohama (Japan); Inoue, Tomio [Yokohama City University, Graduate School of Medicine, Department of Radiology, Yokohama (Japan)

    2010-10-15

    Microsusceptibility changes in the brain are well known to correspond with microbleeds or micrometal fragments in adults, but this phenomenon has not been explored well in children. To assess imaging and clinical characteristics of children with multiple foci of microsusceptibility changes using susceptibility-weighted imaging (SWI). Between 2006 and 2008, 12 children with multiple foci of microsusceptibility on SWI without corresponding abnormal signal on conventional MRI were identified and were retrospectively assessed. The locations of foci of microsusceptibility included the cerebral white matter, basal ganglia, brainstem and cerebellar white matter, without any clear systematic anatomic distribution. CT (n = 5) showed no calcification at the locations corresponding to the microsusceptibility on SWI. Conventional MR imaging showed white matter volume loss (n = 5), delayed myelination (n = 2), acute infarction (n = 1), chronic infarction (n = 1), meningitis (n = 1), slight signal abnormality in the white matter (n = 1) and no abnormal findings (n = 1). Follow-up SWI (n = 3) showed no change of the microsusceptibility foci. Interestingly, all children had a history of heart surgery under extracorporeal circulation for congenital heart disease. Multiple foci of microsusceptibility can be seen in the brain on SWI in children with congenital heart disease who underwent heart surgery with extracorporeal circulation. (orig.)

  7. Helical CT finding of carotid-cavernous fistula: a sign of early enhancing superior ophthalmic vein

    International Nuclear Information System (INIS)

    Kim, Jae Hyung; Na, Dong Gyu; Byun, Hong Sik; Ryoo, Jae Wook

    2000-01-01

    The purpose of this study was to determine the diagnostic value of a sign of early enhancing superior ophthalmic vein (SOV), as seen on helical CT images in patients with carotid-cavernous fistula (CCF). This study involved 16 patients with CCF and 28 control patients. Axial CT images with scanning delays of 30 seconds following bolus injection of contrast material (90 mL, 3 mL/sec) were obtained, and this procedure was followed by coronal CT imaging. To determine the presence or absence of early enhancement or, dilatation of the SOV, bulging of the cavernous sinus, and enlargement of extraocular muscle, CT images were analysed by three observers in a blinded, random manner. Early enhancement of SOV was determined to be present where enhancement of the SOV was similar to or stronger than that of the ipsilateral posterior cerebral artery. A sign of early enhancing SOV was seen in 14 of the 16 patients with CCF but in no control patients (88% sensitivity and 100% specificity). The respective sensitivity and specificity of other CT features were 71% and 100% (dilatation of the SOV, as seen on axial images), 60% and 83% (dilatation of the SOV, as seen on coronal images), 71% and 89% (dilatation of the cavernous sinus), and 65% and 98% (enlargement of extraocular muscle). A sign of early enhancing SOV is a characteristic and specific CT finding of CCF, and is useful for the diagnosis of CCF. (author)

  8. Proton density differences in signal characteristics of multiple sclerosis plaques versus white matter lesions of small vessel disease and vasculitis on high-field strength MR images

    International Nuclear Information System (INIS)

    Peyster, R.G.; Siegal, T.L.

    1990-01-01

    This paper determines if variations in signal intensity characteristics on multi-spin-echo images obtained with a high-field-strength magnet can be useful in differentiating demyelinating plaques of multiple sclerosis from other pathologic white matter processes due to small vessel disease and vasculities. Using the first of two multi-spin-echo images obtained with a General Electric 1.5-T magnet, the investigators compared signal intensity characteristics in 30 patients with a firm clinical diagnosis of multiple sclerosis versus a control group of 30 patients with a known clinical history of small-vessel disease and vasculitis are isodense to gray matter on proton-density images

  9. Positron imaging feasibility studies: characteristics of 2-deoxyglucose uptake in rodent and canine neoplasms

    International Nuclear Information System (INIS)

    Larson, S.M.; Weiden, P.L.; Grunbaum, J.

    1981-01-01

    Uptake of [ 3 H]2-deoxyglucose was studied in BALB/c mice with EMT-6 sarcoma, in Buffalo rats with Morris 7777 hepatoma, and in eight dogs with spontaneous neoplasms: five osteosarcomas and three diffuse lymphomas. High tumor-to-tissue ratios were observed for all tumor types studies. In rodents, peak levels of uptake occurred between 30 min and 1 hr, with a slow loss from the tumor of about 10% per hour thereafter. In dogs there was considerable variability in uptake, both between individuals and at different tumor sites within an individual. Necrotic tumor did not take up the radiotracer. Absolute uptakes, when normalized for body weight, were similar for spontaneous and transplanted neoplasms. These studies provide additional support for the concept that positron emission tomography can be used to obtain functional images of important metabolic processes of tumors, including glycolysis

  10. Clinical and imaging characteristics of foraminal nerve root disorders of the lumbar spine

    International Nuclear Information System (INIS)

    Nishi, Tomio; Tani, Takayuki; Suzuki, Norio; Aonuma, Hiroshi

    2009-01-01

    We analyzed cases of lumbar nerve root compression at intervertebral foramina, by comparing 19 cases of foraminal stenosis (FS), and 38 cases of foraminal hernia (FH) with 21 cases of lumbar canal stenosis (LCS). Japan Orthopedic Association (JOA) scores, intervertebral disc degeneration, anatomical measurements of the nerve root foramina and the MRI findings were reviewed. The scores for pain in the lower extremities, and walking ability were both lowest in the FS group. The scores for low back pain, lower extremities, and sensory disturbances were lowest in the FH group. Anterior-posterior diameters of the nerve root foramina were smaller in the FS group and FH group than in the LCS group. More degenerated discs and short length of upper part of the nerve root foramina were seen in FS group than in the other groups. The MRI images of so-called black out nerve root foramina were positive in 63.6% of FS cases, 75% of FH cases. (author)

  11. Characteristics of Rathke's cleft cyst in MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Tominaga, Jun-ya; Higano, Shuichi; Takahashi, Shoki [Tohoku Univ., Sendai (Japan). School of Medicine

    2003-04-01

    The purpose of this study was symptoms, macroscopic appearances and microscopic findings of Rathke's cleft cysts with magnetic resonance (MR) imaging. We analyzed the data from 31 patients with pathologically confirmed Rathke's cleft cysts. MR appearances were evaluated on T{sub 1}WI, T{sub 2}WI and contrast T{sub 1}WI. Symptoms, macroscopic appearances and pathological findings were obtained from available medical records. We analyzed the images according to the following criteria: findings on the location and shape of the lesions and form of the lesional wall; the relationship between the maximum diameter of the lesions and symptoms; the relationship between MR and macroscopic appearance; the sites of adjacent contrast enhancement. The lesions were located mostly in both the intrasellar and suprasellar regions for a total of 87%. All lesions revealed either an oval or dumbbell shape with a smooth lesional wall. When correlated with physical symptoms, asymptomatic cases were associated with smaller lesions, while visual disturbances and dizziness were associated with relatively larger lesions. MR lesion signal intensity was related to the content of macroscopic appearance to some degree: the selected lesions showed shortening of T{sub 1} and T{sub 2} relaxation times in relation to the increase in protein concentration. This should have been macro-scopically reflected in the color and turbidity of the liquid within the cyst. Adjacent contrast enhancement around the lesion was found at various sites, but anterior enhancement was most frequent. Circumferential enhancement was revealed to be derived from inflammatory changes. Rathke's cleft cyst exhibits a varied MR signal. It may be difficult to differentiate from craniopharyngioma from the intensity alone. (author)

  12. Imaging in gynecological disease (9): clinical and ultrasound characteristics of tubal cancer.

    Science.gov (United States)

    Ludovisi, M; De Blasis, I; Virgilio, B; Fischerova, D; Franchi, D; Pascual, M A; Savelli, L; Epstein, E; Van Holsbeke, C; Guerriero, S; Czekierdowski, A; Zannoni, G; Scambia, G; Jurkovic, D; Rossi, A; Timmerman, D; Valentin, L; Testa, A C

    2014-03-01

    To describe clinical history and ultrasound findings in patients with tubal carcinoma. Patients with a histological diagnosis of tubal cancer who had undergone preoperative ultrasound examination were identified from the databases of 13 ultrasound centers. The tumors were described by the principal investigator at each contributing center on the basis of ultrasound images, ultrasound reports and research protocols (when applicable) using the terms and definitions of the International Ovarian Tumor Analysis (IOTA) group. In addition, three authors reviewed together all available digital ultrasound images and described them using subjective evaluation of gray-scale and color Doppler ultrasound findings. We identified 79 women with a histological diagnosis of primary tubal cancer, 70 of whom (89%) had serous carcinomas and 46 (58%) of whom presented at FIGO stage III. Forty-nine (62%) women were asymptomatic (incidental finding), whilst the remaining 30 complained of abdominal bloating or pain. Fifty-three (67%) tumors were described as solid at ultrasound examination, 14 (18%) as multilocular solid, 10 (13%) as unilocular solid and two (3%) as unilocular. No tumor was described as a multilocular mass. Most tumors (70/79, 89%) were moderately or very well vascularized on color or power Doppler ultrasound. Normal ovarian tissue was identified adjacent to the tumor in 51% (39/77) of cases. Three types of ultrasound appearance were identified as being typical of tubal carcinoma using pattern recognition: a sausage-shaped cystic structure with solid tissue protruding into it like a papillary projection (11/62, 18%); a sausage-shaped cystic structure with a large solid component filling part of the cyst cavity (13/62, 21%); an ovoid or oblong completely solid mass (36/62, 58%). A well vascularized ovoid or sausage-shaped structure, either completely solid or with large solid component(s) in the pelvis, should raise the suspicion of tubal cancer, especially if normal

  13. Can technical characteristics predict clinical performance in PET/CT imaging? A correlation study for thyroid cancer diagnosis

    Science.gov (United States)

    Kallergi, Maria; Menychtas, Dimitrios; Georgakopoulos, Alexandros; Pianou, Nikoletta; Metaxas, Marinos; Chatziioannou, Sofia

    2013-03-01

    The purpose of this study was to determine whether image characteristics could be used to predict the outcome of ROC studies in PET/CT imaging. Patients suspected for recurrent thyroid cancer underwent a standard whole body (WB) examination and an additional high-resolution head-and-neck (HN) F18-FDG PET/CT scan. The value of the latter was determined with an ROC study, the results of which showed that the WB+HN combination was better than WB alone for thyroid cancer detection and diagnosis. Following the ROC experiment, the WB and HN images of confirmed benign or malignant thyroid disease were analyzed and first and second order textural features were determined. Features included minimum, mean, and maximum intensity, as well as contrast in regions of interest encircling the thyroid lesions. Lesion size and standard uptake values (SUV) were also determined. Bivariate analysis was applied to determine relationships between WB and HN features and between observer ROC responses and the various feature values. The two sets showed significant associations in the values of SUV, contrast, and lesion size. They were completely different when the intensities were considered; no relationship was found between the WB minimum, maximum, and mean ROI values and their HN counterparts. SUV and contrast were the strongest predictors of ROC performance on PET/CT examinations of thyroid cancer. The high resolution HN images seem to enhance these relationships but without a single dramatic effect as was projected from the ROC results. A combination of features from both WB and HN datasets may possibly be a more robust predictor of ROC performance.

  14. Superior Canal Dehiscence Syndrome: Lessons from the First 20 Years

    Directory of Open Access Journals (Sweden)

    Bryan K. Ward

    2017-04-01

    Full Text Available Superior semicircular canal dehiscence syndrome was first reported by Lloyd Minor and colleagues in 1998. Patients with a dehiscence in the bone overlying the superior semicircular canal experience symptoms of pressure or sound-induced vertigo, bone conduction hyperacusis, and pulsatile tinnitus. The initial series of patients were diagnosed based on common symptoms, a physical examination finding of eye movements in the plane of the superior semicircular canal when ear canal pressure or loud tones were applied to the ear, and high-resolution computed tomography imaging demonstrating a dehiscence in the bone over the superior semicircular canal. Research productivity directed at understanding better methods for diagnosing and treating this condition has substantially increased over the last two decades. We now have a sound understanding of the pathophysiology of third mobile window syndromes, higher resolution imaging protocols, and several sensitive and specific diagnostic tests. Furthermore, we have a treatment (surgical occlusion of the superior semicircular canal that has demonstrated efficacy. This review will highlight some of the fundamental insights gained in SCDS, propose diagnostic criteria, and discuss future research directions.

  15. Imaging in gynecological disease. 10: Clinical and ultrasound characteristics of decidualized endometriomas surgically removed during pregnancy.

    Science.gov (United States)

    Mascilini, F; Moruzzi, C; Giansiracusa, C; Guastafierro, F; Savelli, L; De Meis, L; Epstein, E; Timor-Tritsch, I E; Mailath-Pokorny, M; Ercoli, A; Exacoustos, C; Benacerraf, B R; Valentin, L; Testa, A C

    2014-09-01

    To describe the clinical history and ultrasound findings in women with decidualized endometriomas surgically removed during pregnancy. In this retrospective study, women with a histological diagnosis of decidualized endometrioma during pregnancy who had undergone preoperative ultrasound examination were identified from the databases of seven ultrasound centers. The ultrasound appearance of the tumors was described on the basis of ultrasound images, ultrasound reports and research protocols (when applicable) by one author from each center using the terms and definitions of the International Ovarian Tumor Analysis (IOTA) group. In addition, two authors reviewed together available digital ultrasound images and used pattern recognition to describe the typical ultrasound appearance of decidualized endometriomas. Eighteen eligible women were identified. Median age was 34 (range, 20-43) years. Median gestational age at surgical removal of the decidualized endometrioma was 18 (range, 11-41) weeks. Seventeen women (94%) were asymptomatic and one presented with pelvic pain. In three of the 18 women an ultrasound diagnosis of endometrioma had been made before pregnancy. The original ultrasound examiner was uncertain whether the mass was benign or malignant in 10 (56%) women and suggested a diagnosis of benignity in nine (50%) women, borderline in eight women (44%), and invasive malignancy in one (6%) woman. Seventeen decidualized endometriomas contained a papillary projection, and in 16 of these at least one of the papillary projections was vascularized at power or color Doppler examination. The number of cyst locules varied between one (n = 11) and four. No woman had ascites. When using pattern recognition, most decidualized endometriomas (14/17, 82%) were described as manifesting vascularized rounded papillary projections with a smooth contour in an ovarian cyst with one or a few cyst locules and ground-glass or low-level echogenicity of the cyst fluid. Rounded vascularized

  16. Neuropsychiatric symptoms and PET imaging characteristics in patients with Parkinson-plus syndromes

    Directory of Open Access Journals (Sweden)

    Miao ZHANG

    2017-01-01

    Full Text Available Objective To explore the neuropsychiatric symptoms and 18F-fluoro-2-deoxy-D-glucose (18F-FDG PET imaging features of Parkinson-plus syndromes. Methods There were 8 patients with probable Parkinson-plus syndromes, including one case of multiple system atrophy-cerebellar predominant (MSA-C, 4 cases of progressive supranuclear palsy (PSP, one case of corticobasal ganglionic degeneration (CBD and 2 cases of dementia with Lewy bodies (DLB. Mini-Mental State Examination (MMSE and Montreal Cognitive Assessment (MoCA were used to evaluate cognitive function, Neuropsychiatric Inventory (NPI was used to evaluate neuropsychiatric behaviors, and Hamilton Depression Rating Scale-21 Items (HAMD-21 was used to evaluate the emotional state of patients. Results One MSA-C patient showed only anxiety. Four PSP patients showed different degrees of cognitive disorders, of whom 3 cases also presented obvious depression, anxiety, irritability and sleep disorders. One case of CBD showed dysfunction in executive function, visual spatial ability, verbal function, attention and orientation, as well as depression, anxiety, irritability and sleep disorders. Two cases of DLB were found unable to copy pentagon in MMSE chart or draw a circle in Clock Drawing Test (CDT, and they also presented hallucination, depression and indifference. As for the result of 18F-FDG PET, one MSA-C patient showed cerebellarglucose hypometabolism; 4 PSP patients showed hypometabolism in bilateral symmetrical frontal lobes, anterior cingulate gyrus and parietal lobe, especially in thalamus, basal ganglia region and brain stem; one case of CBD showed hypometabolism in right lateral fronto-temporo-parieto-occipital lobes, left lateral parietal lobe, bilateral cingulate gyri and precuneus; 2 cases of DLB showed hypometabolism in bilateral temporo-occipital lobes. Conclusions Patients with early Parkinson-plus syndromes are easily misdiagnosed as mental illness and delayed treatment, in addition, their

  17. Superior Canal Dehiscence Syndrome Affecting 3 Families.

    Science.gov (United States)

    Heidenreich, Katherine D; Kileny, Paul R; Ahmed, Sameer; El-Kashlan, Hussam K; Melendez, Tori L; Basura, Gregory J; Lesperance, Marci M

    2017-07-01

    Superior canal dehiscence syndrome (SCDS) is an increasingly recognized cause of hearing loss and vestibular symptoms, but the etiology of this condition remains unknown. To describe 7 cases of SCDS across 3 families. This retrospective case series included 7 patients from 3 different families treated at a neurotology clinic at a tertiary academic medical center from 2010 to 2014. Patients were referred by other otolaryngologists or were self-referred. Each patient demonstrated unilateral or bilateral SCDS or near dehiscence. Clinical evaluation involved body mass index calculation, audiometry, cervical vestibular evoked myogenic potential testing, electrocochleography, and multiplanar computed tomographic (CT) scan of the temporal bones. Zygosity testing was performed on twin siblings. The diagnosis of SCDS was made if bone was absent over the superior semicircular canal on 2 consecutive CT images, in addition to 1 physiologic sign consistent with labyrinthine dehiscence. Near dehiscence was defined as absent bone on only 1 CT image but with symptoms and at least 1 physiologic sign of labyrinthine dehiscence. A total of 7 patients (5 female and 2 male; age range, 8-49 years) from 3 families underwent evaluation. Family A consisted of 3 adult first-degree relatives, of whom 2 were diagnosed with SCDS and 1 with near dehiscence. Family B included a mother and her child, both of whom were diagnosed with unilateral SCDS. Family C consisted of adult monozygotic twins, each of whom was diagnosed with unilateral SCDS. For all cases, dehiscence was located at the arcuate eminence. Obesity alone did not explain the occurrence of SCDS because 5 of the 7 cases had a body mass index (calculated as weight in kilograms divided by height in meters squared) less than 30.0. Superior canal dehiscence syndrome is a rare, often unrecognized condition. This report of 3 multiplex families with SCDS provides evidence in support of a potential genetic contribution to the etiology

  18. Characteristics of Gamma-Ray Loud Blazars in the VLBA Imaging and Polarimetry Survey

    Science.gov (United States)

    Linford, J. D.; Taylor, G. B.; Romani, R. W.; Healey, S. E.; Helmboldt, J. F.; Readhead, A. C.; Reeves, R.; Richards, J. L.; Cotter, G.

    2010-01-01

    The radio properties of blazars detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been observed as part of the VLBA Imaging and Polarimetry Survey. This large, flux-limited sample of active galactic nuclei (AGNs) provides insights into the mechanism that produces strong gamma-ray emission. At lower flux levels, radio flux density does not directly correlate with gamma-ray flux. We find that the LAT-detected BL Lac objects tend to be similar to the non-LAT BL Lac objects, but that the LAT-detected FSRQs are often significantly different from the non-LAT FSRQs. The differences between the gamma-ray loud and quiet FSRQS can be explained by Doppler boosting; these objects appear to require larger Doppler factors than those of the BL Lac objects. It is possible that the gamma-ray loud FSRQs are fundamentally different from the gamma-ray quiet FSRQs. Strong polarization at the base of the jet appears to be a signature for gamma-ray loud AGNs.

