Clinical advantages of three dimensional cine cardiac images

International Nuclear Information System (INIS)

Kinosada, Yasutomi; Okuda, Yasuyuki; Nakagawa, Tsuyoshi; Itou, Takafumi; Hattori, Takao.

1996-01-01

We evaluated clinical advantages and the quantitativeness of computerized three-dimensional (3D) cinematic images of a human heart, which were produced with a set of magnetic resonance (MR) images by using the computer graphic technique. Many contiguous, multi-location and multi-phase short axis images were obtained with the ECG gated conventional and fast cardiac imaging sequences in normal volunteers and selected patients with myocardial infarction, hypertrophic cardiomyopathy, dilated cardiomyopathy and left ventricular dysfunction. Judging by visual impressions of the computerized 3D cinematic cardiac images, we could easily understand and evaluate the myocardial motions or the anatomic and volumetric changes of a heart according to the cardiac phases. These images were especially useful to compare the wall motion, the left ventricular ejection-fraction (LVEF), or other cardiac functions and conditions between before and after therapeutic procedures such as percutaneous transluminal coronary angioplasty for patients with myocardial infarction. A good correlation between the LVEF calculated from a set of computerized 3D cinematic images and the ultra sound examinations were found. The results of our study showed that computerized 3D cinematic cardiac images were clinically useful to understand the myocardial motions qualitatively and to evaluate cardiac functions such as the LVEF quantitatively. (author)

[Clinical use of interventional MR imaging].

Science.gov (United States)

Kahn, Thomas; Schulz, Thomas; Moche, Michael; Prothmann, Sascha; Schneider, Jens-Peter

2003-01-01

The integration of diagnostic and therapeutic procedures by MRI is based on the combination of excellent morphologic and functional imaging. The spectrum of MR-guided interventions includes biopsies, thermal ablation procedures, vascular applications, and intraoperative MRI. In all these applications, different scientific groups have obtained convincing results in basic developments as well as in clinical use. Interventional MRI (iMRI) is expected to attain an important role in interventional radiology, minimal invasive therapy, and monitoring of surgical procedures.

Secondary electron images obtained with a standard PEEM set up

International Nuclear Information System (INIS)

Benka, O.; Zeppenfeld, P.

2004-01-01

Secondary electron images excited by 3 to 4.3 keV electrons are obtained with a standard photoelectron electron emission microscope (PEEM) set up equipped with an imaging energy filter (IEF). The electron gun was mounted on a standard PEEM entrance flange at an angle of 25 o with respect to the sample surface. A low extraction voltage of 500 V was used to minimize the deflection of the electron beam by the PEEM extraction electrode. The secondary electron images are compared to photoelectron images excited by a standard 4.9 eV UV lamp. In the case of a Cu pattern on a Si substrate it is found that the lateral resolution without the IEF is about the same for electron and photon excitation but that the relative electron emission intensities are very different. The use of the IEF-reduces the lateral resolution. Images for secondary electron energies between eV 1 and eV 2 were obtained by setting the IEF to -V 1 and -V 2 ∼ -(V 1 + 5V) potentials and taking the difference of both images. Images up to 100 eV electron energies were recorded. The lateral resolution is in the range of μm. The material contrast obtained in these difference images are discussed in terms of a secondary electron and photoelectron emission model and secondary electron energy spectra measured with a LEED-Auger spectrometer. (author)

Brain imaging with synthetic MR in children: clinical quality assessment

Energy Technology Data Exchange (ETDEWEB)

Betts, Aaron M.; Serai, Suraj [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Leach, James L.; Jones, Blaise V. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); University of Cincinnati College of Medicine, Cincinnati, OH (United States); Zhang, Bin [Cincinnati Children' s Hospital Medical Center, Biostatistics and Epidemiology, Cincinnati, OH (United States)

2016-10-15

Synthetic magnetic resonance imaging is a quantitative imaging technique that measures inherent T1-relaxation, T2-relaxation, and proton density. These inherent tissue properties allow synthesis of various imaging sequences from a single acquisition. Clinical use of synthetic MR imaging has been described in adult populations. However, use of synthetic MR imaging has not been previously reported in children. The purpose of this study is to report our assessment of diagnostic image quality using synthetic MR imaging in children. Synthetic MR acquisition was obtained in a sample of children undergoing brain MR imaging. Image quality assessments were performed on conventional and synthetic T1-weighted, T2-weighted, and FLAIR images. Standardized linear measurements were performed on conventional and synthetic T2 images. Estimates of patient age based upon myelination patterns were also performed. Conventional and synthetic MR images were evaluated on 30 children. Using a 4-point assessment scale, conventional imaging performed better than synthetic imaging for T1-weighted, T2-weighted, and FLAIR images. When the assessment was simplified to a dichotomized scale, the conventional and synthetic T1-weighted and T2-weighted images performed similarly. However, the superiority of conventional FLAIR images persisted in the dichotomized assessment. There were no statistically significant differences between linear measurements made on T2-weighted images. Estimates of patient age based upon pattern of myelination were also similar between conventional and synthetic techniques. Synthetic MR imaging may be acceptable for clinical use in children. However, users should be aware of current limitations that could impact clinical utility in the software version used in this study. (orig.)

Adaptive Optical System for Retina Imaging Approaches Clinic Applications

Science.gov (United States)

Ling, N.; Zhang, Y.; Rao, X.; Wang, C.; Hu, Y.; Jiang, W.; Jiang, C.

We presented "A small adaptive optical system on table for human retinal imaging" at the 3rd Workshop on Adaptive Optics for Industry and Medicine. In this system, a 19 element small deformable mirror was used as wavefront correction element. High resolution images of photo receptors and capillaries of human retina were obtained. In recent two years, at the base of this system a new adaptive optical system for human retina imaging has been developed. The wavefront correction element is a newly developed 37 element deformable mirror. Some modifications have been adopted for easy operation. Experiments for different imaging wavelengths and axial positions were conducted. Mosaic pictures of photoreceptors and capillaries were obtained. 100 normal and abnormal eyes of different ages have been inspected.The first report in the world concerning the most detailed capillary distribution images cover ±3° by ± 3° field around the fovea has been demonstrated. Some preliminary very early diagnosis experiment has been tried in laboratory. This system is being planned to move to the hospital for clinic experiments.

Radiology clinical synopsis: a simple solution for obtaining an adequate clinical history for the accurate reporting of imaging studies on patients in intensive care units

International Nuclear Information System (INIS)

Cohen, Mervyn D.; Alam, Khurshaid

2005-01-01

Lack of clinical history on radiology requisitions is a universal problem. We describe a simple Web-based system that readily provides radiology-relevant clinical history to the radiologist reading radiographs of intensive care unit (ICU) patients. Along with the relevant history, which includes primary and secondary diagnoses, disease progression and complications, the system provides the patient's name, record number and hospital location. This information is immediately available to reporting radiologists. New clinical information is immediately entered on-line by the radiologists as they are reviewing images. After patient discharge, the data are stored and immediately available if the patient is readmitted. The system has been in routine clinical use in our hospital for nearly 2 years. (orig.)

Practical Considerations for Clinical PET/MR Imaging.

Science.gov (United States)

Galgano, Samuel; Viets, Zachary; Fowler, Kathryn; Gore, Lael; Thomas, John V; McNamara, Michelle; McConathy, Jonathan

2018-01-01

Clinical PET/MR imaging is currently performed at a number of centers around the world as part of routine standard of care. This article focuses on issues and considerations for a clinical PET/MR imaging program, focusing on routine standard-of-care studies. Although local factors influence how clinical PET/MR imaging is implemented, the approaches and considerations described here intend to apply to most clinical programs. PET/MR imaging provides many more options than PET/computed tomography with diagnostic advantages for certain clinical applications but with added complexity. A recurring theme is matching the PET/MR imaging protocol to the clinical application to balance diagnostic accuracy with efficiency. Copyright © 2017 Elsevier Inc. All rights reserved.

Clinical photoacoustic imaging of cancer

Energy Technology Data Exchange (ETDEWEB)

Valluru, Keerthi S.; Willmann, Juergen K. [Dept. of Radiology, Molecular Imaging Program at Stanford, Stanford University School of Medicine, Stanford (United States)

2016-08-15

Photoacoustic imaging is a hybrid technique that shines laser light on tissue and measures optically induced ultrasound signal. There is growing interest in the clinical community over this new technique and its possible clinical applications. One of the most prominent features of photoacoustic imaging is its ability to characterize tissue, leveraging differences in the optical absorption of underlying tissue components such as hemoglobin, lipids, melanin, collagen and water among many others. In this review, the state-of-the-art photoacoustic imaging techniques and some of the key outcomes pertaining to different cancer applications in the clinic are presented.