  19. Cognitive Impairment and Brain Imaging Characteristics of Patients with Congenital Cataracts, Facial Dysmorphism, Neuropathy Syndrome

    Directory of Open Access Journals (Sweden)

    Teodora Chamova

    2015-01-01

    Full Text Available Congenital cataracts, facial dysmorphism, neuropathy (CCFDN syndrome is a complex autosomal recessive multisystem disorder. The aim of the current study is to evaluate the degree of cognitive impairment in a cohort of 22 CCFDN patients and its correlation with patients’ age, motor disability, ataxia, and neuroimaging changes. Twenty-two patients with genetically confirmed diagnosis of CCFDN underwent a detailed neurological examination. Verbal and nonverbal intelligence, memory, executive functions, and verbal fluency wеre assessed in all the patients aged 4 to 47 years. Brain magnetic resonance imaging was performed in 20 affected patients. Eighteen affected were classified as having mild intellectual deficit, whereas 4 had borderline intelligence. In all psychometric tests, evaluating different cognitive domains, CCFDN patients had statistically significant lower scores when compared to the healthy control group. All cognitive domains seemed equally affected. The main abnormalities on brain MRI found in 19/20 patients included diffuse cerebral atrophy, enlargement of the lateral ventricles, and focal lesions in the subcortical white matter, different in number and size, consistent with demyelination more pronounced in the older CCFDN patients. The correlation analysis of the structural brain changes and the cognitive impairment found a statistically significant correlation only between the impairment of short-term verbal memory and the MRI changes.

  20. Effect of birefringence of lens material on polarization status and optical imaging characteristics

    Science.gov (United States)

    Kim, Wan-Chin; Park, No-Cheol

    2018-04-01

    In most cases of molding with glass or optical polymers, it is expected that there will be birefringence caused by the internal mechanical stresses remaining in the molding material. The distribution of the residual stress can be annealed by slow cooling, but this approach is disadvantageous with respect to the shape accuracy and manufacturing time. In this study, we propose an analytical model to calculate the diffracted field near the focal plane by considering two primary parameters, the orientation angle of the fast axis and the path difference. In order to verify the reliability of the analytical model, we compared the measured beam spot of the F-theta lens of the laser scanning unit (LSU) with the analytical result. In addition, we analyzed the calculated result from the perspective of the polarization status in the exit pupil. The proposed analysis method can be applied to enhance the image quality for cases in which birefringence occurs in a lens material by suitably modeling the amplitude and phase of the incident light flux.

  1. Epithelioid hemangioma of bone: radiologic and magnetic resonance imaging characteristics with histopathological correlation

    Energy Technology Data Exchange (ETDEWEB)

    Schenker, Kathleen; Blumer, Steven [Nemours/Alfred I. duPont Hospital for Children, Department of Radiology, Wilmington, DE (United States); Jaramillo, Diego [Nicklaus Children' s Hospital, Department of Radiology, Miami, FL (United States); Treece, Amanda L. [University of Colorado School of Medicine, Departments of Pathology and Laboratory Medicine, Children' s Hospital Colorado, Aurora, CO (United States); Bhatia, Aashim [Monroe Carell Jr. Children' s Hospital at Vanderbilt, Department of Radiology, Nashville, TN (United States)

    2017-11-15

    Epithelioid hemangioma is a rare vascular tumor that can occur in soft tissues or bone. The tumor is part of a spectrum of vascular tumors that also includes epithelioid hemangioendothelioma and angiosarcoma. When involving the bone, the tumor usually involves the metaphysis or diaphysis of the long tubular bones and most commonly occurs in adults. It has been rarely reported in pediatric patients, and in these reported patients, the tumor primarily involves the epiphysis. To review three cases of epithelioid hemangioma of bone occurring in pediatric patients involving the epiphysis and to explore the imaging features of this tumor. Retrospectively review three cases of epithelioid hemangioma occurring in skeletally immature patients. These tumors primarily involved the epiphyses or epiphyseal equivalent bones. One lesion was centered in the metaphysis but extended to the epiphysis. These are three cases presenting in an unusual location and at an unusual age. Epithelioid hemangioma, though rare, can occur in pediatric patients and appears to involve the epiphyses in these patients. This is in contrast to the usual age and location reported. Epithelioid hemangioma may be considered for an epiphyseal lesion in a skeletally immature patient. (orig.)

  2. Intrusive images in psychological disorders: characteristics, neural mechanisms, and treatment implications.

    Science.gov (United States)

    Brewin, Chris R; Gregory, James D; Lipton, Michelle; Burgess, Neil

    2010-01-01

    Involuntary images and visual memories are prominent in many types of psychopathology. Patients with posttraumatic stress disorder, other anxiety disorders, depression, eating disorders, and psychosis frequently report repeated visual intrusions corresponding to a small number of real or imaginary events, usually extremely vivid, detailed, and with highly distressing content. Both memory and imagery appear to rely on common networks involving medial prefrontal regions, posterior regions in the medial and lateral parietal cortices, the lateral temporal cortex, and the medial temporal lobe. Evidence from cognitive psychology and neuroscience implies distinct neural bases to abstract, flexible, contextualized representations (C-reps) and to inflexible, sensory-bound representations (S-reps). We revise our previous dual representation theory of posttraumatic stress disorder to place it within a neural systems model of healthy memory and imagery. The revised model is used to explain how the different types of distressing visual intrusions associated with clinical disorders arise, in terms of the need for correct interaction between the neural systems supporting S-reps and C-reps via visuospatial working memory. Finally, we discuss the treatment implications of the new model and relate it to existing forms of psychological therapy.

  3. Analysis of industrial flame characteristics and constancy study using image processing technique

    Directory of Open Access Journals (Sweden)

    Bibhuti Bhusan Samantaray

    2015-12-01

    Full Text Available The study of characterizing and featuring different kinds of flames has become more important than ever in order to increase combustion efficiency and decrease particulate emissions, especially since the study of industrial flames requires more attention. In the present work, different kinds of combustion flames have been characterized by means of digital image processing (DIP in a 500 kW PF pilot swirl burner. A natural gas flame and a set of pulverized fuel flames of coal and biomass have been comparatively analyzed under co-firing conditions. Through DIP, statistical and spectral features of the flame have been extracted and graphically represented as two-dimensional distributions covering the root flame area. Their study and comparison leads to different conclusions about the flame behavior and the effect of co-firing coal and biomass in pulverized fuel flames. Higher oscillation levels in co-firing flames versus coal flames and variations in radiation regimen were noticed when different biomasses are blended with coal and brought under attention.

  4. Integration of Satellite Tracking Data and Satellite Images for Detailed Characteristics of Wildlife Habitats

    Science.gov (United States)

    Dobrynin, D. V.; Rozhnov, V. V.; Saveliev, A. A.; Sukhova, O. V.; Yachmennikova, A. A.

    2017-12-01

    Methods of analysis of the results got from satellite tracking of large terrestrial mammals differ in the level of their integration with additional geographic data. The reliable fine-scale cartographic basis for assessing specific wildlife habitats can be developed through the interpretation of multispectral remote sensing data and extrapolation of the results to the entire estimated species range. Topographic maps were ordinated according to classified features using self-organizing maps (Kohonen's SOM). The satellite image of the Ussuriiskyi Nature Reserve area was interpreted for the analysis of movement conditions for seven wild Amur tigers ( Panthera tigris altaica) equipped with GPS collars. 225 SOM classes for cartographic visualization are sufficient for the detailed mapping of all natural complexes that were identified as a result of interpretation. During snow-free periods, tigers preferred deciduous and shrub associations at lower elevations, as well as mixed forests in the valleys of streams that are adjacent to sparse forests and shrub watershed in the mountain ranges; during heavy snow periods, the animals preferred the entire range of plant communities in different relief types, except for open sites in meadows and abandoned fields at foothills. The border zones of different biotopes were typically used by the tigers during all seasons. Amur tigers preferred coniferous forests for long-term movements.

  5. Affective evaluation of food images according to stimulus and subject characteristics.

    Science.gov (United States)

    Padulo, C; Carlucci, L; Marzoli, D; Manippa, V; Tommasi, L; Saggino, A; Puglisi-Allegra, S; Brancucci, A

    2018-04-17

    The food-rich environment in which we live makes the regulation of food choices a very complex phenomenon determined by many factors, as well as their interactions. Much evidence suggests that the sensory perception of food can be considered as a central factor affecting individual food choices. Despite this, the approaches used to study the various food aspects usually do not distinguish between different types of food. In the present study, a large and heterogeneous sample of 1149 participants aged 7-90 years was asked to judge food images that were labelled differently (i.e. Raw versus Cooked, Natural versus Transformed and Simple versus Complex) with respect to arousal, valence, typicality and familiarity. We observed that, across food dimensions (i.e., Raw versus Cooked, Natural versus Transformed and Simple versus Complex), arousal, valence and typicality judgments were principally affected by a subjective hunger level and gender (and their interaction) and, to a lesser extent, by age. As a whole, our findings suggest that the level of transformation (which includes cooking) and the complexity of a foodstuff could at least partially affect food processing, entailing that future research should also address these features. © 2018 The British Dietetic Association Ltd.

  6. Using spectral characteristics to interpret auroral imaging in the 731.9 nm O+ line

    Directory of Open Access Journals (Sweden)

    H. Dahlgren

    2008-07-01

    Full Text Available Simultaneous observations were made of dynamic aurora during substorm activity on 26 January 2006 with three high spatial and temporal resolution instruments: the ASK (Auroral Structure and Kinetics instrument, SIF (Spectrographic Imaging Facility and ESR (EISCAT Svalbard Radar, all located on Svalbard (78° N, 16.2° E. One of the narrow field of view ASK cameras is designed to detect O+ ion emission at 731.9 nm. From the spectrographic data we have been able to determine the amount of contaminating N2 and OH emission detected in the same filter. This is of great importance to further studies using the ASK instrument, when the O+ ion emission will be used to detect flows and afterglows in active aurora. The ratio of O+ to N2 emission is dependent on the energy spectra of electron precipitation, and was found to be related to changes in the morphology of the small-scale aurora. The ESR measured height profiles of electron densities, which allowed estimates to be made of the energy spectrum of the precipitation during the events studied with optical data from ASK and SIF. It was found that the higher energy precipitation corresponded to discrete and dynamic features, including curls, and low energy precipitation corresponded to auroral signatures that were dominated by rays. The evolution of these changes on time scales of seconds is of importance to theories of auroral acceleration mechanisms.

  7. CHARACTERISTICS OF GAMMA-RAY LOUD BLAZARS IN THE VLBA IMAGING AND POLARIMETRY SURVEY

    International Nuclear Information System (INIS)

    Linford, J. D.; Taylor, G. B.; Romani, R. W.; Healey, S. E.; Helmboldt, J. F.; Readhead, A. C. S.; Reeves, R.; Richards, J. L.; Cotter, G.

    2011-01-01

    The radio properties of blazars detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been observed as part of the VLBA Imaging and Polarimetry Survey. This large, flux-limited sample of active galactic nuclei (AGNs) provides insights into the mechanism that produces strong γ-ray emission. At lower flux levels, radio flux density does not directly correlate with γ-ray flux. We find that the LAT-detected BL Lac objects tend to be similar to the non-LAT BL Lac objects, but that the LAT-detected FSRQs are often significantly different from the non-LAT FSRQs. The differences between the γ-ray loud and quiet FSRQs can be explained by Doppler boosting; these objects appear to require larger Doppler factors than those of the BL Lac objects. It is possible that the γ-ray loud FSRQs are fundamentally different from the γ-ray quiet FSRQs. Strong polarization at the base of the jet appears to be a signature for γ-ray loud AGNs.

  8. Characteristics of Gamma-ray Loud Blazars in the VLBA Imaging and Polarimetry Survey

    Science.gov (United States)

    Linford, J. D.; Taylor, G. B.; Romani, R. W.; Healey, S. E.; Helmboldt, J. F.; Readhead, A. C. S.; Reeves, R.; Richards, J. L.; Cotter, G.

    2011-01-01

    The radio properties of blazars detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been observed as part of the VLBA Imaging and Polarimetry Survey. This large, flux-limited sample of active galactic nuclei (AGNs) provides insights into the mechanism that produces strong γ-ray emission. At lower flux levels, radio flux density does not directly correlate with γ-ray flux. We find that the LAT-detected BL Lac objects tend to be similar to the non-LAT BL Lac objects, but that the LAT-detected FSRQs are often significantly different from the non-LAT FSRQs. The differences between the γ-ray loud and quiet FSRQs can be explained by Doppler boosting; these objects appear to require larger Doppler factors than those of the BL Lac objects. It is possible that the γ-ray loud FSRQs are fundamentally different from the γ-ray quiet FSRQs. Strong polarization at the base of the jet appears to be a signature for γ-ray loud AGNs.

  9. Characteristic MR image finding of squatting exercise-induced rhabdomyolysis of the thigh muscles.

    Science.gov (United States)

    Yeon, Eung K; Ryu, Kyung N; Kang, Hye J; Yoon, So H; Park, So Y; Park, Ji S; Jin, Wook

    2017-04-01

    To describe the characteristic MRI appearance of squatting-induced rhabdomyolysis involving the thigh muscles. This study consisted of 10 cases obtained at 3 institutions from 2005 to 2015. A retrospective review was performed to obtain clinical information and MR scans for rhabdomyolysis of the thigh muscles. MRI was analyzed according to the distribution and degree of muscle involvement; the degree was assessed and graded as normal, mild or prominent. The mean patient age was 20.2 years (range, 15-24 years), and 7 of the 10 patients were male. All patients had history of excessive squatting action, suffered clinically from bilateral thigh pain and were confirmed to have rhabdomyolysis through analysis of serum creatine kinase (CK) levels. All of the patients (10/10) exhibited diffuse mild to prominent degree involvement of the anterior thigh muscles according to fluid-sensitive MR sequences. Among the anterior thigh muscles, the rectus femoris was spared in 8 patients (8/10) and mild degree involved in 2 patients (2/10). Thus, no cases exhibited prominent degree involvement of the rectus femoris muscle. Preservation of the rectus femoris muscle on MRI in squatting-induced rhabdomyolysis may be useful for differentiating rhabdomyolysis from other aetiologies. Advances in knowledge: Preservation of rectus femoris on MRI is distinguishable finding in squatting-induced rhabdomyolysis and reflects the functional anatomy of anterior thigh muscles.

  10. Chest imaging characteristics of hand-foot-mouth disease in children

    International Nuclear Information System (INIS)

    Ma Bo; Chen Ruigang; Dou Shewei; Zhu Xiaonian; Shi Dapeng

    2010-01-01

    Objective: To study radiological characteristics of hand-foot-mouth disease (HFMD) in children. Methods: The chest X-ray films of 1295 children patients of HFMD were analyzed, for the general X-ray manifestations and the evolution. Results: A total of 1427 films was obtained from all patients, in which 1203 cases were normal and 224 cases were abnormal. The interstitial changes characterized the abnormal group, mainly as increased and vague lung markings, increased hilar shadows (137 cases). The parenchyma changes appeared as patchy exudative shadows(49 cases). Short-term dynamic observation was applied in 62 cases, 38 cases pulmonary disease progression manifested as normal and the interstitial type changing into the parenchyma type and the mixed type, the localized type changing into the diffuse type. Conclusions: Most children patients of' HFMD showed normal chest films, while the abnormal patients were characterized by interstitial and parenchyma pulmonary edema. Serial chest X-ray examination and short-term dynamic observation were important to identify the severe cases and assess patients' condition. (authors)

  11. Facial Nerve Paralysis due to a Pleomorphic Adenoma with the Imaging Characteristics of a Facial Nerve Schwannoma.

    Science.gov (United States)

    Nader, Marc-Elie; Bell, Diana; Sturgis, Erich M; Ginsberg, Lawrence E; Gidley, Paul W

    2014-08-01

    Background Facial nerve paralysis in a patient with a salivary gland mass usually denotes malignancy. However, facial paralysis can also be caused by benign salivary gland tumors. Methods We present a case of facial nerve paralysis due to a benign salivary gland tumor that had the imaging characteristics of an intraparotid facial nerve schwannoma. Results The patient presented to our clinic 4 years after the onset of facial nerve paralysis initially diagnosed as Bell palsy. Computed tomography demonstrated filling and erosion of the stylomastoid foramen with a mass on the facial nerve. Postoperative histopathology showed the presence of a pleomorphic adenoma. Facial paralysis was thought to be caused by extrinsic nerve compression. Conclusions This case illustrates the difficulty of accurate preoperative diagnosis of a parotid gland mass and reinforces the concept that facial nerve paralysis in the context of salivary gland tumors may not always indicate malignancy.

  12. Television images and probable posttraumatic stress disorder after September 11: the role of background characteristics, event exposures, and perievent panic.

    Science.gov (United States)

    Ahern, Jennifer; Galea, Sandro; Resnick, Heidi; Vlahov, David

    2004-03-01

    Television viewing has been associated with posttraumatic stress disorder (PTSD) symptoms after disasters and traumas; we examined characteristics that may explain this association among New Yorkers after September 11, 2001. Among 2001 respondents to a random-digit dial telephone survey conducted 4 months after September 11, people who viewed more television images in the 7 days after September 11 had more probable PTSD. People in the highest third of viewing had a 2.32 times greater odds of probable PTSD after September 11 compared with people in the lowest third of viewing; after adjustment for explanatory variables, the relative odds of probable PTSD were 1.66. Adjustment for perievent panic accounted for 44% of the reduction in association between television and probable PTSD, suggesting that perievent emotional reactions may play an important role in the television and psychopathology association. Television may merit consideration as a potential exposure to a traumatic event.

  13. A generalized ray-tracing procedure for an atmospheric Cherenkov imaging telescope and optical characteristics of the TACTIC light collector

    International Nuclear Information System (INIS)

    Tickoo, A.K.; Suthar, R.L.; Koul, R.; Sapru, M.L.; Kumar, N.; Kaul, C.L.; Yadav, K.K.; Thoudam, S.; Kaul, S.K.; Venugopal, K.; Kothari, M.; Goyal, H.C.; Chandra, P.; Dhar, V.K.; Rannot, R.C.; Koul, M.K.; Kaul, S.R.

    2005-01-01

    A generalized ray-tracing procedure has been developed, which facilitates the design of a multimirror-based light collector used in atmospheric Cherenkov telescopes. This procedure has been employed to study the optical characteristics of the 3.5 m diameter light collector of the TACTIC Imaging telescope. Comparison of the measured point-spread function of the light collector with the simulated performance of ideal Davies-Cotton and paraboloid designs has been made to determine an optimum arrangement of the 34 spherical mirror facets used in the telescope to obtain the best possible point-spread function. A description of the ray-tracing subroutine used for processing CORSIKA-generated Cherenkov data, required for carrying out Monte-Carlo simulation studies, is also discussed in the paper

  14. The correlation between the imaging characteristics of hamstring injury and time required before returning to sports: a literature review.

    Science.gov (United States)

    Svensson, Kjell; Alricsson, Marie; Eckerman, Mattias; Magounakis, Theofilos; Werner, Suzanne

    2016-06-01

    Injuries to the hamstring muscles are common in athletes. Track and field, Australian football, American football and soccer are examples of sports where hamstring injuries are the most common. The purpose of this study was to investigate whether there is a correlation between a hamstring injury prognosis and its characteristics of imaging parameters. The literature search was performed in the databases PubMed and CINAHL, and eleven articles were included. Seven out of the 11 articles showed a correlation between the size of the hamstring injury and length of time required before returning to sports. Different authors have reported contrasting results about length of time required before returning to sports due to location of injury within specific muscle. Majority of the articles found hamstring strain correlated to an extended amount of time required before returning to sports.