An integral design strategy combining optical system and image processing to obtain high resolution images

Science.gov (United States)

Wang, Jiaoyang; Wang, Lin; Yang, Ying; Gong, Rui; Shao, Xiaopeng; Liang, Chao; Xu, Jun

2016-05-01

In this paper, an integral design that combines optical system with image processing is introduced to obtain high resolution images, and the performance is evaluated and demonstrated. Traditional imaging methods often separate the two technical procedures of optical system design and imaging processing, resulting in the failures in efficient cooperation between the optical and digital elements. Therefore, an innovative approach is presented to combine the merit function during optical design together with the constraint conditions of image processing algorithms. Specifically, an optical imaging system with low resolution is designed to collect the image signals which are indispensable for imaging processing, while the ultimate goal is to obtain high resolution images from the final system. In order to optimize the global performance, the optimization function of ZEMAX software is utilized and the number of optimization cycles is controlled. Then Wiener filter algorithm is adopted to process the image simulation and mean squared error (MSE) is taken as evaluation criterion. The results show that, although the optical figures of merit for the optical imaging systems is not the best, it can provide image signals that are more suitable for image processing. In conclusion. The integral design of optical system and image processing can search out the overall optimal solution which is missed by the traditional design methods. Especially, when designing some complex optical system, this integral design strategy has obvious advantages to simplify structure and reduce cost, as well as to gain high resolution images simultaneously, which has a promising perspective of industrial application.

Comparison of 3 T and 7 T MRI clinical sequences for ankle imaging

Energy Technology Data Exchange (ETDEWEB)

Juras, Vladimir, E-mail: vladimir.juras@meduniwien.ac.at [Medical University of Vienna, Department of Radiology, Vienna General Hospital, Waeringer Guertel 18-20, A-1090 Vienna (Austria); Slovak Academy of Sciences, Institute of Measurement Science, Dubravska cesta 9, 84104 Bratislava (Slovakia); Welsch, Goetz, E-mail: welsch@bwh.harvard.edu [Medical University of Vienna, Department of Radiology, Vienna General Hospital, Waeringer Guertel 18-20, A-1090 Vienna (Austria); Baer, Peter, E-mail: baerpeter@siemens.com [Siemens Healthcare, Richard-Strauss-Strasse 76, D81679 Munich (Germany); Kronnerwetter, Claudia, E-mail: claudia.kronnerwetter@meduniwien.ac.at [Medical University of Vienna, Department of Radiology, Vienna General Hospital, Waeringer Guertel 18-20, A-1090 Vienna (Austria); Fujita, Hiroyuki, E-mail: hiroyuki.fujita@qualedyn.com [Quality Electrodynamics, LCC, 777 Beta Dr, Cleveland, OH 44143-2336 (United States); Trattnig, Siegfried, E-mail: siegfried.trattnig@meduniwien.ac.at [Medical University of Vienna, Department of Radiology, Vienna General Hospital, Waeringer Guertel 18-20, A-1090 Vienna (Austria)

2012-08-15

The purpose of this study was to compare 3 T and 7 T signal-to-noise and contrast-to noise ratios of clinical sequences for imaging of the ankles with optimized sequences and dedicated coils. Ten healthy volunteers were examined consecutively on both systems with three clinical sequences: (1) 3D gradient-echo, T{sub 1}-weighted; (2) 2D fast spin-echo, PD-weighted; and (3) 2D spin-echo, T{sub 1}-weighted. SNR was calculated for six regions: cartilage; bone; muscle; synovial fluid; Achilles tendon; and Kager's fat-pad. CNR was obtained for cartilage/bone, cartilage/fluid, cartilage/muscle, and muscle/fat-pad, and compared by a one-way ANOVA test for repeated measures. Mean SNR significantly increased at 7 T compared to 3 T for 3D GRE, and 2D TSE was 60.9% and 86.7%, respectively. In contrast, an average SNR decrease of almost 25% was observed in the 2D SE sequence. A CNR increase was observed in 2D TSE images, and in most 3D GRE images. There was a substantial benefit from ultra high-field MR imaging of ankles with routine clinical sequences at 7 T compared to 3 T. Higher SNR and CNR at ultra-high field MR scanners may be useful in clinical practice for ankle imaging. However, carefully optimized protocols and dedicated extremity coils are necessary to obtain optimal results.

A HIPAA-compliant architecture for securing clinical images

Science.gov (United States)

Liu, Brent J.; Zhou, Zheng; Huang, H. K.

2005-04-01

The HIPAA (Health Insurance Portability and Accountability Act, Instituted April 2003) Security Standards mandate health institutions to protect health information against unauthorized use or disclosure. One approach to addressing this mandate is by utilizing user access control and generating audit trails of the various authorized as well as unauthorized user access of health data. Although most current clinical image systems (eg, PACS) have components that generate log files as a solution to address the HIPAA mandate, there is a lack of methodology to obtain and synthesize the pertinent data from the large volumes of log file data generated by these multiple components within a PACS. We have designed and developed a HIPAA Compliant Architecture specifically for tracking and auditing the image workflow of clinical imaging systems such as PACS. As an initial first step, a software toolkit was implemented based on the HIPAA Compliant architecture. The toolkit was implemented within a testbed PACS Simulator located in the Image Processing and Informatics (IPI) lab at the University of Southern California. Evaluation scenarios were developed where different user types performed legal and illegal access of PACS image data within each of the different components in the PACS Simulator. Results were based on whether the scenarios of unauthorized access were correctly identified and documented as well as normal operational activity.

Clinical evaluation of FMPSPGR sequence of the brain MR imaging

International Nuclear Information System (INIS)

Takahashi, Mitsuyuki; Hasegawa, Makoto; Mori, Naohiko; Yamanoguchi, Minoru; Matsubara, Tadashi

1998-01-01

In order to apply the FMPSPGR (fast multi planar spoiled GRASS) method to diagnose brain diseases, authors obtained the optimal condition for imaging by the phantom experiments and examined the clinical usefulness. Six kinds of the phantom, which were 4 of diluted Gd solution with different concentrations, olive oil and physiological saline solution were used. From the phantom experiments, TR/TE/FR=300/3.3/90 degrees was the optimal condition. The evaluation of the clinical images was performed on the same section by the ST method and the FMPSPGR method. Fifteen patients (9 men and 6 women, aged from 17 to 80 years) suspected of brain diseases were examined, including 8 of cerebral infarction, 1 of pontine infarction, 1 of brain contusion, 1 of intracerebral bleeding and 4 of brain tumors. Four cases of brain tumor were evaluated on the contrast imaging and the others were on the plain imaging. In the plain imaging, the FMPSPGR method was better than the SE method on the low signal region in the T1 weighted imaging. Furthermore, in the contrast imaging, it could give more clear images of the lesion in anterior cranial pit by suppressing artifacts of blood flow. The present results indicate that the FMPSPGR method is useful to diagnose brain diseases. (K.H.)

Imaging diagnosis in relapsing polychondritis and correlation with clinical and serological data

International Nuclear Information System (INIS)

Thaiss, W.M.; Nikolaou, K.; Horger, M.; Spengler, W.; Xenitidis, T.; Henes, J.; Spira, D.

2016-01-01

We hypothesize that imaging findings from CT and MRI correlate better with clinical markers for assessment of disease activity in patients with the rare relapsing polychondritis (RPC) than with serological inflammatory markers. Retrospective database search at our institution identified 28 patients (13 females; age 49.0 years ± 15.0 SD) with RP between September 2004 and March 2014. Institutional review board approval was obtained for this retrospective data analysis. All patients had clinically proven RPC with at least two episodes of active disease. Of those, 18 patients were examined with CT- and MRI and presented all morphologic features of RPC like bronchial/laryngeal/auricular cartilage thickness, contrast enhancement, increased T2-signal intensity. Imaging data was subsequently correlated with corresponding clinical symptoms like fever, dyspnea, stridor, uveitis, pain, hearing impairment as well as with acute-phase-inflammatory parameters like C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). The clinical parameters were in good agreement with imaging findings and clinical symptoms such as tracheal wall thickening and dyspnea (r =0.65 p = 0.05), joint synovitis on MRI and a higher McAdam score (r = 0.84 p < 0.001). No correlations were found between inflammatory laboratory markers, imaging findings and clinical features. Imaging diagnosis in RPC using CT and/or MRI delivers information about the degree of disease activity that correlates better with clinical features than unspecific inflammatory laboratory markers. Additionally, clinically unapparent cartilage involvement can be assessed adding value to the clinical diagnosis and therapy planning in this rare disease. (orig.)