  15. Are Study and Journal Characteristics Reliable Indicators of "Truth" in Imaging Research?

    Science.gov (United States)

    Frank, Robert A; McInnes, Matthew D F; Levine, Deborah; Kressel, Herbert Y; Jesurum, Julia S; Petrcich, William; McGrath, Trevor A; Bossuyt, Patrick M

    2018-04-01

    Purpose To evaluate whether journal-level variables (impact factor, cited half-life, and Standards for Reporting of Diagnostic Accuracy Studies [STARD] endorsement) and study-level variables (citation rate, timing of publication, and order of publication) are associated with the distance between primary study results and summary estimates from meta-analyses. Materials and Methods MEDLINE was searched for meta-analyses of imaging diagnostic accuracy studies, published from January 2005 to April 2016. Data on journal-level and primary-study variables were extracted for each meta-analysis. Primary studies were dichotomized by variable as first versus subsequent publication, publication before versus after STARD introduction, STARD endorsement, or by median split. The mean absolute deviation of primary study estimates from the corresponding summary estimates for sensitivity and specificity was compared between groups. Means and confidence intervals were obtained by using bootstrap resampling; P values were calculated by using a t test. Results Ninety-eight meta-analyses summarizing 1458 primary studies met the inclusion criteria. There was substantial variability, but no significant differences, in deviations from the summary estimate between paired groups (P > .0041 in all comparisons). The largest difference found was in mean deviation for sensitivity, which was observed for publication timing, where studies published first on a topic demonstrated a mean deviation that was 2.5 percentage points smaller than subsequently published studies (P = .005). For journal-level factors, the greatest difference found (1.8 percentage points; P = .088) was in mean deviation for sensitivity in journals with impact factors above the median compared with those below the median. Conclusion Journal- and study-level variables considered important when evaluating diagnostic accuracy information to guide clinical decisions are not systematically associated with distance from the truth

  16. Human middle longitudinal fascicle: segregation and behavioral-clinical implications of two distinct fiber connections linking temporal pole and superior temporal gyrus with the angular gyrus or superior parietal lobule using multi-tensor tractography.

    Science.gov (United States)

    Makris, N; Preti, M G; Wassermann, D; Rathi, Y; Papadimitriou, G M; Yergatian, C; Dickerson, B C; Shenton, M E; Kubicki, M

    2013-09-01

    The middle longitudinal fascicle (MdLF) is a major fiber connection running principally between the superior temporal gyrus and the parietal lobe, neocortical regions of great biological and clinical interest. Although one of the most prominent cerebral association fiber tracts, it has only recently been discovered in humans. In this high angular resolution diffusion imaging (HARDI) MRI study, we delineated the two major fiber connections of the human MdLF, by examining morphology, topography, cortical connections, biophysical measures, volume and length in seventy-four brains. These two fiber connections course together through the dorsal temporal pole and the superior temporal gyrus maintaining a characteristic topographic relationship in the mediolateral and ventrodorsal dimensions. As these pathways course towards the parietal lobe, they split to form separate fiber pathways, one following a ventrolateral trajectory and connecting with the angular gyrus and the other following a dorsomedial route and connecting with the superior parietal lobule. Based on the functions of their cortical affiliations, we suggest that the superior temporal-angular connection of the MdLF, i.e., STG(MdLF)AG plays a role in language and attention, whereas the superior temporal-superior parietal connection of the MdLF, i.e., STG(MdLF)SPL is involved in visuospatial and integrative audiovisual functions. Furthermore, the MdLF may have clinical implications in neurodegenerative disorders such as primary progressive aphasia, frontotemporal dementia, posterior cortical atrophy, corticobulbar degeneration and Alzheimer's disease as well as attention-deficit/hyperactivity disorder and schizophrenia.

  17. Ruptured superior gluteal artery pseudoaneurysm with hemorrhagic shock: Case report.

    Science.gov (United States)

    Corbacioglu, Kerem Seref; Aksel, Gokhan; Yildiz, Altan

    2016-03-01

    Pseudoaneurysm of the superior gluteal artery (SGA) is very rare and the most common causes are blunt or penetrating pelvic traumas. Although pseudoaneurysm can be asymptomatic at the time of initial trauma, it can be symptomatic weeks, months, even years after initial trauma. We present a case of a ruptured superior gluteal artery pseudoaneurysm with hemorrhagic shock twenty days after a bomb injury in the Syria civil war. In addition, we review the anatomy of the SGA, clinical presentation and pitfalls of pseudoaneurysm, and imaging and treatment options.

  18. Imaging Characteristics and Prevalence of Pancreatic Carcinoma in Kosovo During 2011-2015 - Diagnostic Method as Choice.

    Science.gov (United States)

    Dedushi, Kreshnike; Kabashi, Serbeze; Mucaj, Sefedin; Hasbahta, Gazmed; Ramadani, Naser; Hoxhaj, Astrit

    2016-06-01

    Pancreatic cancer is the 10(th)most common malignancy and the 4(th)largest cancer killer in adults. The purpose of this paper is to evaluate the number of cases presented with pancreatic carcinoma during the years 2011-2015, our experience of the imaging characteristics of pancreatic carcinoma. We evaluated prevalence of the pancreatic cancers, distant metastases and other local infiltration signs among the total cases of the pancreatic cancers diagnosed in the University Clinical Center of Kosovo, with the aim to compare these research findings to similar studies made in the developed countries. This is a retrospective research study done during the period of 2011-2015. This retrospective research study includes 362 patients recently diagnosed with pancreatic cancer, examined in the period of 2011-2015 at the University Clinical Center of Kosovo. The imaging diagnostics are performed with MSCT Sensation 64 Siemens, MSCT Emotion 6 Siemens, and 1.5T MRI Symphony Siemens, biopsy guide with MSCT Sensation 64 Siemens in the Radiologic Clinic of UCCK; while the histopathology diagnostics has been performed in Clinic of Pathology at UCCK and prevalence is taken from the number of cases Reported at the Institute of Oncology Institute of Statistics and NIPH (National Institute of Public Health of Kosovo). Out of a total of the 362 patients diagnosed with pancreas cancer, results is female 39.5% (n=143) and male 61.5% (n=219), report M: F (1: 1.6), 286 cases resulted in head and neck 79 % (n=286), 76 cases resulted in body and tail cancers (21%), distant metastases in first imaging modality were found in(n=155) patients 43 %, local infiltration was found in patients: gastric infiltration 15 % (n=54), duodenal and papilla infiltration 26% (n=94), local infiltration spleen 16% (n=57), local infiltration mesentery 43 % (n= 155), dilated biliary tree 34 % (n=123), regional lymph node infiltration 83 % (n= 300). Out of a total of the 362 patients diagnosed with pancreas cancer

  19. MR imaging characteristics of osteoradionecrosis of the pelvis after radiation therapy on gynecological tumors; Pelvine Osteoradionekrosen: Magnetresonanztomographische Charakteristika

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, J.; Abolmaali, N.D.; Jacobi, V.; Vogl, T.J. [Institut fuer Diagnostische u. Interventionelle Radiologie, Klinikum der J. W. Goethe-Universitaet, Frankfurt (Germany); Hoeller, U. [Staedtisches Krankenhaus Neukoelln, Berlin (Germany). Abt. Strahlentherapie; Schiemann, M.; Obert, K. [Klinikum der J. W. Goethe-Universitaet, Frankfurt (Germany). Klinik fuer Strahlentherapie und Onkologie

    2002-01-01

    Purpose: To describe MR imaging characteristics of osteoradionecrosis (ORN) of the pelvis as a result of radiation therapy (RT) on gynecological tumors. Material and Methods: Radiography, computed tomography (CT) and magnetic resonance imaging (MRI) were performed on 9 women (mean age 67.5 years) with gynecological tumors to identify ORN. T{sub 1}- and T{sub 2}-weighted sequences and contrast-enhanced t{sub 1}-weighted sequences with and without fat saturation were used. The patients began developing pain after the completion of RT indicating a possible ORN a which time MRI was performed. MR images were correlated with the results of clinical examinations. Results: Depending on the time elapsed after RT, ORN presented with different signal intensities. The acquired images suggested that signal changes in T{sub 2}-weighted images as well as the different enhancement behaviour of ORN could be dependent on the time elapsed after RT. Visualisation of the affected regions was best achieved with fat-saturated T{sub 1}-weighted sequences. CT showed increased density in the affected regions corresponding to osteosclerosis. In all cases the sacroiliac joint was affected, some times bilateraly. Conclusion: MRI is helpful in detecting and characterizing ORN. Changes in signal intensity, based on histopathological tissue changes could make a chronological classification possible. (orig.) [German] Zielsetzung: Evaluation MR-tomographischer Charakteristika pelviner Osteoradionekrosen (ORN) bei Patientinnen nach Strahlentherapie gynaekologischer Tumoren. Material und Methode: 9 Patientinnen (mittleres Alter: 67,5 Jahre) mit gynaekologischen Tumoren und gesicherten ORN wurden mit der Magnetresonanztomographie (MRT) untersucht. Die MRT wurde beim Auftreten von Beschwerden nach unterschiedlichen Zeiten nach Bestrahlungsabschluss durchgefuehrt und mit den Ergebnissen der klinischen Diagnostik korreliert. Ergebnisse: ORN kamen fuer MR in Abhaengigkeit vom Abstand zum Bestrahlungsende

  20. Bone lesions in Chinese POEMS syndrome patients: imaging characteristics and clinical implications.

    Science.gov (United States)

    Wang, Fengdan; Huang, Xufei; Zhang, Yan; Li, Jian; Zhou, Daobin; Jin, Zhengyu

    2016-01-01

    Objective. Bone lesion is crucial for diagnosing and management of polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, and skin change (POEMS) syndrome, a rare plasma cell disorder. This study is to compare the effectiveness of X-ray skeletal survey (SS) and computed tomography (CT) for detecting bone lesions in Chinese POEMS syndrome patients, and to investigate the relationship between bone lesion features and serum markers. Methods. SS and chest/abdomen/pelvic CT images of 38 Chinese patients (26 males, 12 females, aged 21-70 years) with POEMS syndrome recruited at our medical center between January 2013 and January 2015 were retrospectively analyzed. Bone lesions identified by CT were further categorized according to the size (10 mm) and appearance (osteosclerotic, lytic, mixed). The percentage of plasma cells in bone marrow smears, type of immunoglobulin, platelet (Plt), and levels of serum bone metabolic markers and inflammatory factors including alkaline phosphatase (ALP), calcium, phosphate, parathyroid hormone (PTH), beta-isomerized C-telopeptide (β-CTx), vascular endothelial growth factor (VEGF), and interleukin (IL)-6 levels were also recorded. Results. Of the 38 POEMS syndrome patients, the immunoglobulin heavy chain isotypes were IgA in 25 patients (65.8%; 25/38) and IgG in 13 patients (34.2%; 13/38), and the light chain isotypes were λ in 35 patients (92.1%; 35/38) and κ in 3 patients (7.9%; 3/38). There were 23 patients with thrombocytosis. More patients with bone lesions were detected by CT than by SS (97.4% vs. 86.8%). The most commonly affected location was the pelvis (89.5%), followed by the spine, clavicle/scapula/sternum/ribs, skull, and long bones. Of the 38 POEMS syndrome patients, 35 (94.6%) had osteosclerotic and 32 (86.5%) had mixed lesions. Osteosclerotic lesions were typically scattered, variable in size, and plaque-like, whereas mixed lesions were pouch-shaped or soup bubble-like with a clear sclerotic margin and were

  1. Bone lesions in Chinese POEMS syndrome patients: imaging characteristics and clinical implications

    Directory of Open Access Journals (Sweden)

    Fengdan Wang

    2016-08-01

    Full Text Available Objective. Bone lesion is crucial for diagnosing and management of polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, and skin change (POEMS syndrome, a rare plasma cell disorder. This study is to compare the effectiveness of X-ray skeletal survey (SS and computed tomography (CT for detecting bone lesions in Chinese POEMS syndrome patients, and to investigate the relationship between bone lesion features and serum markers. Methods. SS and chest/abdomen/pelvic CT images of 38 Chinese patients (26 males, 12 females, aged 21–70 years with POEMS syndrome recruited at our medical center between January 2013 and January 2015 were retrospectively analyzed. Bone lesions identified by CT were further categorized according to the size (10 mm and appearance (osteosclerotic, lytic, mixed. The percentage of plasma cells in bone marrow smears, type of immunoglobulin, platelet (Plt, and levels of serum bone metabolic markers and inflammatory factors including alkaline phosphatase (ALP, calcium, phosphate, parathyroid hormone (PTH, beta-isomerized C-telopeptide (β-CTx, vascular endothelial growth factor (VEGF, and interleukin (IL-6 levels were also recorded. Results. Of the 38 POEMS syndrome patients, the immunoglobulin heavy chain isotypes were IgA in 25 patients (65.8%; 25/38 and IgG in 13 patients (34.2%; 13/38, and the light chain isotypes were λ in 35 patients (92.1%; 35/38 and κ in 3 patients (7.9%; 3/38. There were 23 patients with thrombocytosis. More patients with bone lesions were detected by CT than by SS (97.4% vs. 86.8%. The most commonly affected location was the pelvis (89.5%, followed by the spine, clavicle/scapula/sternum/ribs, skull, and long bones. Of the 38 POEMS syndrome patients, 35 (94.6% had osteosclerotic and 32 (86.5% had mixed lesions. Osteosclerotic lesions were typically scattered, variable in size, and plaque-like, whereas mixed lesions were pouch-shaped or soup bubble-like with a clear sclerotic margin and were

  2. Septic pulmonary embolism caused by a Klebsiella pneumoniae liver abscess: clinical characteristics, imaging findings, and clinical courses

    Directory of Open Access Journals (Sweden)

    Deng-Wei Chou

    2015-06-01

    Full Text Available OBJECTIVES: Septic pulmonary embolism caused by a Klebsiella (K. pneumoniae liver abscess is rare but can cause considerable morbidity and mortality. However, clinical information regarding this condition is limited. This study was conducted to elucidate the full disease spectrum to improve its diagnosis and treatment. METHOD: We reviewed the clinical characteristics, imaging findings, and clinical courses of 14 patients diagnosed with septic pulmonary embolism caused by a K. pneumoniae liver abscess over a period of 9 years. RESULTS: The two most prevalent symptoms were fever and shortness of breath. Computed tomography findings included a feeding vessel sign (79%, nodules with or without cavities (79%, pleural effusions (71%, peripheral wedge-shaped opacities (64%, patchy ground-glass opacities (50%, air bronchograms within a nodule (36%, consolidations (21%, halo signs (14%, and lung abscesses (14%. Nine (64% of the patients developed severe complications and required intensive care. According to follow-up chest radiography, the infiltrates and consolidations were resolved within two weeks, and the nodular opacities were resolved within one month. Two (14% patients died of septic shock; one patient had metastatic meningitis, and the other had metastatic pericarditis. CONCLUSION: The clinical presentations ranged from insidious illness with fever and respiratory symptoms to respiratory failure and septic shock. A broad spectrum of imaging findings, ranging from nodules to multiple consolidations, was detected. Septic pulmonary embolism caused by a K. pneumoniae liver abscess combined with the metastatic infection of other vital organs confers a poor prognosis.

  3. [Constitute, imaging and auditory characteristics of pediatric patients with congenital malformations of inner ear in sensorineural hearing loss].

    Science.gov (United States)

    Li, Youjin; Yang, Jun; Li, Yun

    2011-01-01

    To analyze the constitute, imaging and auditory characteristics of pediatric patients with congenital malformations of inner ear in sensorineural hearing loss(SNHL). Imaging and auditory data of 125 cases (225 ears) in 860 pediatric patients with congenital SNHL who referred to ENT department of Shanghai Children Medical Center from February 2005 to January 2010 were retrospectively studied. Congenital malformations of inner ear accounted for 14.5% in 860 pediatric patients with congenital SNHL. Bilateral ear was involved in 98 cases (78.4%), unilateral in 27 cases (21.6%). One hundred and sixty-seven ears (74.2%) were identified as profound deafness, 36 ears (16%) severe deafness and 22 ears (9.8%) moderate deafness in 225 ears, respectively. In present group, large vestibular aqueduct (75.6%) was the most common and next was vestibular deformity (32%), then cochleovestibular deformity (23.1%). Mondini deformity (55.8%) was the most common and common cavity deformity (28.9%) next in cochleovestibular deformity. Profound deafness in cochlea involved congenital malformations of inner ear was significantly more than those in no cochlea involved malformations. The results are of importance for understanding the constitute of congenital malformations of inner ear in pediatric patients with congenital SNHL in China, for etiological diagnosis of congenital SNHL, for intervention including hearing aids or cochlear implant and prognosis.

  4. Characteristic signal changes in the pontine base on T2- and multishot diffusion-weighted images in spinocerebellar ataxia type 1

    International Nuclear Information System (INIS)

    Adachi, M.; Kawanami, T.; Ohshima, H.; Hosoya, T.

    2006-01-01

    The aim of the present study was to demonstrate characteristic signal changes of the pontine base on T2-weighted images of patients with SCA 1, and to elucidate the relationship between abnormal high-intensities of the pontine base on T2-weighted images and the findings on multishot diffusion-weighted images. We assessed abnormal signals of the pontine base on T2-weighted images from 50 controls and six patients with SCA 1 diagnosed by genetic analysis. At the same time, we evaluated the degeneration of the transverse pontine fibers in the pontine base by multishot diffusion-weighted imaging. A midline high-intensity was seen in the pontine base on T2-weighted images in two of the 50 controls and five of the six patients with SCA 1. The midline high-intensity had a sensitivity of 83.3% for patients and a specificity of 96.0% for controls. Multishot diffusion-weighted imaging demonstrated the degeneration - the amorphous-pattern signal - of the transverse pontine fibers in four (66.7%) of the six patients. In the other two patients, the zebra-pattern signal was seen in the pontine base. The midline high-intensity on T2-weighted images appears to be one of characteristic MRI findings of SCA 1. Multishot diffusion-weighted imaging suggested that the midline high-intensity should reflect the degeneration of the transverse pontine fibers. (orig.)

  5. Distal intersection tenosynovitis of the wrist: a lesser-known extensor tendinopathy with characteristic MR imaging features

    International Nuclear Information System (INIS)

    Parellada, Antoni J.; Gopez, Angela G.; Morrison, William B.; Sweet, Stephanie; Leinberry, Charles F.; Reiter, Sean B.; Kohn, Mark

    2007-01-01

    the constraining effect of the extensor retinaculum. These anatomical features determine the presence of characteristic MR imaging findings. (orig.)

  6. Distal intersection tenosynovitis of the wrist: a lesser-known extensor tendinopathy with characteristic MR imaging features

    Energy Technology Data Exchange (ETDEWEB)

    Parellada, Antoni J. [DII - Diagnostic Imaging, Inc., Philadelphia, PA (United States); Frankford Hospitals - Torresdale Campus, Department of Radiology, Philadelphia, PA (United States); Gopez, Angela G.; Morrison, William B. [Thomas Jefferson University, Department of Radiology, Philadelphia, PA (United States); Sweet, Stephanie [Thomas Jefferson University, Philadelphia Hand Center, Philadelphia, PA (United States); Leinberry, Charles F. [Thomas Jefferson University, Department of Orthopedic Surgery - Hand Surgery, Philadelphia, PA (United States); Reiter, Sean B.; Kohn, Mark [DII - Diagnostic Imaging, Inc., Philadelphia, PA (United States)

    2007-03-15

    , as well as the constraining effect of the extensor retinaculum. These anatomical features determine the presence of characteristic MR imaging findings. (orig.)