Imaging diagnosis in relapsing polychondritis and correlation with clinical and serological data

Energy Technology Data Exchange (ETDEWEB)

Thaiss, W.M.; Nikolaou, K.; Horger, M. [Eberhard Karls University, Department of Radiology, Diagnostic and Interventional Radiology, Tuebingen (Germany); Spengler, W.; Xenitidis, T.; Henes, J. [Eberhard Karls University, Department of Internal Medicine II, Tuebingen (Germany); Spira, D. [Eberhard Karls University, Department of Radiology, Diagnostic and Interventional Radiology, Tuebingen (Germany); University Medical Center Heidelberg, Diagnostic and Interventional Radiology, Heidelberg (Germany)

2016-03-15

We hypothesize that imaging findings from CT and MRI correlate better with clinical markers for assessment of disease activity in patients with the rare relapsing polychondritis (RPC) than with serological inflammatory markers. Retrospective database search at our institution identified 28 patients (13 females; age 49.0 years ± 15.0 SD) with RP between September 2004 and March 2014. Institutional review board approval was obtained for this retrospective data analysis. All patients had clinically proven RPC with at least two episodes of active disease. Of those, 18 patients were examined with CT- and MRI and presented all morphologic features of RPC like bronchial/laryngeal/auricular cartilage thickness, contrast enhancement, increased T2-signal intensity. Imaging data was subsequently correlated with corresponding clinical symptoms like fever, dyspnea, stridor, uveitis, pain, hearing impairment as well as with acute-phase-inflammatory parameters like C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). The clinical parameters were in good agreement with imaging findings and clinical symptoms such as tracheal wall thickening and dyspnea (r =0.65 p = 0.05), joint synovitis on MRI and a higher McAdam score (r = 0.84 p < 0.001). No correlations were found between inflammatory laboratory markers, imaging findings and clinical features. Imaging diagnosis in RPC using CT and/or MRI delivers information about the degree of disease activity that correlates better with clinical features than unspecific inflammatory laboratory markers. Additionally, clinically unapparent cartilage involvement can be assessed adding value to the clinical diagnosis and therapy planning in this rare disease. (orig.)

Visual Perception Studies in CT images obtained lo low dose

International Nuclear Information System (INIS)

Adame Brooks, D.; Miller-Clemente, R. A.

2015-01-01

This paper has as aims to describe a strategy to evaluate the diagnostic quality of obtained images of method for dose reduction, with the purpose of determining the dose value or values from which the image quality is significantly degraded making it insufficient for the diagnostic. To complement and have an estimate of the quality of the images we established a group of measures of objective type, and the diagnostic quality of the images was evaluated through a group of observers using the analysis ROC and LROC. For ROC and LROC analyzes the behavior of the area under the curve in relation to the four proposed dose levels was obtained. For high dose levels, detection was good. The values of area under the curve decreased as the dose rate decreased, falling to values indicating low accuracy in diagnosis. This result indicates that the area under the curve decreases by the dose rate. We conclude that the objective quality measures selected are representative of the changes that occur in the resulting image and provided information on changes in the perception of observers. The experiments ROC and LROC allowed determine the range of dose values from which the image degradation causes a low accuracy in the diagnostic. (Author)

A high-resolution optical imaging system for obtaining the serial transverse section images of biologic tissue

Science.gov (United States)

Wu, Li; Zhang, Bin; Wu, Ping; Liu, Qian; Gong, Hui

2007-05-01

A high-resolution optical imaging system was designed and developed to obtain the serial transverse section images of the biologic tissue, such as the mouse brain, in which new knife-edge imaging technology, high-speed and high-sensitive line-scan CCD and linear air bearing stages were adopted and incorporated with an OLYMPUS microscope. The section images on the tip of the knife-edge were synchronously captured by the reflection imaging in the microscope while cutting the biologic tissue. The biologic tissue can be sectioned at interval of 250 nm with the same resolution of the transverse section images obtained in x and y plane. And the cutting job can be automatically finished based on the control program wrote specially in advance, so we save the mass labor of the registration of the vast images data. In addition, by using this system a larger sample can be cut than conventional ultramicrotome so as to avoid the loss of the tissue structure information because of splitting the tissue sample to meet the size request of the ultramicrotome.

Secondary electron images obtained with a standard photoelectron emission microscope set-up

International Nuclear Information System (INIS)

Benka, Oswald; Zeppenfeld, Peter

2005-01-01

The first results of secondary electron images excited by 3-4.3 keV electrons are presented. The images are obtained with a standard FOCUS-PEEM set-up equipped with an imaging energy filter (IEF). The electron gun was mounted on a standard PEEM entrance flange at an angle of 25 deg. with respect to the sample surface. A low extraction voltage of 500 V was used to minimize the deflection of the electron beam by the PEEM extraction electrode. The secondary electron images are compared to photoelectron images excited by a standard 4.9 eV UV lamp. In the case of a Cu pattern on a Si substrate it is found that the lateral resolution without the IEF is about the same for electron and photon excitation but that the relative electron emission intensities are very different. The use of the IEF reduces the lateral resolution. Images for secondary electron energies between eV 1 and eV 2 were obtained by setting the IEF to -V 1 and -V 2 ∼-(V 1 +5V) potentials and taking the difference of both images. Images up to 100 eV electron energies were recorded. The material contrast obtained in these difference images is discussed in terms of a secondary electron and photoelectron emission model and secondary electron energy spectra measured with a LEED-Auger spectrometer

Automated Registration of Multimodal Optic Disc Images: Clinical Assessment of Alignment Accuracy.

Science.gov (United States)

Ng, Wai Siene; Legg, Phil; Avadhanam, Venkat; Aye, Kyaw; Evans, Steffan H P; North, Rachel V; Marshall, Andrew D; Rosin, Paul; Morgan, James E

2016-04-01

To determine the accuracy of automated alignment algorithms for the registration of optic disc images obtained by 2 different modalities: fundus photography and scanning laser tomography. Images obtained with the Heidelberg Retina Tomograph II and paired photographic optic disc images of 135 eyes were analyzed. Three state-of-the-art automated registration techniques Regional Mutual Information, rigid Feature Neighbourhood Mutual Information (FNMI), and nonrigid FNMI (NRFNMI) were used to align these image pairs. Alignment of each composite picture was assessed on a 5-point grading scale: "Fail" (no alignment of vessels with no vessel contact), "Weak" (vessels have slight contact), "Good" (vessels with 50% contact), and "Excellent" (complete alignment). Custom software generated an image mosaic in which the modalities were interleaved as a series of alternate 5×5-pixel blocks. These were graded independently by 3 clinically experienced observers. A total of 810 image pairs were assessed. All 3 registration techniques achieved a score of "Good" or better in >95% of the image sets. NRFNMI had the highest percentage of "Excellent" (mean: 99.6%; range, 95.2% to 99.6%), followed by Regional Mutual Information (mean: 81.6%; range, 86.3% to 78.5%) and FNMI (mean: 73.1%; range, 85.2% to 54.4%). Automated registration of optic disc images by different modalities is a feasible option for clinical application. All 3 methods provided useful levels of alignment, but the NRFNMI technique consistently outperformed the others and is recommended as a practical approach to the automated registration of multimodal disc images.

A data grid for imaging-based clinical trials

Science.gov (United States)

Zhou, Zheng; Chao, Sander S.; Lee, Jasper; Liu, Brent; Documet, Jorge; Huang, H. K.

2007-03-01

Clinical trials play a crucial role in testing new drugs or devices in modern medicine. Medical imaging has also become an important tool in clinical trials because images provide a unique and fast diagnosis with visual observation and quantitative assessment. A typical imaging-based clinical trial consists of: 1) A well-defined rigorous clinical trial protocol, 2) a radiology core that has a quality control mechanism, a biostatistics component, and a server for storing and distributing data and analysis results; and 3) many field sites that generate and send image studies to the radiology core. As the number of clinical trials increases, it becomes a challenge for a radiology core servicing multiple trials to have a server robust enough to administrate and quickly distribute information to participating radiologists/clinicians worldwide. The Data Grid can satisfy the aforementioned requirements of imaging based clinical trials. In this paper, we present a Data Grid architecture for imaging-based clinical trials. A Data Grid prototype has been implemented in the Image Processing and Informatics (IPI) Laboratory at the University of Southern California to test and evaluate performance in storing trial images and analysis results for a clinical trial. The implementation methodology and evaluation protocol of the Data Grid are presented.

Optimization of three-dimensional angiographic data obtained by self-calibration of multiview imaging

International Nuclear Information System (INIS)

Noeel, Peter B.; Hoffmann, Kenneth R.; Kasodekar, Snehal; Walczak, Alan M.; Schafer, Sebastian

2006-01-01

Stroke is one of the leading causes of death in the U.S. The treatment of stroke often involves vascular interventions in which devices are guided to the intervention site often through tortuous vessels based on two-dimensional (2-D) angiographic images. Three dimensional (3-D) vascular information may facilitate these procedures. Methods have been proposed for the self-calibrating determination of 3-D vessel trees from biplane and multiple plane images and the geometric relationships between the views (imaging geometries). For the biplane analysis, four or more corresponding points must be identified in the biplane images. For the multiple view technique, multiple vessels must be indicated and only the translation vectors relating the geometries are calculated. We have developed methods for the calculation of the 3-D vessel data and the full transformations relating the multiple views (rotations and translations) obtained during interventional procedures, and the technique does not require indication of corresponding points, but only the indication of a single vessel, e.g., the vessel of interest. Multiple projection views of vessel trees are obtained and transferred to the analysis computer. The vessel or vessels of interest are indicated by the user. Using the initial imaging geometry determined from the gantry information, 3-D vessel centerlines are calculated using the indicated centerlines in pairs of images. The imaging geometries are then iteratively adjusted and 3-D centerlines recalculated until the root-mean-square (rms) difference between the calculated 3-D centerlines is minimized. Simulations indicate that the 3-D centerlines can be accurately determined (to within 1 mm) even for errors in indication of the vessel endpoints as large as 5 mm. In phantom studies, the average rms difference between the pairwise calculated 3-D centerlines is approximately 7.5 mm prior to refinement (i.e., using the gantry information alone), whereas the average rms

Effects of acquisition time and reconstruction algorithm on image quality, quantitative parameters, and clinical interpretation of myocardial perfusion imaging

DEFF Research Database (Denmark)

Enevoldsen, Lotte H; Menashi, Changez A K; Andersen, Ulrik B

2013-01-01

time (HT) protocols and Evolution for Cardiac Software. METHODS: We studied 45 consecutive, non-selected patients referred for a clinically indicated routine 2-day stress/rest (99m)Tc-Sestamibi myocardial perfusion SPECT. All patients underwent an FT and an HT scan. Both FT and HT scans were processed......-RR) and for quantitative analysis (FT-FBP, HT-FBP, and HT-RR). The datasets were analyzed using commercially available QGS/QPS software and read by two observers evaluating image quality and clinical interpretation. Image quality was assessed on a 10-cm visual analog scale score. RESULTS: HT imaging was associated......: Use of RR reconstruction algorithms compensates for loss of image quality associated with reduced scan time. Both HT acquisition and RR reconstruction algorithm had significant effects on motion and perfusion parameters obtained with standard software, but these effects were relatively small...

Patient-specific quantification of image quality: An automated method for measuring spatial resolution in clinical CT images

Energy Technology Data Exchange (ETDEWEB)

Sanders, Jeremiah, E-mail: jeremiah.sanders@duke.edu [Medical Physics Graduate Program, Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Clinical Imaging Physics Group, Duke University, Durham, North Carolina 27710 (United States); Hurwitz, Lynne [Department of Radiology, Duke University, Durham, North Carolina 27710 (United States); Samei, Ehsan [Medical Physics Graduate Program, Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Clinical Imaging Physics Group, Duke University, Durham, North Carolina 27710 and Departments of Physics, Biomedical Engineering, Electrical and Computer Engineering, Duke University, Durham, North Carolina 27710 (United States)

2016-10-15

Purpose: To develop and validate an automated technique for evaluating the spatial resolution characteristics of clinical computed tomography (CT) images. Methods: Twenty one chest and abdominopelvic clinical CT datasets were examined in this study. An algorithm was developed to extract a CT resolution index (RI) analogous to the modulation transfer function from clinical CT images by measuring the edge-spread function (ESF) across the patient’s skin. A polygon mesh of the air-skin boundary was created. The faces of the mesh were then used to measure the ESF across the air-skin interface. The ESF was differentiated to obtain the line-spread function (LSF), and the LSF was Fourier transformed to obtain the RI. The algorithm’s ability to detect the radial dependence of the RI was investigated. RIs measured with the proposed method were compared with a conventional phantom-based method across two reconstruction algorithms (FBP and iterative) using the spatial frequency at 50% RI, f{sub 50}, as the metric for comparison. Three reconstruction kernels were investigated for each reconstruction algorithm. Finally, an observer study was conducted to determine if observers could visually perceive the differences in the measured blurriness of images reconstructed with a given reconstruction method. Results: RI measurements performed with the proposed technique exhibited the expected dependencies on the image reconstruction. The measured f{sub 50} values increased with harder kernels for both FBP and iterative reconstruction. Furthermore, the proposed algorithm was able to detect the radial dependence of the RI. Patient-specific measurements of the RI were comparable to the phantom-based technique, but the patient data exhibited a large spread in the measured f{sub 50}, indicating that some datasets were blurrier than others even when the projection data were reconstructed with the same reconstruction algorithm and kernel. Results from the observer study substantiated this

Limitations of airway dimension measurement on images obtained using multi-detector row computed tomography.

Directory of Open Access Journals (Sweden)

Tsuyoshi Oguma

Full Text Available OBJECTIVES: (a To assess the effects of computed tomography (CT scanners, scanning conditions, airway size, and phantom composition on airway dimension measurement and (b to investigate the limitations of accurate quantitative assessment of small airways using CT images. METHODS: An airway phantom, which was constructed using various types of material and with various tube sizes, was scanned using four CT scanner types under different conditions to calculate airway dimensions, luminal area (Ai, and the wall area percentage (WA%. To investigate the limitations of accurate airway dimension measurement, we then developed a second airway phantom with a thinner tube wall, and compared the clinical CT images of healthy subjects with the phantom images scanned using the same CT scanner. The study using clinical CT images was approved by the local ethics committee, and written informed consent was obtained from all subjects. Data were statistically analyzed using one-way ANOVA. RESULTS: Errors noted in airway dimension measurement were greater in the tube of small inner radius made of material with a high CT density and on images reconstructed by body algorithm (p<0.001, and there was some variation in error among CT scanners under different fields of view. Airway wall thickness had the maximum effect on the accuracy of measurements with all CT scanners under all scanning conditions, and the magnitude of errors for WA% and Ai varied depending on wall thickness when airways of <1.0-mm wall thickness were measured. CONCLUSIONS: The parameters of airway dimensions measured were affected by airway size, reconstruction algorithm, composition of the airway phantom, and CT scanner types. In dimension measurement of small airways with wall thickness of <1.0 mm, the accuracy of measurement according to quantitative CT parameters can decrease as the walls become thinner.

Improvements in the management of rheumatic patients from vertebral image obtained through dual-energy X-ray absorptiometry

Directory of Open Access Journals (Sweden)

D. Gatti

2011-09-01

Full Text Available The diagnosis of asymptomatic vertebral fracture is clinically useful and the identification of new fractures may influences the choice of appropriate therapeutic measures. In order to identify moderate and asymptomatic vertebral deformities in an objective and reproducible manner, vertebral morphometry is performed. This method measures the vertebral body’s anterior, middle and posterior heights at the dorsal and lumbar level. Currently this technique is performed on lateral images of the spine obtained through the traditional X-ray method (radiological morphometry or morphometric X-ray radiography, MRX and, more recently from images obtained through dual-energy X-ray absorptiometry (DXA machines (visual assessment of x-ray absoptiometry scans or morphometric X-ray absorptiometry, MXA, commonly used to measure bone mineral density. The main advantage of MXA relative to MRX is the lower radiation dose to which the patient is exposed during the exam. In addition, MXA scans offers the advantage of acquiring a single image of thoracic and lumbar spine, without any distortion (e.g.: coning. The most obvious advantage of MXA is the opportunity of obtaining during the same session a bone mineral density evaluation, and digital images that are easily processable, manageable, recordable and comparable for the patient’s follow up. A limitation of the MXA technique is the inferior quality of the images, that make often impossible the detection of the vertebral edges, and the impossibility to visualize the upper thoracic vertebral bodies. MXA, despite its intrinsic limitations, when carried out by trained personnel may provide substantial improvements in the management (diagnosis and follow-up of rheumatic patients.

Curved crystal x-ray optics for monochromatic imaging with a clinical source.