  7. [Spatial distribution characteristics of urban potential population in Shenyang City based on QuickBird image and GIS].

    Science.gov (United States)

    Li, Jun-Ying; Hu, Yuan-Man; Chen, Wei; Liu, Miao; Hu, Jian-Bo; Zhong, Qiao-Lin; Lu, Ning

    2012-06-01

    Population is the most active factor affecting city development. To understand the distribution characteristics of urban population is of significance for making city policy decisions and for optimizing the layout of various urban infrastructures. In this paper, the information of the residential buildings in Shenyang urban area was extracted from the QuickBird remote sensing images, and the spatial distribution characteristics of the population within the Third-Ring Road of the City were analyzed, according to the social and economic statistics data. In 2010, the population density in different types of residential buildings within the Third-Ring Road of the City decreased in the order of high-storey block, mixed block, mixed garden, old multi-storey building, high-storey garden, multi-storey block, multi-storey garden, villa block, shanty, and villa garden. The vacancy rate of the buildings within the Third-Ring Road was more than 30%, meaning that the real estate market was seriously overstocked. Among the five Districts of Shenyang City, Shenhe District had the highest potential population density, while Tiexi District and Dadong District had a lower one. The gravity center of the City and its five Districts was also analyzed, which could provide basic information for locating commercial facilities and planning city infrastructure.

  8. Analyzing Thermal Characteristics of Urban Streets Using a Thermal Imaging Camera: A Case Study on Commercial Streets in Seoul, Korea

    Directory of Open Access Journals (Sweden)

    Sugie Lee

    2018-02-01

    Full Text Available Due to continuing city growth and global warming over the past decades, urban heat island (UHI effects, referring to the phenomena wherein the ambient air temperatures in cities are higher than those in rural areas, have become a serious threat to urban populations. Impervious surfaces, buildings with low-albedo materials, and a lack of vegetated areas are the major causes of poor urban thermal environments, particularly during the summer. Previous research has focused primarily on the thermal characteristics of individual building units. Few studies consider the impact of the street-scale thermal environments on the surface temperature, which affects pedestrian thermal comfort. The purpose of this study is to analyze the thermal characteristics of various physical elements on urban streets using thermal imaging cameras, and present policy implications for improving pedestrian thermal comfort. This study examines street-scale thermal environments of three major commercial streets: Garosu road, Serosu road, and Narosu road, in Seoul, Korea. This study conducted field measurements both during the day and the night in June 2017 in order to investigate changes in the urban surface temperatures across time. The results show that street trees are the most effective mitigation element for reducing surface temperatures. With regard to building use types, the highest surface temperatures are typically measured near restaurant buildings. Building façades that are dark-colored or partially covered with a metal contribute to high surface temperatures. Similarly, the temperatures of artificial turf or wooden decks on urban streets are also significantly high during the daytime. The thermal characteristics of various urban street elements should be considered to reduce the surface temperature and mitigate the urban heat island effect.

  9. Physical performance evaluation of GE DST PET-CT and evaluation of characteristics in dynamic image acquisition

    International Nuclear Information System (INIS)

    Lee, B. I.; Kim, J. Y.; Min, J. J.; Song, H. C.; Bom, H. S.; Kim, J. S.; Lee, J. S.

    2005-01-01

    As a new standard for performance measurement, NEMA NU2-2001 was presented recently. In this study, we investigated the spatial resolution, sensitivity, scatter fraction, and noise equivalent count ratio (NECR) in order to know the information of physical characteristics and system performance. Bismuth germinate crystals (6 X 6 array, 6.3mm X 6.3mm X 30mm) were used in discovery ST (energy window: 375-650 keV, coincidence window: 11.7 nsec). To measure the sensitivity, five aluminum sleeves (Data Spectrum Corp., Chapel Hill, NC., USA, thickness:1.25 mm) -NEMA sensitivity phantom- filled with F-18 solution were used. Spatial resolution was estimated using a point source (F-18, 0.1 mCi). Data were acquired while the count reaches at 100,000 and another experiment was performed at a distance of one-fourth the axial extent of the FOV. Scatter fraction and NECR was tested. Dynamic data were acquired for 7 half-lives. And true to background ratio was averaged at last three frames when the random rate was as small as ignorable for the calculation of scatter fraction. Sensitivity was 1.79 cps/kBq (2D) and 9.84 cps/kBq (3D) at the center and 1.78 cps/kBq (2D) and 9.60 cps/kBq (3D) at 10 cm off from the center. Spatial resolution at center was 6.15 mm (2D), 6.16 mm (3D) transverse direction and 5.77 mm (2D) and 5.93 mm (3D) at axial direction. At 10 cm radius, resolution of transverse radial was 7.19 mm (2D) and 7.16 mm (3D) and transverse tangential was 6.81 mm (2D) and 6.80mm (3D). Scatter fraction was 45.1% in 3D mode. Peak true rate and NECR were 325.1 kcps at 30.1 kBq/cc and 59.3 kcps at 13.7 kBq/cc. Dynamic image acquisition and gating image acquisition were acquired successfully. The physical characteristics of PET-CT were investigated. The sensitivity of installed system in 3D mode was better than the result of published study. We anticipate this overall evaluated results could be used for the quantification and optimized image acquisition for clinical research

  10. Magnetic resonance imaging characteristics and the prediction of outcome of vestibular schwannomas following Gamma Knife radiosurgery.

    Science.gov (United States)

    Wu, Chih-Chun; Guo, Wan-Yuo; Chung, Wen-Yuh; Wu, Hisu-Mei; Lin, Chung-Jung; Lee, Cheng-Chia; Liu, Kang-Du; Yang, Huai-Che

    2017-12-01

    OBJECTIVE Gamma Knife surgery (GKS) is a promising treatment modality for patients with vestibular schwannomas (VSs), but a small percentage of patients have persistent postradiosurgical tumor growth. The aim of this study was to determine the clinical and quantitative MRI features of VS as predictors of long-term tumor control after GKS. METHODS The authors performed a retrospective study of all patients with VS treated with GKS using the Leksell Gamma Knife Unit between 2005 and 2013 at their institution. A total of 187 patients who had a minimum of 24 months of clinical and radiological assessment after radiosurgery were included in this study. Those who underwent a craniotomy with tumor removal before and after GKS were excluded. Study patients comprised 85 (45.5%) males and 102 (54.5%) females, with a median age of 52.2 years (range 20.4-82.3 years). Tumor volumes, enhancing patterns, and apparent diffusion coefficient (ADC) values were measured by region of interest (ROI) analysis of the whole tumor by serial MRI before and after GKS. RESULTS The median follow-up period was 60.8 months (range 24-128.9 months), and the median treated tumor volume was 3.54 cm 3 (0.1-16.2 cm 3 ). At last follow-up, imaging studies indicated that 150 tumors (80.2%) showed decreased tumor volume, 20 (10.7%) had stabilized, and 17 (9.1%) continued to grow following radiosurgery. The postradiosurgical outcome was not significantly correlated with pretreatment volumes or postradiosurgical enhancing patterns. Tumors that showed regression within the initial 12 months following radiosurgery were more likely to have a larger volume reduction ratio at last follow-up than those that did not (volume reduction ratio 55% vs 23.6%, respectively; p < 0.001). Compared with solid VSs, cystic VSs were more likely to regress or stabilize in the initial postradiosurgical 6-12-month period and during extended follow-up. Cystic VSs exhibited a greater volume reduction ratio at last follow-up (cystic

  11. Is Personalized Communication Superior? Personalization and Consumers’ Characteristics

    NARCIS (Netherlands)

    Maslowska, E.; Smit, E.G.; van den Putte, B.

    2011-01-01

    Personalized communication has become a very popular marketing strategy, but the research on its effectiveness is still limited. This study examined the effectiveness of personalized digital newsletters in terms of increased attention, evaluation, attitude, and intention. Participants (N = 124) were

  12. Management of type II superior labrum anterior posterior lesions: a review of the literature

    Directory of Open Access Journals (Sweden)

    Xinning Li

    2010-02-01

    Full Text Available Superior labrum anterior and posterior lesions were first described in 1985 by Andrews et al. and later classified into four types by Synder et al. The most prevalent is type II which is fraying of the superior glenoid labrum with detachment of the biceps anchor. Superior labrum anterior posterior (SLAP lesions can also be associated with other shoulder pathology. Both MRI and MRA can be utilized in making the diagnosis with the coronal images being the most sensitive. The mechanism of injury can be either repetitive stress or acute trauma with the superior labrum most vulnerable to injury during the late cocking phase of throwing. A combination of the modified dynamic labral shear and O’Brien test can be used clinically in making the diagnosis of SLAP lesion. However, the most sensitive and specific test used to diagnosis specifically a type II SLAP lesion is the Biceps Load Test II. The management of type II SLAP lesions is controversial and dependent on patient characteristics. In the young high demanding overhead athlete, repair of the type II lesion is recommended to prevent glenohumeral instability. In middle-aged patients (age 25-45, repair of the type II SLAP lesion with concomitant treatment of other shoulder pathology resulted in better functional outcomes and patient satisfaction. Furthermore, patients who had a distinct traumatic event resulting in the type II SLAP tear did better functionally than patients who did not have the traumatic event when the lesion was repaired. In the older patient population (age over 45 years, minimum intervention (debridement, biceps tenodesis/tenotomy to the type II SLAP lesion results in excellent patient satisfaction and outcomes.

  13. Specific marker of feigned memory impairment: The activation of left superior frontal gyrus.

    Science.gov (United States)

    Chen, Zi-Xiang; Xue, Li; Liang, Chun-Yu; Wang, Li-Li; Mei, Wei; Zhang, Qiang; Zhao, Hu

    2015-11-01

    Faking memory impairment means normal people complain lots of memory problems without organic damage in forensic assessments. Using alternative forced-choice paradigm, containing digital or autobiographical information, previous neuroimaging studies have indicated that faking memory impairment could cause the activation in the prefrontal and parietal regions, and might involve a fronto-parietal-subcortical circuit. However, it is still unclear whether different memory types have influence on faking or not. Since different memory types, such as long-term memory (LTM) and short-term memory (STM), were found supported by different brain areas, we hypothesized that feigned STM or LTM impairment had distinct neural activation mapping. Besides that, some common neural correlates may act as the general characteristic of feigned memory impairment. To verify this hypothesis, the functional magnetic resonance imaging (fMRI) combined with an alternative word forced-choice paradigm were used in this study. A total of 10 right-handed participants, in this study, had to perform both STW and LTM tasks respectively under answering correctly, answering randomly and feigned memory impairment conditions. Our results indicated that the activation of the left superior frontal gyrus and the left medial frontal gyrus was associated with feigned LTM impairment, whereas the left superior frontal gyrus, the left precuneus and the right anterior cingulate cortex (ACC) were highly activated while feigning STM impairment. Furthermore, an overlapping was found in the left superior frontal gyrus, and it suggested that the activity of the left superior frontal gyrus might be acting as a specific marker of feigned memory impairment. Copyright © 2015. Published by Elsevier Ltd.

  14. Accommodation and convergence palsy caused by lesions in the bilateral rostral superior colliculus.

    Science.gov (United States)

    Ohtsuka, Kenji; Maeda, Sachie; Oguri, Naomi

    2002-03-01

    To report a patient who developed accommodation and convergence palsy caused by lesions in the bilateral rostral superior colliculus. Observational case report. A 30-year-old right-handed man experienced sudden onset of diplopia and blurred vision at near vision. The patient showed accommodation and convergence palsy. Magnetic resonance imaging revealed lesions located in the bilateral rostral superior colliculus. These findings suggest that the rostral superior colliculus is involved in the control of accommodation and vergence eye movements.

  15. Photon-counting hexagonal pixel array CdTe detector: Spatial resolution characteristics for image-guided interventional applications.

    Science.gov (United States)

    Vedantham, Srinivasan; Shrestha, Suman; Karellas, Andrew; Shi, Linxi; Gounis, Matthew J; Bellazzini, Ronaldo; Spandre, Gloria; Brez, Alessandro; Minuti, Massimo

    2016-05-01

    High-resolution, photon-counting, energy-resolved detector with fast-framing capability can facilitate simultaneous acquisition of precontrast and postcontrast images for subtraction angiography without pixel registration artifacts and can facilitate high-resolution real-time imaging during image-guided interventions. Hence, this study was conducted to determine the spatial resolution characteristics of a hexagonal pixel array photon-counting cadmium telluride (CdTe) detector. A 650 μm thick CdTe Schottky photon-counting detector capable of concurrently acquiring up to two energy-windowed images was operated in a single energy-window mode to include photons of 10 keV or higher. The detector had hexagonal pixels with apothem of 30 μm resulting in pixel pitch of 60 and 51.96 μm along the two orthogonal directions. The detector was characterized at IEC-RQA5 spectral conditions. Linear response of the detector was determined over the air kerma rate relevant to image-guided interventional procedures ranging from 1.3 nGy/frame to 91.4 μGy/frame. Presampled modulation transfer was determined using a tungsten edge test device. The edge-spread function and the finely sampled line spread function accounted for hexagonal sampling, from which the presampled modulation transfer function (MTF) was determined. Since detectors with hexagonal pixels require resampling to square pixels for distortion-free display, the optimal square pixel size was determined by minimizing the root-mean-squared-error of the aperture functions for the square and hexagonal pixels up to the Nyquist limit. At Nyquist frequencies of 8.33 and 9.62 cycles/mm along the apothem and orthogonal to the apothem directions, the modulation factors were 0.397 and 0.228, respectively. For the corresponding axis, the limiting resolution defined as 10% MTF occurred at 13.3 and 12 cycles/mm, respectively. Evaluation of the aperture functions yielded an optimal square pixel size of 54 μm. After resampling to 54

  16. Photon-counting hexagonal pixel array CdTe detector: Spatial resolution characteristics for image-guided interventional applications

    Energy Technology Data Exchange (ETDEWEB)

    Vedantham, Srinivasan; Shrestha, Suman; Karellas, Andrew, E-mail: andrew.karellas@umassmed.edu; Shi, Linxi; Gounis, Matthew J. [Department of Radiology, University of Massachusetts Medical School, Worcester, Massachusetts 01655 (United States); Bellazzini, Ronaldo; Spandre, Gloria; Brez, Alessandro; Minuti, Massimo [Istituto Nazionale di Fisica Nucleare (INFN), Pisa 56127, Italy and Pixirad Imaging Counters s.r.l., L. Pontecorvo 3, Pisa 56127 (Italy)

    2016-05-15

    Purpose: High-resolution, photon-counting, energy-resolved detector with fast-framing capability can facilitate simultaneous acquisition of precontrast and postcontrast images for subtraction angiography without pixel registration artifacts and can facilitate high-resolution real-time imaging during image-guided interventions. Hence, this study was conducted to determine the spatial resolution characteristics of a hexagonal pixel array photon-counting cadmium telluride (CdTe) detector. Methods: A 650 μm thick CdTe Schottky photon-counting detector capable of concurrently acquiring up to two energy-windowed images was operated in a single energy-window mode to include photons of 10 keV or higher. The detector had hexagonal pixels with apothem of 30 μm resulting in pixel pitch of 60 and 51.96 μm along the two orthogonal directions. The detector was characterized at IEC-RQA5 spectral conditions. Linear response of the detector was determined over the air kerma rate relevant to image-guided interventional procedures ranging from 1.3 nGy/frame to 91.4 μGy/frame. Presampled modulation transfer was determined using a tungsten edge test device. The edge-spread function and the finely sampled line spread function accounted for hexagonal sampling, from which the presampled modulation transfer function (MTF) was determined. Since detectors with hexagonal pixels require resampling to square pixels for distortion-free display, the optimal square pixel size was determined by minimizing the root-mean-squared-error of the aperture functions for the square and hexagonal pixels up to the Nyquist limit. Results: At Nyquist frequencies of 8.33 and 9.62 cycles/mm along the apothem and orthogonal to the apothem directions, the modulation factors were 0.397 and 0.228, respectively. For the corresponding axis, the limiting resolution defined as 10% MTF occurred at 13.3 and 12 cycles/mm, respectively. Evaluation of the aperture functions yielded an optimal square pixel size of 54

  17. Conversion of mammographic images to appear with the noise and sharpness characteristics of a different detector and x-ray system

    Energy Technology Data Exchange (ETDEWEB)

    Mackenzie, Alistair; Dance, David R.; Workman, Adam; Yip, Mary; Wells, Kevin; Young, Kenneth C. [National Coordinating Centre for the Physics of Mammography, Royal Surrey County Hospital, Guildford, GU2 7XX, United Kingdom and Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom); Northern Ireland Regional Medical Physics Service, Forster Green Hospital, Belfast, BT8 4HD (United Kingdom); Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom); Centre for Vision, Speech and Signal Processing, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH (United Kingdom); National Coordinating Centre for the Physics of Mammography, Royal Surrey County Hospital, Guildford, GU2 7XX, United Kingdom and Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom)

    2012-05-15

    Purpose: Undertaking observer studies to compare imaging technology using clinical radiological images is challenging due to patient variability. To achieve a significant result, a large number of patients would be required to compare cancer detection rates for different image detectors and systems. The aim of this work was to create a methodology where only one set of images is collected on one particular imaging system. These images are then converted to appear as if they had been acquired on a different detector and x-ray system. Therefore, the effect of a wide range of digital detectors on cancer detection or diagnosis can be examined without the need for multiple patient exposures. Methods: Three detectors and x-ray systems [Hologic Selenia (ASE), GE Essential (CSI), Carestream CR (CR)] were characterized in terms of signal transfer properties, noise power spectra (NPS), modulation transfer function, and grid properties. The contributions of the three noise sources (electronic, quantum, and structure noise) to the NPS were calculated by fitting a quadratic polynomial at each spatial frequency of the NPS against air kerma. A methodology was developed to degrade the images to have the characteristics of a different (target) imaging system. The simulated images were created by first linearizing the original images such that the pixel values were equivalent to the air kerma incident at the detector. The linearized image was then blurred to match the sharpness characteristics of the target detector. Noise was then added to the blurred image to correct for differences between the detectors and any required change in dose. The electronic, quantum, and structure noise were added appropriate to the air kerma selected for the simulated image and thus ensuring that the noise in the simulated image had the same magnitude and correlation as the target image. A correction was also made for differences in primary grid transmission, scatter, and veiling glare. The method was

  18. Temporal Bone Fracture Causing Superior Semicircular Canal Dehiscence

    Directory of Open Access Journals (Sweden)

    Kevin A. Peng

    2014-01-01

    Full Text Available Importance. Superior semicircular canal dehiscence (SCD is a third window lesion of the inner ear causing symptoms of vertigo, autophony, tinnitus, and hearing loss. A “two-hit” hypothesis has traditionally been proposed, whereby thinly developed bone overlying the superior canal is disrupted by a sudden change in intracranial pressure. Although the symptoms of SCD may be precipitated by head injury, no previous reports have described a temporal bone fracture directly causing SCD. Observations. Two patients sustained temporal bone fractures after closed head trauma, and developed unilateral otologic symptoms consistent with SCD. In each instance, computed tomography imaging revealed fractures extending through the bony roof of the superior semicircular canal. Conclusions and Relevance. Temporal bone fractures, which are largely treated nonoperatively, have not previously been reported to cause SCD. As it is a potentially treatable entity, SCD resulting from temporal bone fracture must be recognized as a possibility and diagnosed promptly if present.