Science.gov (United States)

Bingölbali, Ayhan; MacDonald, C A

2009-04-01

Monochromatic x-ray imaging has been shown to increase contrast and reduce dose relative to conventional broadband imaging. However, clinical sources with very narrow energy bandwidth tend to have limited intensity and field of view. In this study, focused fan beam monochromatic radiation was obtained using doubly curved monochromator crystals. While these optics have been in use for microanalysis at synchrotron facilities for some time, this work is the first investigation of the potential application of curved crystal optics to clinical sources for medical imaging. The optics could be used with a variety of clinical sources for monochromatic slot scan imaging. The intensity was assessed and the resolution of the focused beam was measured using a knife-edge technique. A simulation model was developed and comparisons to the measured resolution were performed to verify the accuracy of the simulation to predict resolution for different conventional sources. A simple geometrical calculation was also developed. The measured, simulated, and calculated resolutions agreed well. Adequate resolution and intensity for mammography were predicted for appropriate source/optic combinations.

Clinical blood pool MR Imaging

Energy Technology Data Exchange (ETDEWEB)

Leiner, Tim [Maastrich University Medical Center (Netherlands). Dept. of Radiology; Goyen, Martin [University Medical Center Hamburg-Eppendorf (Germany); Rohrer, Mathias [Bayer Schering Pharma AG, Berlin (Germany). European Business Unit Diagnostic Imaging; Schoenberg, Stefan O. (eds.) [University Hospital Mannheim Medical Faculty Mannheim - Heidelberg Univ. (Germany). Dept. of Clinical Radiology and Nuclear Medicine

2008-07-01

Clinical Blood Pool MR Imaging - This excellent treatise on Vasovist {sup registered} created by a team of exceptional faculty who are pioneers in MR Angiography covers the basic techniques, safety, efficacy, image processing and pharmaco-economic details to successfully implement a new level of MRA image quality with this new contrast agent. Martin Prince, Cornell University, New York The editors and authors have made groundbreaking contributions towards establishing MR angiography in various investigative settings, rendering it more precise and applying it for diverse indications. The work presented here is founded upon the extensive experience of the editors, as well as the broad range of experience from other scientific working groups. Maximilian Reiser, Ludwig Maximilian University, Munich Vasovist {sup registered} (Gadofosveset), worldwide the first blood pool agent, has only recently become available for clinical use, but has already gained wide acceptance as a tool to improve magnetic resonance angiography. This book presents the first in-depth introduction to the basic physicochemical aspects of the agent, the application of Vasovist {sup registered} in clinical MRA, as well as potential clinical applications beyond MRA and patient management-related aspects. The first part of the book explains basic and technical properties of the agent and the differences of Vasovist {sup registered} compared to currently available extracellular agents. The second part contains detailed chapters on safety and efficacy. In the third part the focus is on MR angiographic applications, and in the fourth part of the book potential clinical fields beyond MRA are explored. All clinical chapters feature ready-to-use clinical protocols and a series of take home messages that concisely summarize the current role of blood pool imaging for each specific indication. (orig.)

Techniques for combining isotopic images obtained at different energies

International Nuclear Information System (INIS)

Soussaline, F.; Di Paola, R.; Bazin, J.P.

1976-01-01

The technique described should be considered as a first step towards the classification of scintigraphic data where the energy is included. As in all such studies the interpretation of the resulting images is not necessarily at first evident, and certain experience needs to be established. This applies in particular to the images obtained with the higher factors. It is possible that the use of this technique may resolve, without requiring a priori information, the problem previously encountered using the other 'subtraction' type techniques [fr

A simple methodology for obtaining X-ray color images in scanning electron microscopy

International Nuclear Information System (INIS)

Veiga, M.M. da; Pietroluongo, L.R.V.

1985-01-01

A simple methodology for obtaining at least 3 elements X-ray images in only one photography is described. The fluorescent X-ray image is obtained from scanning electron microscopy with energy dispersion analysis system. The change of detector analytic channels, color cellophane foils and color films are used sequentially. (M.C.K.) [pt

Usefulness and limitation of functional MRI with echo planar imaging using clinical MR apparatus

International Nuclear Information System (INIS)

Kusunoki, Katsusuke; Zenke, Kiichiro; Saito, Masahiro; Sadamoto, Kazuhiko; Ohue, Shiro; Sakaki, Saburo; Kumon, Yoshiaki; Kabasawa, Hiroyuki; Nagasawa, Kiyoshi

1998-01-01

We studied blood oxygen level-dependent (BOLD) functional MRI (fMRI) with EPI sequence in 21 normal volunteers and 8 presurgical clinical patients using a 1.5 T clinical MRI apparatus. To optimize the imaging parameters, we compared the fMRI images obtained by GFE-EPI and by SE-EPI in normal volunteers while each squeezed a sponge ball. We identified the motor cortex in 85.7% of normal volunteers by GFE-EPI in contrast to only 28.6% by SE-EPI. In addition, our clinical MR apparatus, using optimized parameters, maximally provides 15 slices per 5 seconds. In patients with brain tumor close to the sensorimotor cortex, we attempted to identify the motor cortex preoperatively by this procedure and found a significant increase of signal intensity in the motor cortex in 5 of 8 patients. In conclusion, fMRI using EPI may be useful for identifying the motor cortex preoperatively. However, further development of the apparatus is needed to obtain better temporal and spatial resolution for clinical applications. (author)

Diagnostic value of sectional images obtained by emission tomography

International Nuclear Information System (INIS)

Roucayrol, J.C.

1981-01-01

It is now possible to obtain clear images of the various planes in and around a structure with ultra-sounds (echotomography), X-rays (computerized tomography) and recently, gamma-rays from radioactive substances (emission tomography). Axial transverse tomography, which is described here, is to conventional scintigraphy what CT scan is to radiography. It provides images of any structure capable of concentrating sufficiently a radioactive substance administered intravenously. These images are perpendicular to the longitudinal axis of the body. As shown by examples in the liver, lungs and myocardium, lesions which had passed unnoticed with other exploratory techniques can now be demonstrated, and the location, shape and extension of known lesions can be more accurately assessed. Emission tomography already has its place in modern diagnostic procedures side by side with echotomography and CT scan [fr

A review of molecular imaging studies reaching the clinical stage

International Nuclear Information System (INIS)

Wong, Franklin C.; Kim, E. Edmund

2009-01-01

The practice of molecular imaging in the clinics is examined across various imaging modalities to assess the current status of clinical molecular imaging. The various physiologic and scientific bases of clinical molecular imaging are surveyed to assess the possibilities and opportunities for the deployment of the different imaging modalities in the near future. The requisites for successful candidate(s) of clinical molecular imaging are reviewed for future development.

DETERMINING SPECTRAL REFLECTANCE COEFFICIENTS FROM HYPERSPECTRAL IMAGES OBTAINED FROM LOW ALTITUDES

Directory of Open Access Journals (Sweden)

P. Walczykowski

2016-06-01

Full Text Available Remote Sensing plays very important role in many different study fields, like hydrology, crop management, environmental and ecosystem studies. For all mentioned areas of interest different remote sensing and image processing techniques, such as: image classification (object and pixel- based, object identification, change detection, etc. can be applied. Most of this techniques use spectral reflectance coefficients as the basis for the identification and distinction of different objects and materials, e.g. monitoring of vegetation stress, identification of water pollutants, yield identification, etc. Spectral characteristics are usually acquired using discrete methods such as spectrometric measurements in both laboratory and field conditions. Such measurements however can be very time consuming, which has led many international researchers to investigate the reliability and accuracy of using image-based methods. According to published and ongoing studies, in order to acquire these spectral characteristics from images, it is necessary to have hyperspectral data. The presented article describes a series of experiments conducted using the push-broom Headwall MicroHyperspec A-series VNIR. This hyperspectral scanner allows for registration of images with more than 300 spectral channels with a 1.9 nm spectral bandwidth in the 380- 1000 nm range. The aim of these experiments was to establish a methodology for acquiring spectral reflectance characteristics of different forms of land cover using such sensor. All research work was conducted in controlled conditions from low altitudes. Hyperspectral images obtained with this specific type of sensor requires a unique approach in terms of post-processing, especially radiometric correction. Large amounts of acquired imagery data allowed the authors to establish a new post- processing approach. The developed methodology allowed the authors to obtain spectral reflectance coefficients from a hyperspectral sensor

Determining Spectral Reflectance Coefficients from Hyperspectral Images Obtained from Low Altitudes

Science.gov (United States)

Walczykowski, P.; Jenerowicz, A.; Orych, A.; Siok, K.

2016-06-01

Remote Sensing plays very important role in many different study fields, like hydrology, crop management, environmental and ecosystem studies. For all mentioned areas of interest different remote sensing and image processing techniques, such as: image classification (object and pixel- based), object identification, change detection, etc. can be applied. Most of this techniques use spectral reflectance coefficients as the basis for the identification and distinction of different objects and materials, e.g. monitoring of vegetation stress, identification of water pollutants, yield identification, etc. Spectral characteristics are usually acquired using discrete methods such as spectrometric measurements in both laboratory and field conditions. Such measurements however can be very time consuming, which has led many international researchers to investigate the reliability and accuracy of using image-based methods. According to published and ongoing studies, in order to acquire these spectral characteristics from images, it is necessary to have hyperspectral data. The presented article describes a series of experiments conducted using the push-broom Headwall MicroHyperspec A-series VNIR. This hyperspectral scanner allows for registration of images with more than 300 spectral channels with a 1.9 nm spectral bandwidth in the 380- 1000 nm range. The aim of these experiments was to establish a methodology for acquiring spectral reflectance characteristics of different forms of land cover using such sensor. All research work was conducted in controlled conditions from low altitudes. Hyperspectral images obtained with this specific type of sensor requires a unique approach in terms of post-processing, especially radiometric correction. Large amounts of acquired imagery data allowed the authors to establish a new post- processing approach. The developed methodology allowed the authors to obtain spectral reflectance coefficients from a hyperspectral sensor mounted on an

Processing method of images obtained during the TESIS/CORONAS-PHOTON experiment

Science.gov (United States)

Kuzin, S. V.; Shestov, S. V.; Bogachev, S. A.; Pertsov, A. A.; Ulyanov, A. S.; Reva, A. A.

2011-04-01

In January 2009, the CORONAS-PHOTON spacecraft was successfully launched. It includes a set of telescopes and spectroheliometers—TESIS—designed to image the solar corona in soft X-ray and EUV spectral ranges. Due to features of the reading system, to obtain physical information from these images, it is necessary to preprocess them, i.e., to remove the background, correct the white field, level, and clean. The paper discusses the algorithms and software developed and used for the preprocessing of images.

Ultrasound Image Quality Assessment: A framework for evaluation of clinical image quality

DEFF Research Database (Denmark)

Hemmsen, Martin Christian; Pedersen, Mads Møller; Nikolov, Svetoslav Ivanov

2010-01-01

Improvement of ultrasound images should be guided by their diagnostic value. Evaluation of clinical image quality is generally performed subjectively, because objective criteria have not yet been fully developed and accepted for the evaluation of clinical image quality. Based on recommendation 50...... information, which is fast enough to get sufficient number of scans under realistic operating conditions, so that statistical evaluation is valid and reliable....

Clinical introduction of image lag correction for a cone beam CT system

International Nuclear Information System (INIS)

Stankovic, Uros; Ploeger, Lennert S.; Sonke, Jan-Jakob; Herk, Marcel van

2016-01-01

Purpose: Image lag in the flat-panel detector used for Linac integrated cone beam computed tomography (CBCT) has a degrading effect on CBCT image quality. The most prominent visible artifact is the presence of bright semicircular structure in the transverse view of the scans, known also as radar artifact. Several correction strategies have been proposed, but until now the clinical introduction of such corrections remains unreported. In November 2013, the authors have clinically implemented a previously proposed image lag correction on all of their machines at their main site in Amsterdam. The purpose of this study was to retrospectively evaluate the effect of the correction on the quality of CBCT images and evaluate the required calibration frequency. Methods: Image lag was measured in five clinical CBCT systems (Elekta Synergy 4.6) using an in-house developed beam interrupting device that stops the x-ray beam midway through the data acquisition of an unattenuated beam for calibration. A triple exponential falling edge response was fitted to the measured data and used to correct image lag from projection images with an infinite response. This filter, including an extrapolation for saturated pixels, was incorporated in the authors’ in-house developed clinical CBCT reconstruction software. To investigate the short-term stability of the lag and associated parameters, a series of five image lag measurement over a period of three months was performed. For quantitative analysis, the authors have retrospectively selected ten patients treated in the pelvic region. The apparent contrast was quantified in polar coordinates for scans reconstructed using the parameters obtained from different dates with and without saturation handling. Results: Visually, the radar artifact was minimal in scans reconstructed using image lag correction especially when saturation handling was used. In patient imaging, there was a significant reduction of the apparent contrast from 43 ± 16.7 to

Clinical introduction of image lag correction for a cone beam CT system.

Science.gov (United States)

Stankovic, Uros; Ploeger, Lennert S; Sonke, Jan-Jakob; van Herk, Marcel

2016-03-01

Image lag in the flat-panel detector used for Linac integrated cone beam computed tomography (CBCT) has a degrading effect on CBCT image quality. The most prominent visible artifact is the presence of bright semicircular structure in the transverse view of the scans, known also as radar artifact. Several correction strategies have been proposed, but until now the clinical introduction of such corrections remains unreported. In November 2013, the authors have clinically implemented a previously proposed image lag correction on all of their machines at their main site in Amsterdam. The purpose of this study was to retrospectively evaluate the effect of the correction on the quality of CBCT images and evaluate the required calibration frequency. Image lag was measured in five clinical CBCT systems (Elekta Synergy 4.6) using an in-house developed beam interrupting device that stops the x-ray beam midway through the data acquisition of an unattenuated beam for calibration. A triple exponential falling edge response was fitted to the measured data and used to correct image lag from projection images with an infinite response. This filter, including an extrapolation for saturated pixels, was incorporated in the authors' in-house developed clinical cbct reconstruction software. To investigate the short-term stability of the lag and associated parameters, a series of five image lag measurement over a period of three months was performed. For quantitative analysis, the authors have retrospectively selected ten patients treated in the pelvic region. The apparent contrast was quantified in polar coordinates for scans reconstructed using the parameters obtained from different dates with and without saturation handling. Visually, the radar artifact was minimal in scans reconstructed using image lag correction especially when saturation handling was used. In patient imaging, there was a significant reduction of the apparent contrast from 43 ± 16.7 to 15.5 ± 11.9 HU without the

Relationship between clinical findings of temporomandibular disorders and magnetic resonance imaging

International Nuclear Information System (INIS)

Iizuka, Yasuyuki; Miura, Hiroyuki; Ishikawa, Fujiro; Kikuchi, Shiori; Konishi, Nobuhiro; Sakamaki, Kimio

1996-01-01

The present study was conducted to investigate the relationship between magnetic resonance imaging (MRI) of the temporomandibular joint (TMJ) and clinical findings of patients having symptoms of temporomandibular disorders, and to consider the possibility to grasp the internal derangement of the TMJ from clinical findings. Subjects were 80 patients who visited to ask orthodontic treatment 16 males and 64 females. The average age was 22 years and 4 months. We performed a investigation of both their previous and present illness. In addition, to decide the correct condition concerning the internal derangement of the TMJ, patients were given MRI examinations (G. E. medical system Signa 1.5 Tesla) before orthodontic treatment. Results were as follows: The three symptoms of temporomandibular disorders-noise, pain, and abnormal mandibular movement, were not related to constant disk displacement. It seemed difficult to infer and obtain the diagnosis of the condition of internal derangement of the TMJ only from clinical findings. In a dental clinics having no medical imaging instrument such as MRI, it was, however, considered that the following items will make it possible to define the condition of internal derangements of the TMJ from clinical findings. As to respects concerning clinical findings, it is necessary to consider the previous illness as well as present illness. TMJ noise indicates a higher relationship to the disk displacement in MRI findings. The temporomandibular joint with plural symptoms indicated a higher incidence of disk displacement examined by MR Imaging than that with a single symptom. (author)

Diagnostic imaging capabilities of the Ocelot -Optical Coherence Tomography System, ex-vivo evaluation and clinical relevance

International Nuclear Information System (INIS)