  19. Predictive modeling of outcomes following definitive chemoradiotherapy for oropharyngeal cancer based on FDG-PET image characteristics

    Science.gov (United States)

    Folkert, Michael R.; Setton, Jeremy; Apte, Aditya P.; Grkovski, Milan; Young, Robert J.; Schöder, Heiko; Thorstad, Wade L.; Lee, Nancy Y.; Deasy, Joseph O.; Oh, Jung Hun

    2017-07-01

    In this study, we investigate the use of imaging feature-based outcomes research (‘radiomics’) combined with machine learning techniques to develop robust predictive models for the risk of all-cause mortality (ACM), local failure (LF), and distant metastasis (DM) following definitive chemoradiation therapy (CRT). One hundred seventy four patients with stage III-IV oropharyngeal cancer (OC) treated at our institution with CRT with retrievable pre- and post-treatment 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) scans were identified. From pre-treatment PET scans, 24 representative imaging features of FDG-avid disease regions were extracted. Using machine learning-based feature selection methods, multiparameter logistic regression models were built incorporating clinical factors and imaging features. All model building methods were tested by cross validation to avoid overfitting, and final outcome models were validated on an independent dataset from a collaborating institution. Multiparameter models were statistically significant on 5 fold cross validation with the area under the receiver operating characteristic curve (AUC)  =  0.65 (p  =  0.004), 0.73 (p  =  0.026), and 0.66 (p  =  0.015) for ACM, LF, and DM, respectively. The model for LF retained significance on the independent validation cohort with AUC  =  0.68 (p  =  0.029) whereas the models for ACM and DM did not reach statistical significance, but resulted in comparable predictive power to the 5 fold cross validation with AUC  =  0.60 (p  =  0.092) and 0.65 (p  =  0.062), respectively. In the largest study of its kind to date, predictive features including increasing metabolic tumor volume, increasing image heterogeneity, and increasing tumor surface irregularity significantly correlated to mortality, LF, and DM on 5 fold cross validation in a relatively uniform single-institution cohort. The LF model also retained

  20. Superior glenoid inclination and rotator cuff tears.

    Science.gov (United States)

    Chalmers, Peter N; Beck, Lindsay; Granger, Erin; Henninger, Heath; Tashjian, Robert Z

    2018-03-23

    The objectives of this study were to determine whether glenoid inclination (1) could be measured accurately on magnetic resonance imaging (MRI) using computed tomography (CT) as a gold standard, (2) could be measured reliably on MRI, and (3) whether it differed between patients with rotator cuff tears and age-matched controls without evidence of rotator cuff tears or glenohumeral osteoarthritis. In this comparative retrospective radiographic study, we measured glenoid inclination on T1 coronal MRI corrected into the plane of the scapula. We determined accuracy by comparison with CT and inter-rater reliability. We compared glenoid inclination between patients with full-thickness rotator cuff tears and patients aged >50 years without evidence of a rotator cuff tear or glenohumeral arthritis. An a priori power analysis determined adequate power to detect a 2° difference in glenoid inclination. (1) In a validation cohort of 37 patients with MRI and CT, the intraclass correlation coefficient was 0.877, with a mean difference of 0° (95% confidence interval, -1° to 1°). (2) For MRI inclination, the inter-rater intraclass correlation coefficient was 0.911. (3) Superior glenoid inclination was 2° higher (range, 1°-4°, P rotator cuff tear group of 192 patients than in the control cohort of 107 patients. Glenoid inclination can be accurately and reliably measured on MRI. Although superior glenoid inclination is statistically greater in those with rotator cuff tears than in patients of similar age without rotator cuff tears or glenohumeral arthritis, the difference is likely below clinical significance. Copyright © 2018 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  1. Cine computed tomography for diagnosis of superior vena cava obstruction following the mustard operation

    International Nuclear Information System (INIS)

    Matherne, G.P.; Atkins, D.L.; Frey, E.E.; Smith, W.L.

    1987-01-01

    Superior vena caval obstruction is a well described complication following Mustard's repair for transposition of the great arteries. We report a case of a 6-year-old child with superior vena cava obstruction correctly diagnosed by Cine-CT. The advantages of imaging with Cine-CT for this complication are discussed. (orig.)

  2. Escuela Superior de Palos Verdes

    Directory of Open Access Journals (Sweden)

    Neutra, Richard J.

    1965-02-01

    Full Text Available Before initiating the building operations for the «Palos Verdes» School, the site was divided into two large horizontal surfaces, at different levels. The lower one served to accommodate the playing fields, a car park, the physical training building, and shop and ancillary buildings. On the higher of these two surfaces, and to the West of the access road, there is a car park and also the building and plot of ground devoted to agricultural technology, as well as the literary studies and general purpose buildings. As a complement to these, there is a series of blocks, arranged in parallel rows, which house the administrative offices, the art school, the craft's school, the general classrooms, and those devoted to higher education. The fascinating aspect of this school is the outstanding penetration of the architect's mind into the essential function of the project. Its most evident merit is the sense of comradeship and harmony that permeates the whole architectural manifold.Antes de construir el complejo escolar «Palos Verdes» se comenzó por crear, en el terreno, dos grandes mesetas a niveles diferentes. Sobre el inferior se organizaron: los campos de juegos, de deportes, un aparcamiento, el edificio para educación física y los destinados a tiendas y servicios. Sobre la meseta superior, al oeste de la vía de acceso, se dispuso un aparcamiento y el edificio y campo para adiestramiento agrícola; al este, otro aparcamiento, el edificio dedicado a materias literarias, y el destinado a usos múltiples. Completan las instalaciones de la escuela una serie de bloques paralelos: la administración, la escuela de arte, las clases de trabajos manuales, las aulas de enseñanzas generales, y las de los cursos superiores. Lo fascinante de este complejo escolar es la perfecta y magistral compenetración del arquitecto con el tema proyectado, y su mayor mérito, la sensación de cordialidad y armonía con el ambiente.

  3. Neurocognitive decrements are present in intellectually superior schizophrenia

    Directory of Open Access Journals (Sweden)

    Anja eVaskinn

    2014-05-01

    Full Text Available Data suggests that individuals with schizophrenia (SZ and superior intelligence can present without specific neurocognitive deficits. However, neurocognitive decrements, defined as worse cognition than expected, have been reported in practically all schizophrenia cases. This study investigated if neurocognitive decrements are present in intellectually superior SZ by comparing the neuropsychological profile of SZ cases with IQ-matched healthy controls (HC across intellectual level. Participants with SZ and HCs were stratified into three IQ-groups; intellectually low (IQ 80-95; SZ n = 65 & HC n = 13, intellectually normal (IQ = 100-115; SZ n = 111 & HC n = 115 and intellectually superior (IQ > 120; SZ n = 20 & HC n = 50. A repeated measures multivariate analysis of co-variance compared performance on eight selected neuropsychological tests across IQ-strata and diagnostic group. Differences in clinical characteristics and social functioning in SZ across IQ-strata were investigated with multivariate and univariate analyses of variance. Intellectually superior SZ participants scored within normal limits, but had neurocognitive decrements compared to superior HCs. Decrements were of the same magnitude as in the low and normal IQ-strata. Levels of functional impairments and clinical characteristics in participants with SZ did not differ significantly across IQ-strata. Results indicate that neurocognitive decrements are present in intellectually superior SZ to the same extent as in intellectually low and intellectually normal SZ, supporting the notion that SZ is a neurocognitive disorder. Similar levels of social functional deficits and clinical symptoms suggest similar disease processes in SZ across intellectual level.

  4. RESEARCH OF NIGHT LIGHT EFFECTS ON COLORIMETRIC CHARACTERISTICS OF IMAGE PERCEIVED BY THE PILOT IN AN AIRCRAFT COCKPIT

    Directory of Open Access Journals (Sweden)

    I. O. Zharinov

    2015-09-01

    Full Text Available Subject of Research. The influence of radiation spectra from the source of artificial night light on colorimetric characteristics of image perceived by the pilot in the aircraft cockpit has been studied. The image is displayed on the LCD screen of multifunctional color indication equipment unit. Night illumination of the cockpit is performed with the use of artificial lamps of red, green, blue and, rarely, white light. Method. Any given color to be displayed on the screen is perceived by an observer differently with presence and absence of external illumination. When external light of white color is used, perceived color depends upon color temperature of the light source; if illumination source has any arbitrary spectral characteristics, then perceivable color depends upon whole spectral content of the used source. The color, perceived by an observer, is formed as the mixture of the color displayed on the screen (image element color with the color presented by diffuse reflection of external illumination source from the surface of the screen. The brightness of both colors is added. Mathematical expressions, that define calculation rule for chromaticity coordinates of color perceived by an observer, are based on the Grassmann’s law of additive color mixing. Quantitative analysis of the effect, caused by radiation spectra from an external source of artificial light on color gamut area, corresponding to image, perceived by an observer, has been performed through simulation in MathCad 15.0. Main Results. It was shown, that the color palette of on-board indication equipment, obtained on automated working place for any preset source of external illumination of fluorescent spectrum, corresponding to white light, is not usable correctly in the aircraft night flight mode. An observer loses ability to perceive properly saturated primary colors of red and blue in the case of green-blue light source of external illumination; and the same issue occurs with

  5. A comparison of the imaging characteristics of the new Kodak Hyper Speed G film with the current T-MAT G/RA film and the CR 9000 system.

    Science.gov (United States)

    Monnin, P; Gutierrez, D; Bulling, S; Lepori, D; Verdun, F R

    2005-10-07

    Three standard radiation qualities (RQA 3, RQA 5 and RQA 9) and two screens, Kodak Lanex Regular and Insight Skeletal, were used to compare the imaging performance and dose requirements of the new Kodak Hyper Speed G and the current Kodak T-MAT G/RA medical x-ray films. The noise equivalent quanta (NEQ) and detective quantum efficiencies (DQE) of the four screen-film combinations were measured at three gross optical densities and compared with the characteristics for the Kodak CR 9000 system with GP (general purpose) and HR (high resolution) phosphor plates. The new Hyper Speed G film has double the intrinsic sensitivity of the T-MAT G/RA film and a higher contrast in the high optical density range for comparable exposure latitude. By providing both high sensitivity and high spatial resolution, the new film significantly improves the compromise between dose and image quality. As expected, the new film has a higher noise level and a lower signal-to-noise ratio than the standard film, although in the high frequency range this is compensated for by a better resolution, giving better DQE results--especially at high optical density. Both screen-film systems outperform the phosphor plates in terms of MTF and DQE for standard imaging conditions (Regular screen at RQA 5 and RQA 9 beam qualities). At low energy (RQA 3), the CR system has a comparable low-frequency DQE to screen-film systems when used with a fine screen at low and middle optical densities, and a superior low-frequency DQE at high optical density.

  6. A comparison of the imaging characteristics of the new Kodak Hyper Speed G film with the current T-MAT G/RA film and the CR 9000 system

    Energy Technology Data Exchange (ETDEWEB)

    Monnin, P [Institut universitaire de Radiophysique Appliquee (IRA), CH-1007 Lausanne (Switzerland); Gutierrez, D [Institut universitaire de Radiophysique Appliquee (IRA), CH-1007 Lausanne (Switzerland); Bulling, S [Institut universitaire de Radiophysique Appliquee (IRA), CH-1007 Lausanne (Switzerland); Lepori, D [Department of Radiology, University Hospital Center (CHUV), CH-1011 Lausanne (Switzerland); Verdun, F R [Institut universitaire de Radiophysique Appliquee (IRA), CH-1007 Lausanne (Switzerland)

    2005-10-07

    Three standard radiation qualities (RQA 3, RQA 5 and RQA 9) and two screens, Kodak Lanex Regular and Insight Skeletal, were used to compare the imaging performance and dose requirements of the new Kodak Hyper Speed G and the current Kodak T-MAT G/RA medical x-ray films. The noise equivalent quanta (NEQ) and detective quantum efficiencies (DQE) of the four screen-film combinations were measured at three gross optical densities and compared with the characteristics for the Kodak CR 9000 system with GP (general purpose) and HR (high resolution) phosphor plates. The new Hyper Speed G film has double the intrinsic sensitivity of the T-MAT G/RA film and a higher contrast in the high optical density range for comparable exposure latitude. By providing both high sensitivity and high spatial resolution, the new film significantly improves the compromise between dose and image quality. As expected, the new film has a higher noise level and a lower signal-to-noise ratio than the standard film, although in the high frequency range this is compensated for by a better resolution, giving better DQE results-especially at high optical density. Both screen-film systems outperform the phosphor plates in terms of MTF and DQE for standard imaging conditions (Regular screen at RQA 5 and RQA 9 beam qualities). At low energy (RQA 3), the CR system has a comparable low-frequency DQE to screen-film systems when used with a fine screen at low and middle optical densities, and a superior low-frequency DQE at high optical density.

  7. Clinical characteristics of patient selection and imaging predictors of outcome in solid tumors treated with checkpoint-inhibitors

    International Nuclear Information System (INIS)

    Rossi, Sabrina; Toschi, Luca; Castello, Angelo; Grizzi, Fabio; Mansi, Luigi; Lopci, Egesta

    2017-01-01

    The rapidly evolving knowledge on tumor immunology and the continuous implementation of immunotherapy in cancer have recently led to the FDA and EMA approval of several checkpoint inhibitors as immunotherapic agents in clinical practice. Anti-CTLA-4, anti-PD-1, and anti-PDL-1 antibodies are becoming standard of care in advanced melanoma, as well as in relapsed or metastatic lung and kidney cancer, demonstrating higher and longer response compared to standard chemotherapy. These encouraging results have fostered the evaluation of these antibodies either alone or in combination with other therapies in several dozen clinical trials for the treatment of multiple tumor types. However, not all patients respond to immune checkpoint inhibitors, hence, specific biomarkers are necessary to guide and monitor therapy. The utility of PD-L1 expression as a biomarker has varied in different clinical trials, but, to date, no consensus has been reached on whether PD-L1 expression is an ideal marker for response and patient selection; approximately 20-25% of patients will respond to immunotherapy with checkpoint inhibitors despite a negative PD-L1 staining. On the other hand, major issues concern the evaluation of objective response in patients treated with immunotherapy. Pure morphological criteria as commonly used in solid tumors (i.e. RECIST) are not sufficient because change in size is not an early and reliable marker of tumor response to biological therapies. Thus, the scientific community has required a continuous adaptation of immune-related response criteria (irRC) to overcome the problem. In this context, metabolic information and antibody-based imaging with positron emission tomography (PET) have been investigated, providing a powerful approach for an optimal stratification of patients at staging and during the evaluation of the response to therapy. In the present review we provide an overview on the clinical characteristics of patient selection when using imaging

  8. Clinical characteristics of patient selection and imaging predictors of outcome in solid tumors treated with checkpoint-inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, Sabrina; Toschi, Luca [Humanitas Clinical and Research Hospital, Medical Oncology, Rozzano (Italy); Castello, Angelo [Humanitas Clinical and Research Hospital, Nuclear Medicine, Rozzano (Italy); Grizzi, Fabio [Humanitas Clinical and Research Hospital, Immunology and Inflammation, Rozzano (Italy); Mansi, Luigi [Seconda Universita di Napoli, Nuclear Medicine, Naples (Italy); Lopci, Egesta [Humanitas Clinical and Research Hospital, Nuclear Medicine, Rozzano (Italy); Humanitas Cancer Center, Humanitas Clinical and Research Hospital, Nuclear Medicine, Rozzano, MI (Italy)

    2017-12-15

    The rapidly evolving knowledge on tumor immunology and the continuous implementation of immunotherapy in cancer have recently led to the FDA and EMA approval of several checkpoint inhibitors as immunotherapic agents in clinical practice. Anti-CTLA-4, anti-PD-1, and anti-PDL-1 antibodies are becoming standard of care in advanced melanoma, as well as in relapsed or metastatic lung and kidney cancer, demonstrating higher and longer response compared to standard chemotherapy. These encouraging results have fostered the evaluation of these antibodies either alone or in combination with other therapies in several dozen clinical trials for the treatment of multiple tumor types. However, not all patients respond to immune checkpoint inhibitors, hence, specific biomarkers are necessary to guide and monitor therapy. The utility of PD-L1 expression as a biomarker has varied in different clinical trials, but, to date, no consensus has been reached on whether PD-L1 expression is an ideal marker for response and patient selection; approximately 20-25% of patients will respond to immunotherapy with checkpoint inhibitors despite a negative PD-L1 staining. On the other hand, major issues concern the evaluation of objective response in patients treated with immunotherapy. Pure morphological criteria as commonly used in solid tumors (i.e. RECIST) are not sufficient because change in size is not an early and reliable marker of tumor response to biological therapies. Thus, the scientific community has required a continuous adaptation of immune-related response criteria (irRC) to overcome the problem. In this context, metabolic information and antibody-based imaging with positron emission tomography (PET) have been investigated, providing a powerful approach for an optimal stratification of patients at staging and during the evaluation of the response to therapy. In the present review we provide an overview on the clinical characteristics of patient selection when using imaging

  9. Nasopharyngeal carcinoma: comparison of diffusion and perfusion characteristics between different tumour stages using intravoxel incoherent motion MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Vincent; Li, Xiao; Huang, Bingsheng; Khong, Pek Lan [University of Hong Kong, Queen Mary Hospital, Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, Hong Kong (China); Lee, Victor Ho Fun; Lam, Ka On [University of Hong Kong, Queen Mary Hospital, Department of Clinical Oncology, Li Ka Shing Faculty of Medicine, Hong Kong (China); Fong, Daniel Yee Tak [University of Hong Kong, School of Nursing, Li Ka Shing Faculty of Medicine, Hong Kong (China); Chan, Queenie [Philips Healthcare, Hong Kong, New Territories (China)

    2014-01-15

    To explore intravoxel incoherent motion (IVIM) characteristics of nasopharyngeal carcinoma (NPC) and relationships with different tumour stages. We prospectively recruited 80 patients with newly diagnosed undifferentiated NPC. Diffusion-weighted MR imaging was performed and IVIM parameters (D, pure diffusion; f, perfusion fraction; D*, pseudodiffusion coefficient) were calculated. Patients were stratified into low and high tumour stage groups based on American Joint Committee on Cancer (AJCC) and TNM staging for determination of the predictive powers of IVIM parameters using t test, multiple logistic regression and ROC curve analyses. D, f and D* were all statistically significantly lower in high-stage groups in AJCC, T and N staging. D, f and D* were all independent predictors of AJCC staging, f and D* were independent predictors of T staging, and D was an independent predictor of N staging. D was most powerful for AJCC and N staging, whereas f was most powerful for T staging. Optimal cut-off values (area under the curve, sensitivity, specificity, positive likelihood ratio, negative likelihood ratio) were as follows: AJCC stage, D = 0.782 x 10{sup -3} mm{sup 2}/s (0.915, 93.3 %, 76.2 %, 3.92, 0.09); T staging, f = 0.133 (0.905, 80.5 %, 92.5 %, 10.73, 0.21); N staging, D = 0.761 x 10{sup -3} mm{sup 2}/s (0.848, 87.5 %, 66.7 %, 2.62, 0.19). Multivariate analysis showed no diagnostic improvement. Nasopharyngeal carcinoma has distinctive intravoxel incoherent motion characteristics parameters in different tumour staging, potentially helping pretreatment staging. (orig.)