Dohad, Suhail; Shao, John; Cawich, Ian; Kankaria, Manish; Desai, Arjun

2015-01-01

Optical coherence tomography (OCT) is a high-resolution sub-surface imaging modality using near-infrared light to provide accurate and high contrast intra-vascular images. This enables accurate assessment of diseased arteries before and after intravascular intervention. This study was designed to corroborate diagnostic imaging equivalence between the Ocelot and the Dragonfly OCT systems with regards to the intravascular features that are most important in clinical management of patients with atherosclerotic vascular disease. These intravascular features were then corroborated in vivo during treatment of peripheral arterial disease (PAD) pathology using the Ocelot catheter. In order to compare the diagnostic information obtained by Ocelot (Avinger Inc., Redwood City, CA) and Dragonfly (St. Jude Medical, Minneapolis, MN) OCT systems, we utilized ex-vivo preparations of arterial segments. Ocelot and Dragonfly catheters were inserted into identical cadaveric femoral peripheral arteries for image acquisition and interpretation. Three independent physician interpreters assessed the images to establish accuracy and sensitivity of the diagnostic information. Histologic evaluation of the corresponding arterial segments provided the gold standard for image interpretation. In vivo clinical images were obtained during therapeutic interventions that included crossing of peripheral chronic total occlusions (CTOs) using the Ocelot catheter. Strong concordance was demonstrated when matching image characteristics between both OCT systems and histology. The Dragonfly and Ocelot system’s vessel features were interpreted with high sensitivity (91.1–100 %) and specificity (86.7–100 %). Inter-observer concordance was documented with excellent correlation across all vessel features. The clinical benefit that the Ocelot OCT system provided was demonstrated by comparable procedural images acquired at the point of therapy. The study demonstrates equivalence of image acquisition and

MAGNETIC-RESONANCE-IMAGING USING A CLINICAL WHOLE-BODY SYSTEM - AN INTRODUCTION TO A USEFUL TECHNIQUE IN SMALL ANIMAL-EXPERIMENTS

NARCIS (Netherlands)

WOLF, RFE; LAM, KH; MOOYAART, EL; BLEICHRODT, RP; NIEUWENHUIS, P; SCHAKENRAAD, JM

A clinical whole body magnetic resonance imaging (MRI) system with high resolution coils was used to obtain non-invasive images of the living rat. The results demonstrate the feasibility of the set-up and the advantages of this new imaging technique: detailed information, no extra costs,

Dynamic 99mTc-MAG3 renography: images for quality control obtained by combining pharmacokinetic modelling, an anthropomorphic computer phantom and Monte Carlo simulated scintillation camera imaging

Science.gov (United States)

Brolin, Gustav; Sjögreen Gleisner, Katarina; Ljungberg, Michael

2013-05-01

In dynamic renal scintigraphy, the main interest is the radiopharmaceutical redistribution as a function of time. Quality control (QC) of renal procedures often relies on phantom experiments to compare image-based results with the measurement setup. A phantom with a realistic anatomy and time-varying activity distribution is therefore desirable. This work describes a pharmacokinetic (PK) compartment model for 99mTc-MAG3, used for defining a dynamic whole-body activity distribution within a digital phantom (XCAT) for accurate Monte Carlo (MC)-based images for QC. Each phantom structure is assigned a time-activity curve provided by the PK model, employing parameter values consistent with MAG3 pharmacokinetics. This approach ensures that the total amount of tracer in the phantom is preserved between time points, and it allows for modifications of the pharmacokinetics in a controlled fashion. By adjusting parameter values in the PK model, different clinically realistic scenarios can be mimicked, regarding, e.g., the relative renal uptake and renal transit time. Using the MC code SIMIND, a complete set of renography images including effects of photon attenuation, scattering, limited spatial resolution and noise, are simulated. The obtained image data can be used to evaluate quantitative techniques and computer software in clinical renography.

TRANSFORMATION ALGORITHM FOR IMAGES OBTAINED BY OMNIDIRECTIONAL CAMERAS

Directory of Open Access Journals (Sweden)

V. P. Lazarenko

2015-01-01

Full Text Available Omnidirectional optoelectronic systems find their application in areas where a wide viewing angle is critical. However, omnidirectional optoelectronic systems have a large distortion that makes their application more difficult. The paper compares the projection functions of traditional perspective lenses and omnidirectional wide angle fish-eye lenses with a viewing angle not less than 180°. This comparison proves that distortion models of omnidirectional cameras cannot be described as a deviation from the classic model of pinhole camera. To solve this problem, an algorithm for transforming omnidirectional images has been developed. The paper provides a brief comparison of the four calibration methods available in open source toolkits for omnidirectional optoelectronic systems. Geometrical projection model is given used for calibration of omnidirectional optical system. The algorithm consists of three basic steps. At the first step, we calculate he field of view of a virtual pinhole PTZ camera. This field of view is characterized by an array of 3D points in the object space. At the second step the array of corresponding pixels for these three-dimensional points is calculated. Then we make a calculation of the projection function that expresses the relation between a given 3D point in the object space and a corresponding pixel point. In this paper we use calibration procedure providing the projection function for calibrated instance of the camera. At the last step final image is formed pixel-by-pixel from the original omnidirectional image using calculated array of 3D points and projection function. The developed algorithm gives the possibility for obtaining an image for a part of the field of view of an omnidirectional optoelectronic system with the corrected distortion from the original omnidirectional image. The algorithm is designed for operation with the omnidirectional optoelectronic systems with both catadioptric and fish-eye lenses

[Microdose clinical trial--impact of PET molecular imaging].

Science.gov (United States)

Yano, Tsuneo; Watanabe, Yasuyoshi

2010-10-01

Microdose (MD) clinical trial and exploratory IND study including sub-therapeutic dose and therapeutic dose which are higher than microdoses are expected to bring about innovations in drug development. The outlines of guidances for microdose clinical trial and ICH-M3 (R2) issued by the MHLW in June, 2008, and February, 2010, are first explained, respectively, and some examples of their application to clinical developments of therapeutic drugs in the infection and cancer fields are introduced. Especially, thanks to the progress of molecular imaging research, a new field of drug development is explored by using imaging biomarkers for efficacy or safety evaluation which visualize biomarkers by PET imaging agents. Finally, the roadmap for drug development in infection and cancer fields utilizing PET molecular imaging is discussed.

Clinical efficiency, image quality and dosimetric considerations

Energy Technology Data Exchange (ETDEWEB)

Arreola, M. [Director of Clinical Radiological Physics, Shands Hospital at the University of Florida College of Medicine, Gainesville, FL (United States)

2000-07-01

Three decades have passed since the first clinical use of the famous EMI Computed Axial Tomography (Cat) scanner. At the time, the prospects for clinical success of this innovative idea were not very good. Time, however, has proven otherwise as what is now simply known as Computed tomography (CT) has been boosted in each one of these decades for different reasons. In the 1970s, technological progress augmented by the realization of the importance of tomographic imaging got everything started; in the 1980s, the boom in health care demand in the US solidified its position and in the 1990s the technological explosion in computers and the imperative need to lower costs in the health care industry have prompted the most dramatic changes in the wy CT is utilized in the year 2000. Thus, different motivations have led the way of progress in CT at various times, and in spite of amazing developments in other crucial imaging modalities, such as ultrasound, Doppler ultrasound, digital subtraction angiography and magnetic resonance imaging, CT maintains its rightful place as the premiere imaging modality in the modern radiology department. This work covers the basic principles of tomographic image reconstruction, and how axial CT scanners progressed historically in the first two decades. Developments in X-ray tubes, and detection systems are highlighted, as well as the impact of clinical efficiency, image quality and patient doses. The basic construction of translate-rotate (1st and 2nd generation), rotate-rotate (3rd generation) and detector ring (4th generation) scanners are described. The so-called 5th generation scanner, the electron beam scanner, is also described, with its clinical and technical advantages and its inherent financial and maintenance disadvantages, which brought the advent of spiral and multi-slice scanners. These most recent developments in CT technology have opened a new era in the clinical use of CT; and although image quality has reached an expected

Clinical efficiency, image quality and dosimetric considerations

International Nuclear Information System (INIS)

Arreola, M.

2000-01-01

Three decades have passed since the first clinical use of the famous EMI Computed Axial Tomography (Cat) scanner. At the time, the prospects for clinical success of this innovative idea were not very good. Time, however, has proven otherwise as what is now simply known as Computed tomography (CT) has been boosted in each one of these decades for different reasons. In the 1970s, technological progress augmented by the realization of the importance of tomographic imaging got everything started; in the 1980s, the boom in health care demand in the US solidified its position and in the 1990s the technological explosion in computers and the imperative need to lower costs in the health care industry have prompted the most dramatic changes in the wy CT is utilized in the year 2000. Thus, different motivations have led the way of progress in CT at various times, and in spite of amazing developments in other crucial imaging modalities, such as ultrasound, Doppler ultrasound, digital subtraction angiography and magnetic resonance imaging, CT maintains its rightful place as the premiere imaging modality in the modern radiology department. This work covers the basic principles of tomographic image reconstruction, and how axial CT scanners progressed historically in the first two decades. Developments in X-ray tubes, and detection systems are highlighted, as well as the impact of clinical efficiency, image quality and patient doses. The basic construction of translate-rotate (1st and 2nd generation, rotate-rotate (3rd generation) and detector ring (4th generation) scanners are described. The so-called 5th generation scanner, the electron beam scanner, is also described, with its clinical and technical advantages and its inherent financial and maintenance disadvantages, which brought the advent of spiral and multi-slice scanners. These most recent developments in CT technology have opened a new era in the clinical use of CT; and although image quality has reached an expected

Clinical PET/MR Imaging in Oncology

DEFF Research Database (Denmark)

Kjær, Andreas; Torigian, Drew A.