  10. Effects of Injection Timing on Fluid Flow Characteristics of Partially Premixed Combustion Based on High-Speed Particle Image Velocimetry

    KAUST Repository

    Izadi Najafabadi, Mohammad

    2017-03-28

    Partially Premixed Combustion (PPC) is a promising combustion concept ,based on judicious tuning of the charge stratification, to meet the increasing demands of emission legislation and to improve fuel efficiency. Longer ignition delays of PPC in comparison with conventional diesel combustion provide better fuel/air mixture which decreases soot and NO emissions. Moreover, a proper injection timing and strategy for PPC can improve the combustion stability as a result of a higher level of fuel stratification in comparison with the Homogeneous Charge Compression Ignition (HCCI) concept. Injection timing is the major parameter with which to affect the level of fuel and combustion stratification and to control the combustion phasing and the heat release behavior. The scope of the present study is to investigate the fluid flow characteristics of PPC at different injection timings. To this end, high-speed Particle Image Velocimetry (PIV) is implemented in a light-duty optical engine to measure fluid flow characteristics, including the flow fields, mean velocity and cycle-resolved turbulence, inside the piston bowl as well as the squish region with a temporal resolution of 1 crank angle degree at 800 rpm. Two injectors, having 5 and 7 holes, were compared to see their effects on fluid flow and heat release behavior for different injection timings. Reactive and non-reactive measurements were performed to distinguish injection-driven and combustion-driven turbulence. Formation of vortices and higher turbulence levels enhance the air/fuel interaction, changing the level of fuel stratification and combustion duration. Results demonstrate clearly how turbulence level correlates with heat release behavior, and provide a quantitative dataset for validation of numerical simulations.

  11. Imaging Characteristics and Prevalence of Pancreatic Carcinoma in Kosovo During 2011-2015 - Diagnostic Method as Choice

    Science.gov (United States)

    Dedushi, Kreshnike; Kabashi, Serbeze; Mucaj, Sefedin; Hasbahta, Gazmed; Ramadani, Naser; Hoxhaj, Astrit

    2016-01-01

    Introduction: Pancreatic cancer is the 10thmost common malignancy and the 4thlargest cancer killer in adults. Aim: The purpose of this paper is to evaluate the number of cases presented with pancreatic carcinoma during the years 2011-2015, our experience of the imaging characteristics of pancreatic carcinoma. We evaluated prevalence of the pancreatic cancers, distant metastases and other local infiltration signs among the total cases of the pancreatic cancers diagnosed in the University Clinical Center of Kosovo, with the aim to compare these research findings to similar studies made in the developed countries. This is a retrospective research study done during the period of 2011-2015. Materials and Methodology: This retrospective research study includes 362 patients recently diagnosed with pancreatic cancer, examined in the period of 2011-2015 at the University Clinical Center of Kosovo. The imaging diagnostics are performed with MSCT Sensation 64 Siemens, MSCT Emotion 6 Siemens, and 1.5T MRI Symphony Siemens, biopsy guide with MSCT Sensation 64 Siemens in the Radiologic Clinic of UCCK; while the histopathology diagnostics has been performed in Clinic of Pathology at UCCK and prevalence is taken from the number of cases Reported at the Institute of Oncology Institute of Statistics and NIPH (National Institute of Public Health of Kosovo). Results: Out of a total of the 362 patients diagnosed with pancreas cancer, results is female 39.5% (n=143) and male 61.5% (n=219), report M: F (1: 1.6), 286 cases resulted in head and neck 79 % (n=286), 76 cases resulted in body and tail cancers (21%), distant metastases in first imaging modality were found in(n=155) patients 43 %, local infiltration was found in patients: gastric infiltration 15 % (n=54), duodenal and papilla infiltration 26% (n=94), local infiltration spleen 16% (n=57), local infiltration mesentery 43 % (n= 155), dilated biliary tree 34 % (n=123), regional lymph node infiltration 83 % (n= 300). Out of a total

  12. In situ diagnostic of water distribution in thickness direction of MEA by neutron imaging. Focused on characteristics of water distribution in gas diffusion layer

    International Nuclear Information System (INIS)

    Tasaki, Yutaka; Ichikawa, Yasushi; Kobo, Norio; Shinohara, Kazuhiko; Boillat, Pierre; Kramer, Denis; Scherer, Gunther G.; Lehmann, Eberhard H.

    2008-01-01

    The mass transfer characteristics of gas diffusion layer (GDL) are closely related to cell performance in PEFC. In this study, In situ diagnostic of water distribution in thickness direction of MEA by Neutron Imaging has been carried out for three MEAs with different GDLs on cathode side as well as I-V characteristics. It was confirmed that this method is useful for analyzing water distribution in thickness direction of MEA. The relationship between I-V characteristics and liquid water distribution has been studied. (author)

  13. Sobredentadura total superior implantosoportada Superior total overdenture on implants

    Directory of Open Access Journals (Sweden)

    Luis Orlando Rodríguez García

    2010-06-01

    Full Text Available Se presenta un caso de un paciente desdentado total superior, rehabilitado en la consulta de implantología de la Clínica "Pedro Ortiz" del municipio Habana del Este en Ciudad de La Habana, Cuba, en el año 2009, mediante prótesis sobre implantes osteointegrados, técnica que se ha incorporado a la práctica estomatológica en Cuba como alternativa al tratamiento convencional en los pacientes desdentados totales. Se siguió un protocolo que comprendió una fase quirúrgica, procedimiento con o sin realización de colgajo y carga precoz o inmediata. Se presenta un paciente masculino de 56 años de edad, que acudió a la consulta multidisciplinaria, preocupado, porque se le habían elaborado tres prótesis en los últimos dos años y ninguna reunía los requisitos de retención que él necesitaba para sentirse seguro y cómodo con las mismas. El resultado final fue la satisfacción total del paciente, con el mejoramiento de la calidad estética y funcional.This is the case of a total maxilla edentulous patient seen in consultation of the "Pedro Ortíz" Clinic Implant of Habana del Este municipality in 2009 and con rehabilitation by prosthesis over osteointegration implants added to stomatology practice in Cuba as an alternative to conventional treatment in patients totally edentulous. We follow a protocol including a surgery or surgical phase, technique without or with flap creation and early or immediate load. This is a male patient aged 56 came to our multidisciplinary consultation worried because he had three prostheses in last two years and any fulfilled the requirements of retention to feel safe and comfortable with prostheses. The final result was the total satisfaction of rehabilitated patient improving its aesthetic and functional quality.

  14. Tears at the rotator cuff footprint: Prevalence and imaging characteristics in 305 MR arthrograms of the shoulder

    International Nuclear Information System (INIS)

    Schaeffeler, Christoph; Mueller, Dirk; Rummeny, Ernst J.; Woertler, Klaus; Kirchhoff, Chlodwig; Wolf, Petra

    2011-01-01

    To evaluate the prevalence, imaging characteristics and anatomical distribution of tears at the rotator cuff (RC) footprint with MR arthrography (MR-A) of the shoulder. MR arthrograms obtained in 305 patients were retrospectively reviewed. Partial articular-sided supraspinatus tendon avulsions (PASTA), concealed interstitial delaminations (CID), reverse PASTA lesions and full-thickness tears (FT) at the humeral tendon insertion were depicted. Anatomical locations were determined and depths of tears were classified. 112/305 patients showed RC tears, including 63 patients with 68 footprint tears. 34 PASTA lesions were detected with 20/34 involving the anterior supraspinatus (SSP) tendon and 17/34 PASTA lesions were grade I lesions. Most CID lesions (14/23) occurred at the posterior SSP and 20/23 were classified as grade I or II. 9 FT and 2 reverse PASTA lesions were found. Statistical analysis revealed no difference in anatomical location (p = 0.903) and no correlation with overhead sports activity (p = 0.300) or history of trauma (p=0.928). There were significantly more PASTA lesions in patients <40 years of age (p = 0.029). Most RC tears detected with MR-A involve the SSP footprint and are articular-sided with predominance in younger patients, but concealed lesions are not as uncommon as previously thought. (orig.)

  15. Tears at the rotator cuff footprint: Prevalence and imaging characteristics in 305 MR arthrograms of the shoulder

    Energy Technology Data Exchange (ETDEWEB)

    Schaeffeler, Christoph; Mueller, Dirk; Rummeny, Ernst J.; Woertler, Klaus [Technische Universitaet Muenchen, Department of Radiology, Munich (Germany); Kirchhoff, Chlodwig [Technische Universitaet Muenchen, Department of Orthopedics and Traumatology, Munich (Germany); Wolf, Petra [Technische Universitaet Muenchen, Institute of Medical Statistics and Epidemiology, Munich (Germany)

    2011-07-15

    To evaluate the prevalence, imaging characteristics and anatomical distribution of tears at the rotator cuff (RC) footprint with MR arthrography (MR-A) of the shoulder. MR arthrograms obtained in 305 patients were retrospectively reviewed. Partial articular-sided supraspinatus tendon avulsions (PASTA), concealed interstitial delaminations (CID), reverse PASTA lesions and full-thickness tears (FT) at the humeral tendon insertion were depicted. Anatomical locations were determined and depths of tears were classified. 112/305 patients showed RC tears, including 63 patients with 68 footprint tears. 34 PASTA lesions were detected with 20/34 involving the anterior supraspinatus (SSP) tendon and 17/34 PASTA lesions were grade I lesions. Most CID lesions (14/23) occurred at the posterior SSP and 20/23 were classified as grade I or II. 9 FT and 2 reverse PASTA lesions were found. Statistical analysis revealed no difference in anatomical location (p = 0.903) and no correlation with overhead sports activity (p = 0.300) or history of trauma (p=0.928). There were significantly more PASTA lesions in patients <40 years of age (p = 0.029). Most RC tears detected with MR-A involve the SSP footprint and are articular-sided with predominance in younger patients, but concealed lesions are not as uncommon as previously thought. (orig.)

  16. Experimental investigation of ash deposits characteristics of co-combustion of coal and rice hull using a digital image technique

    International Nuclear Information System (INIS)

    Qiu, Kunzan; Zhang, Hailong; Zhou, Hao; Zhou, Bin; Li, Letian; Cen, Kefa

    2014-01-01

    This paper investigated the ash deposit characteristics during the co-firing Da Tong (DA) coal with different proportions of rice hull (0%, 5%, 10%, and 20%, based on weight) in a pilot-scale furnace. The growth of ash deposit with a four-stage mode was presented. The stable thickness values of DA coal, 5% rice hull, 10% rice hull, and 20% rice hull were 0.5, 1.4, 2.9, 5.7 cm, with stable heat flux values of 230, 200, 175, and 125 kW/m 2 , respectively. According to the results of scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX), the amount of Si in the deposits increased with the increasing proportion of rice hull rich in SiO 2 . The X-ray diffraction (XRD) analysis results indicated that most elements except Si were in the amorphous state because of the formation of eutectics. The stable thicknesses of deposits increased exponentially with the proportion of rice hull. The deposit was loose, easy removable but it reduced the heat transfer significantly. Consequently, sootblowing timely was necessary when co-firing DA coal with rice hull. - Highlights: • Digital image technique was used to monitor deposits growth process. • A type of four stages mode of ash deposit growth was presented. • The heat flux of ash deposits fit a three-stage mode. • The addition of rice hull increased the porosity of deposits

  17. ROC [Receiver Operating Characteristics] study of maximum likelihood estimator human brain image reconstructions in PET [Positron Emission Tomography] clinical practice

    International Nuclear Information System (INIS)

    Llacer, J.; Veklerov, E.; Nolan, D.; Grafton, S.T.; Mazziotta, J.C.; Hawkins, R.A.; Hoh, C.K.; Hoffman, E.J.

    1990-10-01

    This paper will report on the progress to date in carrying out Receiver Operating Characteristics (ROC) studies comparing Maximum Likelihood Estimator (MLE) and Filtered Backprojection (FBP) reconstructions of normal and abnormal human brain PET data in a clinical setting. A previous statistical study of reconstructions of the Hoffman brain phantom with real data indicated that the pixel-to-pixel standard deviation in feasible MLE images is approximately proportional to the square root of the number of counts in a region, as opposed to a standard deviation which is high and largely independent of the number of counts in FBP. A preliminary ROC study carried out with 10 non-medical observers performing a relatively simple detectability task indicates that, for the majority of observers, lower standard deviation translates itself into a statistically significant detectability advantage in MLE reconstructions. The initial results of ongoing tests with four experienced neurologists/nuclear medicine physicians are presented. Normal cases of 18 F -- fluorodeoxyglucose (FDG) cerebral metabolism studies and abnormal cases in which a variety of lesions have been introduced into normal data sets have been evaluated. We report on the results of reading the reconstructions of 90 data sets, each corresponding to a single brain slice. It has become apparent that the design of the study based on reading single brain slices is too insensitive and we propose a variation based on reading three consecutive slices at a time, rating only the center slice. 9 refs., 2 figs., 1 tab

  18. Possible origin of superior corrosion resistance for electrodeposited nanocrystalline Ni

    International Nuclear Information System (INIS)

    Roy, I.; Yang, H.W.; Dinh, L.; Lund, I.; Earthman, J.C.; Mohamed, F.A.

    2008-01-01

    We present here for the first time observations that grain boundaries in electrodeposited (ED) nanocrystalline (nc) Ni are predominantly of Σ3 character. The results presented are based on orientation imaging microscopy (OIM) performed to produce electron backscatter diffraction (EBSD) maps. This large volume fraction of coherent low sigma coincidence site lattice (CSL) boundaries appears to be consistent with the superior corrosion resistance of ED nc-Ni in comparison with its coarse-grained counterpart

  19. Superior vesical fissure concealed by giant omphalocele: A case report

    OpenAIRE

    Hayek, Danial; Massanyi, Eric; Mancuso, Melissa; Krepkovich, Katherine; Garrison, Aaron

    2016-01-01

    Omphalocele is an abdominal wall defect characterized by exteriorization of abdominal viscera that is covered by a membrane. Omphalocele has a well-known association with chromosome abnormalities. Here we present a case of a superior vesical fissure (SVF) initially disguised as a giant omphalocele in a newborn with trisomy 18. We also show unique prenatal imaging and discuss the importance and limitations of prenatal genetic testing.

  20. Superior vesical fissure concealed by giant omphalocele: A case report

    Directory of Open Access Journals (Sweden)

    Danial Hayek

    2016-11-01

    Full Text Available Omphalocele is an abdominal wall defect characterized by exteriorization of abdominal viscera that is covered by a membrane. Omphalocele has a well-known association with chromosome abnormalities. Here we present a case of a superior vesical fissure (SVF initially disguised as a giant omphalocele in a newborn with trisomy 18. We also show unique prenatal imaging and discuss the importance and limitations of prenatal genetic testing.

  1. Influence of sinogram affirmed iterative reconstruction of CT data on image noise characteristics and low-contrast detectability: an objective approach.

    Directory of Open Access Journals (Sweden)

    Christian von Falck

    Full Text Available OBJECTIVES: To utilize a novel objective approach combining a software phantom and an image quality metric to systematically evaluate the influence of sinogram affirmed iterative reconstruction (SAFIRE of multidetector computed tomography (MDCT data on image noise characteristics and low-contrast detectability (LCD. MATERIALS AND METHODS: A low-contrast and a high-contrast phantom were examined on a 128-slice scanner at different dose levels. The datasets were reconstructed using filtered back projection (FBP and SAFIRE and virtual low-contrast lesions (-20HU were inserted. LCD was evaluated using the multiscale structural similarity index (MS-SIM*. Image noise texture and spatial resolution were objectively evaluated. RESULTS: The use of SAFIRE led to an improvement of LCD for all dose levels and lesions sizes. The relative improvement of LCD was inversely related to the dose level, declining from 208%(±37%, 259%(±30% and 309%(±35% at 25mAs to 106%(±6%, 119%(±9% and 123%(±8% at 200mAs for SAFIRE filter strengths of 1, 3 and 5 (p<0.05. SAFIRE reached at least the LCD of FBP at a relative dose of 50%. There was no statistically significant difference in spatial resolution. The use of SAFIRE led to coarser image noise granularity. CONCLUSION: A novel objective approach combining a software phantom and the MS-SSIM* image quality metric was used to analyze the detectability of virtual low-contrast lesions against the background of image noise as created using SAFIRE in comparison to filtered back-projection. We found, that image noise characteristics using SAFIRE at 50% dose were comparable to the use of FBP at 100% dose with respect to lesion detectability. The unfamiliar imaging appearance of iteratively reconstructed datasets may in part be explained by a different, coarser noise characteristic as demonstrated by a granulometric analysis.

  2. Investigation into the quantitative and qualitative characteristics of choroidal melanoma through magnetic resonance imaging and B-scan ultrasound

    Directory of Open Access Journals (Sweden)

    Papayiannis V

    2017-08-01

    greater mean base diameter compared with those with tumors of low vascularity (P=0.019543. RD was detected in 26 patients through T1-WI sequence, in 13 patients through T2-WI sequence, in 26 patients through T1-WI sequence + contrast, and in 32 patients through ultrasound scan, which proved to be the most sensitive modality.Conclusion: The height of choroidal melanoma was positively correlated with tumor’s homogeneity. Melanomas of greater height were found to be less homogenous, due to increased degeneration and higher occurrence of intratumoral hemorrhage. In addition, choroidal melanoma’s height was also positively correlated with the level of its vascularity. Finally, ultrasound scan was found to be more sensitive than MRI in the detection of RD. Keywords: homogeneity, vascularity, ultrasound scan, MRI, imaging characteristics, retinal detachment

  3. Algumas características das políticas de acreditação e avaliação da educação superior da Colômbia: interfaces com o Brasil Characteristics of accreditation and evaluation policies in columbian higher education: interfaces with Brazil

    Directory of Open Access Journals (Sweden)

    Vicente de Paula Almeida Júnior

    2009-11-01

    Full Text Available Apresentamos, neste artigo, algumas características das políticas de acreditação e de avaliação da educação superior da Colômbia e as suas interfaces com o Brasil. Nosso intuito geral é o de contribuir para o debate referente à reflexão sobre o papel dessas políticas no desenvolvimento dos sistemas de educação superior na região. Especificamente, nos propomos a levantar, comparando com a realidade brasileira, alguns pontos relevantes da Colômbia em relação às múltiplas complexidades nas quais estão inscritos, na atualidade, os temas da acreditação e da avaliação. De modo geral, segundo os estudos parcialmente construídos aqui, os mecanismos de acreditação e avaliação estão na lista de prioridades da agenda governamental e acadêmica tanto na Colômbia quanto no Brasil. Nesse quadro, eles representam o esforço de cooperação internacional na região, porém com dupla finalidade e não isento de contradições: de um lado, para defender os interesses nacionais, dando ênfase na educação superior como bem público sujeito às ações e estratégias do Estado e não do mercado e, de outro, para ampliar a mobilidade estudantil e docente num quadro crescente de mudanças sociais, econômicas e culturais, garantindo e assegurando a qualidade da formação educacional e científica das pessoas.We present in this article some characteristics of accreditation and evaluation policies for higher education in Colombia and their interfaces with Brazil. Our overall aim is to contribute to the debate on the role of policies in the development of higher education systems in the region. Specifically, we propose to raise, in comparison with the Brazilian reality, some relevant points of Colombia relative to the multiple complexities in which the issues of accreditation and evaluation are presently registered. In general, based on the studies partially constructed here, the mechanisms of accreditation and evaluation are in the

  4. #fitspo on Instagram: A mixed-methods approach using Netlytic and photo analysis, uncovering the online discussion and author/image characteristics.

    Science.gov (United States)

    Santarossa, Sara; Coyne, Paige; Lisinski, Carly; Woodruff, Sarah J

    2016-11-01

    The #fitspo 'tag' is a recent trend on Instagram, which is used on posts to motivate others towards a healthy lifestyle through exercise/eating habits. This study used a mixed-methods approach consisting of text and network analysis via the Netlytic program ( N = 10,000 #fitspo posts), and content analysis of #fitspo images ( N = 122) was used to examine author and image characteristics. Results suggest that #fitspo posts may motivate through appearance-mediated themes, as the largest content categories (based on the associated text) were 'feeling good' and 'appearance'. Furthermore, #fitspo posts may create peer influence/support as personal (opposed to non-personal) accounts were associated with higher popularity of images (i.e. number of likes/followers). Finally, most images contained posed individuals with some degree of objectification.

  5. Digital systems to acquire radiological imaging. Characteristics and quality control; Sistemas digitales de adquisicion de imagenes radiograficas. Caracteristicas y Control de Calidad

    Energy Technology Data Exchange (ETDEWEB)

    Torres Cabrera, R.; Hernando Gonzalez, I.

    2006-07-01

    Due to its special characteristics, quality control in digital radiographic systems is very important, even more than in conventional film-screen systems. Differences between digital and analogical images,a in terms of dynamics range, spatial and contrast resolution, and the flexibility of data post-processing require some actions to maintain clinical images in an optimum quality level. Revision 1 of the Spanish Protocol of Quality Control in Diagnostic Radiology includes a chapter dedicated to the quality control of these digital systems for the acquisition of radiographic images. In this paper the different parameters for quality control procedures are described. Also some difficulties to be concerned about (absence of levels of tolerance, access to the raw-data images and related information, availability of use anthropomorphic phantoms, etc, etc) are noted, as well as the most significant aspects of the differences in relation to the ana logical systems. (Author) 15 refs.

  6. Evaluation of diagnostic procedures such as plain-film scintigraphy and MR imaging for spinal metastases in relation to biological characteristics in breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, Hiroya; Nagao, Kazuharu; Nishimura, Reiki; Matsuda, Kazumasa; Baba, Kenichiro; Matsuoka, Yukio; Fukuda, Makoto; Higuchi, Akihiro; Saeki, Takahito [Kumamoto City Hospital (Japan)

    1995-09-01

    The relationship between spinal metastases diagnosed by plain-film, bone scintigraphy, and MR imaging and biological characteristics in 26 patients with breast cancer was investigated retrospectively. It was found that bone scintigraphy is useful for detecting metastases in case with slow-growing tumors determined by DNA polymerase {alpha} or with estrogen-receptor (ER) positivity. In contrast, cases with rapidly growing tumors showed false-negative plain-film or bone scintigraphy results, including cases with ER-negative tumors or DNA polymerase {alpha} of more than 20%. MR imaging was found to be highly sensitive in detecting spinal metastases even in aggressive cases. MR imaging was found to have greater reliability in detecting spinal metastases of breast cancer compared to bone scintigraphy. In conclusion, it may be important to consider the degree of malignancy of each case with spinal metastases of breast cancer in evaluating imaging diagnosis. (author).

  7. Evaluation of diagnostic procedures such as plain-film scintigraphy and MR imaging for spinal metastases in relation to biological characteristics in breast cancer

    International Nuclear Information System (INIS)

    Yamashita, Hiroya; Nagao, Kazuharu; Nishimura, Reiki; Matsuda, Kazumasa; Baba, Kenichiro; Matsuoka, Yukio; Fukuda, Makoto; Higuchi, Akihiro; Saeki, Takahito

    1995-01-01

    The relationship between spinal metastases diagnosed by plain-film, bone scintigraphy, and MR imaging and biological characteristics in 26 patients with breast cancer was investigated retrospectively. It was found that bone scintigraphy is useful for detecting metastases in case with slow-growing tumors determined by DNA polymerase α or with estrogen-receptor (ER) positivity. In contrast, cases with rapidly growing tumors showed false-negative plain-film or bone scintigraphy results, including cases with ER-negative tumors or DNA polymerase α of more than 20%. MR imaging was found to be highly sensitive in detecting spinal metastases even in aggressive cases. MR imaging was found to have greater reliability in detecting spinal metastases of breast cancer compared to bone scintigraphy. In conclusion, it may be important to consider the degree of malignancy of each case with spinal metastases of breast cancer in evaluating imaging diagnosis. (author)

  8. Thyroid volume measurement in external beam radiotherapy patients using CT imaging: correlation with clinical and anthropometric characteristics

    International Nuclear Information System (INIS)

    Veres, C; Garsi, J P; Rubino, C; De Vathaire, F; Diallo, I; Pouzoulet, F; Bidault, F; Chavaudra, J; Bridier, A; Ricard, M; Ferreira, I; Lefkopoulos, D

    2010-01-01

    The aim of this study is to define criteria for accurate representation of the thyroid in human models used to represent external beam radiotherapy (EBRT) patients and evaluate the relationship between the volume of this organ and clinical and anthropometric characteristics. From CT images, we segmented the thyroid gland and calculated its volume for a population of 188 EBRT patients of both sexes, with ages ranging from 1 to 89 years. To evaluate uncertainties linked to measured volumes, experimental studies on the Livermore anthropomorphic phantom were performed. For our population of EBRT patients, we observed that in children, thyroid volume increased rapidly with age, from about 3 cm 3 at 2 years to about 16 cm 3 at 20. In adults, the mean thyroid gland volume was 23.5 ± 9 cm 3 for males and 17.5 ± 8 cm 3 for females. According to anthropometric parameters, the best fit for children was obtained by modeling the log of thyroid volume as a linear function of body surface area (BSA) (p < 0.0001) and age (p = 0.04) and for adults, as a linear function of BSA (p < 0.0001) and gender (p = 0.01). This work enabled us to demonstrate that BSA was the best indicator of thyroid volume for both males and females. These results should be taken into account when modeling the volume of the thyroid in human models used to represent EBRT patients for dosimetry in retrospective studies of the relationship between the estimated dose to the thyroid and long-term follow-up data on EBRT patients. (note)

  9. Paso superior en una ladera

    Directory of Open Access Journals (Sweden)

    Bender, O.

    1965-07-01

    Full Text Available The Redwood highway, through the Californian forest, runs on a viaduct, as it crosses a mountain slope of about 45° inclination. The firm ground is fairly deep, and as an additional constructional difficulty, it was necessary to respect the natural beauty of the countryside. A structure of portal frames were built, forming a number of short spans. These spans were bridged with metal girders, on which a 19 m wide deck was placed. The columns are hollow and have a transversal cross beam, to join each pair. There was difficulty in excavating the foundations for the columns, as it was necessary to dig through the soft top soil, and also prevent this soil from hurting the trunks of the forest trees. Another significant difficulty in the construction of this viaduct was the access to the working site, since there were no suitable platforms from which to operate the appropriate machinery. This made it necessary to do a lot of the work by manual operation. As one of the edges of the deck is very close to the mountain side, a supporting beam was erected on this side. It was made of concrete, on metal piles. The formwork for the deck structure was placed on the concrete stems of the supporting piles.La autopista denominada Redwood (California salva, con un paso superior, la ladera de un bosque cuya pendiente es del 1/1. El terreno firme se halla a bastante profundidad, añadiéndose, a los naturales problemas de la construcción, el imperativo de respetar la belleza agreste del paraje. La solución adoptada consiste en una estructura porticada, con varios tramos de pequeñas luces, salvados con vigas metálicas, sobre los que se coloca la losa del tablero, de 19 m de anchura total. Los soportes están constituidos por pórticos de dos montantes huecos (con bases de hormigón en masa por debajo del suelo, hasta el firme coronados por un cabezal. La perforación de pozos para el hormigonado de los montantes presentaba la dificultad de atravesar el terreno

  10. Measurement of serum isoform [-2]proPSA derivatives shows superior accuracy to magnetic resonance imaging in the diagnosis of prostate cancer in patients with a total prostate-specific antigen level of 2-10 ng/ml.

    Science.gov (United States)

    Furuya, Kazuhiro; Kawahara, Takashi; Narahara, Masaki; Tokita, Takashi; Fukui, Sachi; Imano, Masashi; Mitome, Taku; Ito, Yusuke; Izumi, Koji; Osaka, Kimito; Yokomizo, Yumiko; Hayashi, Narihiko; Hasumi, Hisashi; Nawata, Shintaro; Kawano, Tsuyoshi; Yao, Masahiro; Uemura, Hiroji

    2017-08-01

    More accurate diagnostic procedures for prostate cancer are needed to avoid unnecessary biopsy due to the low specificity of prostate-specific antigen (PSA). Recent studies showed that the percentage of serum isoform [-2]proPSA (p2PSA) to free PSA (%p2PSA), the Prostate Health Index (PHI) and magnetic resonance imaging (MRI) were more accurate than PSA. The aim of this study was to test the accuracy of %p2PSA, PHI and MRI in discriminating patients with and without prostate cancer. The subjects were 50 consecutive men with a PSA level of 2.0-10.0 ng/ml, who underwent prostate biopsy from October 2012 to July 2014. These patients underwent multiparametric MRI before biopsy, and their serum samples were measured for PSA, free PSA and p2PSA. The sensitivity, specificity and accuracy of PHI, %p2PSA and MRI were compared with PSA in the diagnosis of biopsy-confirmed prostate cancer. In a univariate analysis, %p2PSA [area under the curve (AUC): 0.811] and PHI (AUC 0.795) were more accurate than MRI (AUC: 0.583) and PSA (AUC: 0.554) for prostate cancer detection. At 60% sensitivity, the specificity of PHI (76.5%) was higher than that of MRI (52.9%). For significant cancer detection, %p2PSA (AUC: 0.745), PHI (AUC: 0.791) and MRI (AUC: 0.739) were marginally more accurate than PSA (AUC: 0.696). At 85% sensitivity, the specificity of MRI (62.1%) was higher than that of PHI (34.5%). PHI and %p2PSA can be used for screening the general population and MRI can be used for detection of significant cancer in patients suspected, from screening tests, of having prostate cancer.

  11. Frequency-Selective Attention in Auditory Scenes Recruits Frequency Representations Throughout Human Superior Temporal Cortex.

    Science.gov (United States)

    Riecke, Lars; Peters, Judith C; Valente, Giancarlo; Kemper, Valentin G; Formisano, Elia; Sorger, Bettina

    2017-05-01

    A sound of interest may be tracked amid other salient sounds by focusing attention on its characteristic features including its frequency. Functional magnetic resonance imaging findings have indicated that frequency representations in human primary auditory cortex (AC) contribute to this feat. However, attentional modulations were examined at relatively low spatial and spectral resolutions, and frequency-selective contributions outside the primary AC could not be established. To address these issues, we compared blood oxygenation level-dependent (BOLD) responses in the superior temporal cortex of human listeners while they identified single frequencies versus listened selectively for various frequencies within a multifrequency scene. Using best-frequency mapping, we observed that the detailed spatial layout of attention-induced BOLD response enhancements in primary AC follows the tonotopy of stimulus-driven frequency representations-analogous to the "spotlight" of attention enhancing visuospatial representations in retinotopic visual cortex. Moreover, using an algorithm trained to discriminate stimulus-driven frequency representations, we could successfully decode the focus of frequency-selective attention from listeners' BOLD response patterns in nonprimary AC. Our results indicate that the human brain facilitates selective listening to a frequency of interest in a scene by reinforcing the fine-grained activity pattern throughout the entire superior temporal cortex that would be evoked if that frequency was present alone. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  12. 75 FR 28542 - Superior Resource Advisory Committee

    Science.gov (United States)

    2010-05-21

    ... Self-Determination Act (Pub. L. 110-343) and in compliance with the Federal Advisory Committee Act. The purpose of the meeting is to orient the new Superior Resource Advisory Committee members on their roles... following business will be conducted: Overview of the roles and responsibilities of the Superior Resource...

  13. Morphological and qualitative characteristics of the quadriceps muscle of community-dwelling older adults based on ultrasound imaging: classification using latent class analysis.

    Science.gov (United States)

    Kawai, Hisashi; Kera, Takeshi; Hirayama, Ryo; Hirano, Hirohiko; Fujiwara, Yoshinori; Ihara, Kazushige; Kojima, Motonaga; Obuchi, Shuichi

    2018-04-01

    Muscle thickness and echo intensity measured using ultrasound imaging represent both increased muscle volume and connective tissue accumulation. In combination, these ultrasound measurements can be utilized for assessing sarcopenia in community-dwelling older adults. This study aimed to determine whether morphological and qualitative characteristics classified by quadriceps muscle thickness and echo intensity measured using ultrasound are associated with muscle strength, physical function, and sarcopenia in community-dwelling older adults. Quadriceps muscle thickness and echo intensity were measured using ultrasound imaging in 1239 community-dwelling older adults. Latent class analyses were conducted to classify participants based on similarity in the subcutaneous fat thickness (FT), quadriceps muscle thickness (MT), subcutaneous fat echo intensity (FEI), and muscle echo intensity (MEI), which were assessed using ultrasound imaging. Morphological and qualitative characteristics were classified into four types as follows: (A) normal, (B) sarcopenic obesity, (C) obesity, and (D) sarcopenia type. Knee extension strength was significantly greater in A than in B and D. FT and percent body fat were greater in C than in the other types. The correlation between the ultrasound measures and knee extension strength differed among the classification types. The classification types were significantly associated with sarcopenia prevalence. Classification of the morphological and qualitative characteristics obtained from ultrasound imaging may be useful for assessing sarcopenia in community-dwelling older adults.

  14. Agenesia de cava superior associada a bloqueio atrioventricular de 3º grau Agenesis of the right superior vena cava associated with total heart block

    Directory of Open Access Journals (Sweden)

    Gustavo J. Ventura Couto

    2008-03-01

    Full Text Available A persistência de veia cava superior esquerda com ausência da veia cava superior é uma anomalia rara, principalmente quando associada a bloqueio atrioventricular de 3º grau. Relatamos o caso de uma paciente, na qual durante implante de marca-passo definitivo, para a correção de bloqueio atrioventricular total, foi detectada presença de veia cava superior esquerda com suspeição de ausência de veia cava superior, o que levou ao emprego de técnica diferenciada para fixação do eletrodo ventricular. Para confirmação da provável agenesia, foram realizados diversos exames complementares de imagem, demonstrando-se a dificuldade no diagnóstico da síndrome aqui descrita.The superior left vena cava with the absent superior vena cava is a rare abnormality, especially when associated with total heart block. We report a case of a patient in which the presence of superior left vena cava and the absence of the superior vena cava was detected during the implantation of a pacemaker for the correction of a total heart block, which led us to use a different technique for the fixation of the ventricular electrode. To confirm the supposed absence, several image exams were made showing the difficulty on the diagnosis of the described syndrome.

  15. Magnetic resonance perfusion and diffusion imaging characteristics of transient bone marrow edema, avascular necrosis and subchondral insufficiency fractures of the proximal femur

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Dirk, E-mail: d.mueller@uk-koeln.de [Department of Radiology, University of Cologne (Germany); Department of Radiology, Technische Universität München (Germany); Schaeffeler, Christoph, E-mail: schaeffeler@me.com [Department of Radiology, Cantonal Hospital Graubuenden, Chur (Switzerland); Department of Radiology, Cantonal Hospital Graubuenden, Chur (Switzerland); Baum, Thomas, E-mail: thomas-baum@gmx.de [Department of Radiology, Technische Universität München (Germany); Walter, Flavia, E-mail: flavia_walter2000@yahoo.de [Department of Radiology, Technische Universität München (Germany); Rechl, Hans, E-mail: rechl@tum.de [Department of Orthopaedics, Technische Universität München (Germany); Rummeny, Ernst J., E-mail: rummeny@tum.de [Department of Radiology, Technische Universität München (Germany); Woertler, Klaus, E-mail: klaus.woertler@tum.de [Department of Radiology, Technische Universität München (Germany)

    2014-10-15

    Highlights: • DCE-MRI may add information to the pathophysiology of bone marrow edema (BME) of the proximal femur. • Patients with transient bone marrow edema (TBME) or subchondral insufficiency fractures (SIF) and avascular osteonecrosis (AVN) showed different MR perfusion patterns. • Perfusion characteristics suggest different pathophysiology for AVN compared with TBME or SIF. • Diffusion weighted imaging (DWI) was not able to discriminate necrotic from edematous bone marrow. • DWI is of limited value to evaluate BME of the proximal femur. - Abstract: Purpose: To evaluate magnetic resonance (MR) perfusion and diffusion imaging characteristics in patients with transient bone marrow edema (TBME), avascular necrosis (AVN), or subchondral insufficiency fractures (SIF) of the proximal femur. Materials and methods: 29 patients with painful hip and bone marrow edema pattern of the proximal femur on non-contrast MR imaging were examined using diffusion-weighted and dynamic gadolinium-enhanced sequences. Apparent diffusion coefficients (ADCs) and perfusion parameters were calculated for different regions of the proximal femur. Regional distribution and differences in ADC values and perfusion parameters were evaluated. Results: Seven patients presented with TBME, 15 with AVN and seven with SIF of the proximal femur. Perfusion imaging showed significant differences for maximum enhancement values (E{sub max}), slope (E{sub slope}) and time to peak (TTP) between the three patient groups (p < 0.05). In contrast, no significant differences for ADC values were calculated when comparing TBME, AVN, and SIF patients. Conclusion: Diffusion weighted imaging of bone marrow of the proximal femur did not show significant differences between patients with TBME, AVN or SIF. In contrast, MR perfusion imaging demonstrated significant differences for the different patient groups and may as a complementary imaging technique add information to the understanding of the pathophysiology

  16. Magnetic resonance perfusion and diffusion imaging characteristics of transient bone marrow edema, avascular necrosis and subchondral insufficiency fractures of the proximal femur

    International Nuclear Information System (INIS)

    Mueller, Dirk; Schaeffeler, Christoph; Baum, Thomas; Walter, Flavia; Rechl, Hans; Rummeny, Ernst J.; Woertler, Klaus

    2014-01-01

    Highlights: • DCE-MRI may add information to the pathophysiology of bone marrow edema (BME) of the proximal femur. • Patients with transient bone marrow edema (TBME) or subchondral insufficiency fractures (SIF) and avascular osteonecrosis (AVN) showed different MR perfusion patterns. • Perfusion characteristics suggest different pathophysiology for AVN compared with TBME or SIF. • Diffusion weighted imaging (DWI) was not able to discriminate necrotic from edematous bone marrow. • DWI is of limited value to evaluate BME of the proximal femur. - Abstract: Purpose: To evaluate magnetic resonance (MR) perfusion and diffusion imaging characteristics in patients with transient bone marrow edema (TBME), avascular necrosis (AVN), or subchondral insufficiency fractures (SIF) of the proximal femur. Materials and methods: 29 patients with painful hip and bone marrow edema pattern of the proximal femur on non-contrast MR imaging were examined using diffusion-weighted and dynamic gadolinium-enhanced sequences. Apparent diffusion coefficients (ADCs) and perfusion parameters were calculated for different regions of the proximal femur. Regional distribution and differences in ADC values and perfusion parameters were evaluated. Results: Seven patients presented with TBME, 15 with AVN and seven with SIF of the proximal femur. Perfusion imaging showed significant differences for maximum enhancement values (E max ), slope (E slope ) and time to peak (TTP) between the three patient groups (p < 0.05). In contrast, no significant differences for ADC values were calculated when comparing TBME, AVN, and SIF patients. Conclusion: Diffusion weighted imaging of bone marrow of the proximal femur did not show significant differences between patients with TBME, AVN or SIF. In contrast, MR perfusion imaging demonstrated significant differences for the different patient groups and may as a complementary imaging technique add information to the understanding of the pathophysiology of

  17. Facile synthesis of carbon dots with superior sensing ability

    Science.gov (United States)

    Jin, Lin; Li, Jingguo; Liu, Liyun; Wang, Zhenling; Zhang, Xingcai

    2018-04-01

    Carbon dots (CDs) have various applications in biomedical and environmental field, such as bio-imaging, bio-sensing and heavy metal detection. In this study, a novel class of CDs were synthesized using a one-step hydrothermal method. The fabricated CDs displayed stable photoluminescence, good water solubility, and photo stability. Moreover, the functional groups (carboxylic acid moieties and hydroxyls) on the surface of the obtained CDs enable it with superior sensing ability (e.g., very low detectable concentration for Pb2+: 5 nmol/L). With superior detection sensitivity, excellent fluorescent properties and facile fabrication method, the as-obtained CDs can find practical applications as cost-effective and sensitive chemo-sensors in water and food safety field.

  18. Physiological models of the lateral superior olive.

    Directory of Open Access Journals (Sweden)

    Go Ashida

    2017-12-01

    Full Text Available In computational biology, modeling is a fundamental tool for formulating, analyzing and predicting complex phenomena. Most neuron models, however, are designed to reproduce certain small sets of empirical data. Hence their outcome is usually not compatible or comparable with other models or datasets, making it unclear how widely applicable such models are. In this study, we investigate these aspects of modeling, namely credibility and generalizability, with a specific focus on auditory neurons involved in the localization of sound sources. The primary cues for binaural sound localization are comprised of interaural time and level differences (ITD/ILD, which are the timing and intensity differences of the sound waves arriving at the two ears. The lateral superior olive (LSO in the auditory brainstem is one of the locations where such acoustic information is first computed. An LSO neuron receives temporally structured excitatory and inhibitory synaptic inputs that are driven by ipsi- and contralateral sound stimuli, respectively, and changes its spike rate according to binaural acoustic differences. Here we examine seven contemporary models of LSO neurons with different levels of biophysical complexity, from predominantly functional ones ('shot-noise' models to those with more detailed physiological components (variations of integrate-and-fire and Hodgkin-Huxley-type. These models, calibrated to reproduce known monaural and binaural characteristics of LSO, generate largely similar results to each other in simulating ITD and ILD coding. Our comparisons of physiological detail, computational efficiency, predictive performances, and further expandability of the models demonstrate (1 that the simplistic, functional LSO models are suitable for applications where low computational costs and mathematical transparency are needed, (2 that more complex models with detailed membrane potential dynamics are necessary for simulation studies where sub

  19. Superiority in value and the repugnant conclusion

    DEFF Research Database (Denmark)

    Jensen, Karsten Klint

    2007-01-01

    superiority does not amount to a radical value difference at all. I then spell out the consequences of these results for different interpretations of Griffin's suggestion regarding population ethics. None of them comes out very successful, but perhaps they nevertheless retain some interest.......James Griffin has considered a weak form of superiority in value a possible remedy to the Repugnant Conclusion. In this paper, I demonstrate that, in a context where value is additive, this weaker form collapses into a stronger form of superiority. And in a context where value is non-additive, weak...

  20. Characteristics of Successful Entrepreneurs.

    Science.gov (United States)

    McClelland, David C.

    1987-01-01

    Comparison of characteristics of 12 average and 12 superior small business people in three developing nations (India, Malawi, and Ecuador) found proactive qualities such as initiative and assertiveness, achievement orientation, and commitment to others characteristic of successful entrepreneurs. Other expected qualities (self-confidence,…

  1. Superior mesenteric vein rotation: a CT sign of midgut malrotation

    International Nuclear Information System (INIS)

    Nichols, D.M.; Li, D.K.

    1983-01-01

    Computed tomography (CT) of the pancreas, with its excellent display of peripancreatic anatomy, allows visualization of the major vessels entering the mesenteric root. In scans of the normal upper abdomen obtained at or just below the level of the uncinate process of the pancreas, the proximal superior mesenteric vein (SMV) easily can be identified lying on the right ventral aspect of the superior mesenteric artery (SMA). The authors have observed a characteristic abnormality in this normal vascular arrangement on CT scans of the pancreas in three adult patients with suspected chronic pancreatitis who were subsequently proved to have midgut malrotation. They called this the SMV rotation sign and believe that its detection even on CT scans limited to the level of the pancreas should alert the radiologist to the presence of a midgut malrotation that may have been unsuspected

  2. Improved diagnostic performance of exercise thallium-201 single photon emission computed tomography over planar imaging in the diagnosis of coronary artery disease: a receiver operating characteristic analysis

    International Nuclear Information System (INIS)

    Fintel, D.J.; Links, J.M.; Brinker, J.A.; Frank, T.L.; Parker, M.; Becker, L.C.

    1989-01-01

    Qualitative interpretation of tomographic and planar scintigrams, a five point rating scale and receiver operating characteristic analysis were utilized to compare single photon emission computed tomography and conventional planar imaging of myocardial thallium-201 uptake in the accuracy of the diagnosis of coronary artery disease and individual vessel involvement. One hundred twelve patients undergoing cardiac catheterization and 23 normal volunteers performed symptom-limited treadmill exercise, followed by stress and redistribution imaging by both tomographic and planar techniques, with the order determined randomly. Paired receiver operating characteristic curves revealed that single photon emission computed tomography was more accurate than planar imaging over the entire range of decision thresholds for the overall detection and exclusion of coronary artery disease and involvement of the left anterior descending and left circumflex coronary arteries. Tomography offered relatively greater advantages in male patients and in patients with milder forms of coronary artery disease, who had no prior myocardial infarction, only single vessel involvement or no lesion greater than or equal to 50 to 69%. Tomography did not appear to provide improved diagnosis in women or in detection of disease in the right coronary artery. Although overall detection of coronary artery disease was not improved in patients with prior myocardial infarction, tomography provided improved identification of normal and abnormal vascular regions. These results indicate that single photon emission computed tomography provides improved diagnostic performance compared with planar imaging in many clinical subgroups

  3. Superior mesenteric artery syndrome causing growth retardation

    Directory of Open Access Journals (Sweden)

    Halil İbrahim Taşcı

    2013-03-01

    Full Text Available Superior mesenteric artery syndrome is a rare and lifethreateningclinical condition caused by the compressionof the third portion of the duodenum between the aortaand the superior mesenteric artery’s proximal part. Thiscompression may lead to chronic intermittent, acute totalor partial obstruction. Sudden weight-loss and the relateddecrease in the fat tissue are considered to be the etiologicalreason of acute stenosis. Weight-loss accompaniedby nausea, vomiting, anorexia, epigastric pain, andbloating are the leading complaints. Barium radiographs,computerized tomography, conventional angiography,tomographic and magnetic resonance angiography areused in the diagnosis. There are medical and surgical approachesto treatment. We hereby present the case ofa patient with superior mesenteric artery syndrome withdelayed diagnosis.Key words: superior mesenteric artery syndrome, nausea-vomiting, anorexia

  4. Superior semicircular canal dehiscence in relation to the superior petrosal sinus: a potential cause of pulsatile tinnitus

    International Nuclear Information System (INIS)

    Liu, Z.; Bi, W.; Li, J.; Li, Q.; Dong, C.; Zhao, P.; Lv, H.; Wang, Z.

    2015-01-01

    Aim: To examine the association between superior semicircular canal dehiscence (SSCD) and pulsatile tinnitus (PT). Materials and methods: Two SSCD groups included 408 unilateral persistent PT patients, and 511 controls undergoing head and neck dual-phase contrast-enhanced computed tomography (DP-CECT) for reasons other than PT. The prevalence of type I (no the superior petrosal sinus running through the dehiscence) and type II (superior semicircular canal dehiscence in relation to the superior petrosal sinus) SSCD was analysed using chi-square test. Results: SSCD was identified in 5.1% (21/408) of PT ears, significantly different from 2% (8/408) of non-PT ears and 0.7% (7/1022) of controls. There was no significant difference in SSCD prevalence between non-PT ears in the PT group and controls. In the PT group, 15/21 ears were type II SSCD; 6/21 ears were type I. Fifteen combined non-PT and control ears with SSCD included two type II and 13 type I SSCD. The prevalence of type II SSCD in PT ears was significantly higher than that of non-PT ears in both groups, and the prevalence of type I SSCD in PT ears was similar to that of non-PT ears in both groups. Conclusion: Compared with type I SSCD, there may be a causal relationship between type II SSCD and PT. -- Highlights: •The prevalence of type II SSCD in PT ears was significantly higher than that in non-PT ears in both the PT group and controls. •The prevalence of type I SSCD was similar among the PT ears and non-PT ears. •The superior petrosal sinus running through the dehiscence may be essential for SSCD to induce PT. •Venous phase CT images with bone window settings is the modality method to differentiate type II from type I SSCD

  5. THE ASSOCIATION BETWEEN MENSTRUAL CYCLE CHARACTERISTICS AND PERCEIVED BODY IMAGE: A CROSS-SECTIONAL SURVEY OF POLISH FEMALE ADOLESCENTS.

    Science.gov (United States)

    Kaczmarek, Maria; Trambacz-Oleszak, Sylwia

    2016-05-01

    The increasing prevalence of negative body perceptions among adolescent girls and the tendency towards wishing to be thinner have become a cultural norm in Western culture. Adolescent girls are particularly vulnerable to developing a negative body image due to physical and sexual changes occurring during puberty. This study aimed to evaluate the association between different measures of body image perceptions and different phases of the menstrual cycle after controlling for weight status and other potential confounders in Polish adolescent girls aged 12-18 years. Three-hundred and thirty participants of a cross-sectional survey conducted in 2009, normally cycling and with no eating disorders, completed a background questionnaire and the Stunkard Figure Rating Scale, and their anthropometric measurements were collected. The dependent outcome variables were measures of body image (actual body image, ideal body image and ideal-self discrepancy) and dichotomous body image perception (satisfied versus dissatisfied) adjusted for other predictor factors: socio-demographic variables, menstrual history and cycle phases, and weight status. One-way ANOVA indicated that weight status, age at menarche and menstrual cycle phase were associated with actual body image and rate of ideal-self discrepancy. Ideal body image was associated with weight status and menstrual cycle phase. General logistic regression models were constructed to evaluate associations of body dissatisfaction and all potential predictor variables. The final selected model of the multiple logistic regression analysis using the backward elimination procedure revealed that adjusted for other factors, negative body image was significantly associated with different phases of the menstrual cycle (p trend=0.033) and increasing body weight status (p trend=0.0007). The likelihood of body dissatisfaction was greatest during the premenstrual phase of the menstrual cycle (OR=2.38; 95% CI 1.06, 5.32) and among girls in

  6. Visual search for emotional expressions: Effect of stimulus set on anger and happiness superiority.

    Science.gov (United States)

    Savage, Ruth A; Becker, Stefanie I; Lipp, Ottmar V

    2016-01-01

    Prior reports of preferential detection of emotional expressions in visual search have yielded inconsistent results, even for face stimuli that avoid obvious expression-related perceptual confounds. The current study investigated inconsistent reports of anger and happiness superiority effects using face stimuli drawn from the same database. Experiment 1 excluded procedural differences as a potential factor, replicating a happiness superiority effect in a procedure that previously yielded an anger superiority effect. Experiments 2a and 2b confirmed that image colour or poser gender did not account for prior inconsistent findings. Experiments 3a and 3b identified stimulus set as the critical variable, revealing happiness or anger superiority effects for two partially overlapping sets of face stimuli. The current results highlight the critical role of stimulus selection for the observation of happiness or anger superiority effects in visual search even for face stimuli that avoid obvious expression related perceptual confounds and are drawn from a single database.

  7. Imaging characteristics of toxoplasmosis encephalitis after bone marrow transplantation: report of two cases and review of the literature

    International Nuclear Information System (INIS)

    Mueller-Mang, C.; Mang, T.G.; Thurnher, M.M.; Kalhs, P.

    2006-01-01

    Toxoplasmosis encephalitis is a severe, but often misdiagnosed complication in patients after bone marrow transplantation (BMT). We describe the unique computed tomography (CT) and magnetic resonance (MR) imaging features of cerebral toxoplasmosis in two bone marrow recipients and compare them to the cases in the literature. To our knowledge, this is the first report analyzing the appearance of cerebral toxoplasmosis on diffusion-weighted MR imaging (DWI). (orig.)

  8. Imaging characteristics of toxoplasmosis encephalitis after bone marrow transplantation: report of two cases and review of the literature

    Energy Technology Data Exchange (ETDEWEB)

    Mueller-Mang, C.; Mang, T.G.; Thurnher, M.M. [University Hospital Vienna, Department of Radiology, Vienna (Austria); Kalhs, P. [University Hospital Vienna, Department of Internal Medicine, Vienna (Austria)

    2006-02-15

    Toxoplasmosis encephalitis is a severe, but often misdiagnosed complication in patients after bone marrow transplantation (BMT). We describe the unique computed tomography (CT) and magnetic resonance (MR) imaging features of cerebral toxoplasmosis in two bone marrow recipients and compare them to the cases in the literature. To our knowledge, this is the first report analyzing the appearance of cerebral toxoplasmosis on diffusion-weighted MR imaging (DWI). (orig.)

  9. Brain Abscess Associated with Isolated Left Superior Vena Cava Draining into the Left Atrium in the Absence of Coronary Sinus and Atrial Septal Defect

    International Nuclear Information System (INIS)

    Erol, Ilknur; Cetin, I. Ilker; Alehan, Fuesun; Varan, Birguel; Ozkan, Sueleyman; Agildere, A. Muhtesem; Tokel, Kursad

    2006-01-01

    A previously healthy 12-year-old girl presented with severe headache for 2 weeks. On physical examination, there was finger clubbing without apparent cyanosis. Neurological examination revealed only papiledema without focal neurologic signs. Cerebral magnetic resonance imaging showed the characteristic features of brain abscess in the left frontal lobe. Cardiologic workup to exclude a right-to-left shunt showed an abnormality of the systemic venous drainage: presence of isolated left superior vena cava draining into the left atrium in the absence of coronary sinus and atrial septal defect. This anomaly is rare, because only a few other cases have been reported

  10. Optimisation of the imaging and dosimetric characteristics of an electronic portal imaging device employing plastic scintillating fibres using Monte Carlo simulations.

    Science.gov (United States)

    Blake, S J; McNamara, A L; Vial, P; Holloway, L; Kuncic, Z

    2014-11-21

    A Monte Carlo model of a novel electronic portal imaging device (EPID) has been developed using Geant4 and its performance for imaging and dosimetry applications in radiotherapy has been characterised. The EPID geometry is based on a physical prototype under ongoing investigation and comprises an array of plastic scintillating fibres in place of the metal plate/phosphor screen in standard EPIDs. Geometrical and optical transport parameters were varied to investigate their impact on imaging and dosimetry performance. Detection efficiency was most sensitive to variations in fibre length, achieving a peak value of 36% at 50 mm using 400 keV x-rays for the lengths considered. Increases in efficiency for longer fibres were partially offset by reductions in sensitivity. Removing the extra-mural absorber surrounding individual fibres severely decreased the modulation transfer function (MTF), highlighting its importance in maximising spatial resolution. Field size response and relative dose profile simulations demonstrated a water-equivalent dose response and thus the prototype's suitability for dosimetry applications. Element-to-element mismatch between scintillating fibres and underlying photodiode pixels resulted in a reduced MTF for high spatial frequencies and quasi-periodic variations in dose profile response. This effect is eliminated when fibres are precisely matched to underlying pixels. Simulations strongly suggest that with further optimisation, this prototype EPID may be capable of simultaneous imaging and dosimetry in radiotherapy.

  11. Optimisation of the imaging and dosimetric characteristics of an electronic portal imaging device employing plastic scintillating fibres using Monte Carlo simulations

    Science.gov (United States)

    Blake, S. J.; McNamara, A. L.; Vial, P.; Holloway, L.; Kuncic, Z.

    2014-11-01

    A Monte Carlo model of a novel electronic portal imaging device (EPID) has been developed using Geant4 and its performance for imaging and dosimetry applications in radiotherapy has been characterised. The EPID geometry is based on a physical prototype under ongoing investigation and comprises an array of plastic scintillating fibres in place of the metal plate/phosphor screen in standard EPIDs. Geometrical and optical transport parameters were varied to investigate their impact on imaging and dosimetry performance. Detection efficiency was most sensitive to variations in fibre length, achieving a peak value of 36% at 50 mm using 400 keV x-rays for the lengths considered. Increases in efficiency for longer fibres were partially offset by reductions in sensitivity. Removing the extra-mural absorber surrounding individual fibres severely decreased the modulation transfer function (MTF), highlighting its importance in maximising spatial resolution. Field size response and relative dose profile simulations demonstrated a water-equivalent dose response and thus the prototype’s suitability for dosimetry applications. Element-to-element mismatch between scintillating fibres and underlying photodiode pixels resulted in a reduced MTF for high spatial frequencies and quasi-periodic variations in dose profile response. This effect is eliminated when fibres are precisely matched to underlying pixels. Simulations strongly suggest that with further optimisation, this prototype EPID may be capable of simultaneous imaging and dosimetry in radiotherapy.

  12. Concomitant Persistent Left Superior Vena Cava and Horseshoe Kidney

    Directory of Open Access Journals (Sweden)

    Faraz Jaffer

    2015-01-01

    Full Text Available Persistent left superior vena cava (PLSVC and horseshoe kidney (HSK are common congenital abnormalities; however presence of both in the same person is extremely rare. A patient with hepatitis C cirrhosis awaiting transplant presented with worsening liver dysfunction, diagnosed with acute renal failure secondary to hepatorenal syndrome, and required X-ray fluoroscopy guided tunneled venous catheter placement for hemodialysis. Review of imaging studies demonstrated coexistence of PLSVC and HSK. PLSVC in adulthood is usually incidental with the most common drainage pattern being without physiologic dysfunction. Isolated horseshoe kidney is still the most common of renal fusion anomalies; however etiology of coexistent PLSVC remains unknown.

  13. Imaging

    International Nuclear Information System (INIS)

    Kellum, C.D.; Fisher, L.M.; Tegtmeyer, C.J.

    1987-01-01

    This paper examines the advantages of the use of excretory urography for diagnosis. According to the authors, excretory urography remains the basic radiologic examination of the urinary tract and is the foundation for the evaluation of suspected urologic disease. Despite development of the newer diagnostic modalities such as isotope scanning, ultrasonography, CT, and magnetic resonsance imaging (MRI), excretory urography has maintained a prominent role in ruorradiology. Some indications have been altered and will continue to change with the newer imaging modalities, but the initial evaluation of suspected urinary tract structural abnormalities; hematuria, pyuria, and calculus disease is best performed with excretory urography. The examination is relatively inexpensive and simple to perform, with few contraindictions. Excretory urography, when properly performed, can provide valuable information about the renal parenchyma, pelvicalyceal system, ureters, and urinary bladder

  14. MR imaging of the brain in neurofibromatosis

    International Nuclear Information System (INIS)

    Kuhn, J.P.; Cohen, M.L.; Duffner, P.K.; Seidel, F.; Harwood-Nash, D.

    1986-01-01

    Fifteen children and young adults with neurofibromatosis underwent CT and MR imaging (0.5-T superconducting magnet). Seven had optic gliomas and five had other intracranial neoplasms. Before thin-section MR imaging became available, CT was superior for demonstrating the optic nerves, although MR imaging better delineated tumor spread to the optic chiasm and tract. MR imaging was superior for demonstrating other gliomatous lesions associated with neurofibromatosis. Most lesions had long T1 and T2 values and were best seen on T2-weighted