2016-01-01

. The question, therefore, arises regarding what the future clinical applications of PET/MR imaging will be. In this article, the authors discuss ways in which PET/MR imaging may be used in future applications that justify the added cost, predominantly focusing on oncologic applications. The authors suggest...

Clinical evaluation of gadodiamide injection in paediatric MR imaging

International Nuclear Information System (INIS)

Hanquinet, S.; Christophe, C.; Greef, D. de; Gordon, P.; Perlmutter, N.

1996-01-01

The safety and efficacy of intravenous gadodiamide injection, 0.1 mmol/kg body weight, have been evaluated in an open label, non-comparative as to drug, phase III clinical trial in 50 children from 6 months to 13 years of age, referred for MRI requiring the injection of a contrast medium. The central nervous system and other body areas were examined with T1 sequences before and after intravenous injection of the contrast medium. Overall safety was very good and no clinically relevant changes were evident as regards heart rate and venous blood oxygen saturation after injection. No adverse event or discomfort was experienced by conscious patients that could with certainty be related to the contrast medium, but slight movements were observed in two sedated patients that could be related to the injection. Comparing pre- and post-injection images, additional diagnostic information could be obtained from the latter in 41 patients (82 %). In these images, the number of lesions detected increased and they were generally better delineated and their size more easily estimated. The results of this trial indicate that gadodiamide injection is safe and effective for MRI examinations in children. (orig.). With 3 figs., 1 tab

Clinical and imaging findings in spinal cord arteriovenous malformations

International Nuclear Information System (INIS)

Kim, Sang Heum; Kim, Dong Ik; Yoon, Pyeong Ho; Jeon, Pyoung; Ihn, Yeon Kwon

1997-01-01

The purpose of this study is to evaluate the findings of magnetic resonance (MR) imaging and selective spinal angiography of spinal cord arteriovenous malformations (SCAVMs) and to investigate the correlation of these findings with the development of clinical symptoms. In 16 patients diagnosed as suffering from SCAVMs, MR imaging and selective spinal angiograms were retrospectively analyzed and correlated with clinical symptoms. Clinical data were reviewed, especially concerning the mode of onset of clinical symptoms, and MR images of SCAVMs were evaluated with regard to the following parameters: spinal cord swelling with T2 hyperintensity, cord atrophy, intramedullary hemorrhage, and contrast enhancement of the spinal cord. Selective spinal angiographic findings of SCAVMs were also evaluated in terms of the following , parameters: type of SCAVM, presence of aneurysms, and patterns of venous drainage. Imaging findings were also correlated with the development of clinical symptoms. Systematic evaluation of the findings of MR imaging and angiography provides detailed information on the type of AVM and status of the spinal cord parenchyma, and this can be correlated with clinical manifestations of SCAVM. In patients suffering from this condition, spinal cord dysfunction due to venous congestion appears to be the main cause of clinical symptoms. (author). 18 refs., 2 tabs., 3 figs

A simple solution for reducing artefacts due to conductive and dielectric effects in clinical magnetic resonance imaging at 3 T

International Nuclear Information System (INIS)

Sreenivas, M.; Lowry, M.; Gibbs, P.; Pickles, M.; Turnbull, L.W.

2007-01-01

The quality of imaging obtained at high magnetic field strengths can be degraded by various artefacts due to conductive and dielectric effects, which leads to loss of signal. Various methods have been described and used to improve the quality of the image affected by such artefacts. In this article, we describe the construction and use of a simple solution that can be used to diminish artefacts due to conductive and dielectric effects in clinical imaging at 3 T field strength and thereby improve the diagnostic quality of the images obtained

A simple solution for reducing artefacts due to conductive and dielectric effects in clinical magnetic resonance imaging at 3 T

Energy Technology Data Exchange (ETDEWEB)

Sreenivas, M. [Department of Radiology (Yorkshire Deanery-East), Hull Royal Infirmary, Anlaby Road, Hull HU3 2JZ (United Kingdom)]. E-mail: aprilsreenivas@hotmail.com; Lowry, M. [Centre for Magnetic Resonance Investigations, University of Hull, Hull Royal Infirmary, Anlaby Road, 1PR, Hull HU3 2JZ (United Kingdom); Gibbs, P. [Centre for Magnetic Resonance Investigations, University of Hull, Hull Royal Infirmary, Anlaby Road, 1PR, Hull HU3 2JZ (United Kingdom); Pickles, M. [Centre for Magnetic Resonance Investigations, University of Hull, Hull Royal Infirmary, Anlaby Road, 1PR, Hull HU3 2JZ (United Kingdom); Turnbull, L.W. [Centre for Magnetic Resonance Investigations, University of Hull, Hull Royal Infirmary, Anlaby Road, 1PR, Hull HU3 2JZ (United Kingdom)

2007-04-15

The quality of imaging obtained at high magnetic field strengths can be degraded by various artefacts due to conductive and dielectric effects, which leads to loss of signal. Various methods have been described and used to improve the quality of the image affected by such artefacts. In this article, we describe the construction and use of a simple solution that can be used to diminish artefacts due to conductive and dielectric effects in clinical imaging at 3 T field strength and thereby improve the diagnostic quality of the images obtained.

Effects of precompression on elasticity imaging of the breast: development of a clinically useful semiquantitative method of precompression assessment.

Science.gov (United States)

Barr, Richard G; Zhang, Zheng

2012-06-01

Elastography of the breast is a new technique for characterization of breast lesions. The reproducibility of elastographic techniques has been questioned. Precompression is known to effect elastographic results. This study determined the effect of precompression on clinical images and proposes a method to semiquantify the amount of precompression applied. Ten patients with different breast tissue types were evaluated with shear wave and strain elastography with varying amounts of precompression. The changes in the shear wave speed and images were documented. A semiquantitative method for determining the amount of precompression applied is presented. The reproducibility of the technique was determine by repeated measurements by 3 sonographers. Precompression substantially changes the elastographic results of patient images on both strain and shear wave elastography. Fat can have the same elasticity as cancer with clinically possible amounts of precompression. The proposed method for determining the amount of precompression applied has variability of less than 10%, which is within the error of the technique and would not affect clinical results. Four zones of precompression are identified, which are useful for explaining the effects of precompression on both strain and shear wave imaging. Precompression is a substantial factor in obtaining accurate results with elastography. A proposed simple, easily applied technique can be used to semiquantify the amount of precompression applied. Precompression should be minimized in obtaining breast clinical images.

Practical Approach for the Clinical Use of Dopamine Transporter Imaging

International Nuclear Information System (INIS)

Kim, Jae Seung

2008-01-01

Dopamine transporter imaging is useful in the diagnosis of Parkinson's disease and the most successful technique in the clinical use of neuroreceptor imaging. Recently, several radiopharmaceuticals including I-123 FP-CIT, Tc-99m TRODAT, and F-18 FP-CIT for dopamine transporter imaging have been approved for the routine clinical use in several European countries, Taiwan and Korea, respectively. This review summarized the practical issue for the routine clinical examination of dopamine transporter imaging

Studies on diagnosis of lung emphysema by CT image using experimental models and clinical cases

International Nuclear Information System (INIS)

Nakatani, Seiki

1998-01-01

Since the detailed report between the degree of functional disorder in lung emphysema and the analysis of CT image is quite unknown, the present study was attempted to produce the experimental model of lung emphysema with various stages by the administration of papain to the focal lobe in canine lung. Using this model or clinical lung emphysema, the relationship between the degree of destruction of alveolar walls, clinical pulmonary functions and CT images was investigated. CT scan was performed at the level of 50% vital capacity in both experimental models and clinical subjects by using spirometric gating CT. CT density histogram was obtained from CT image which was produced by using the developed software for this purpose. Densitometric parameters, such as mean CT value, %LAA, the peak in the histogram and 5% tile were selected from CT image. Papain solution of 5 mg/kg body weight was cumulatively administered to the left lower lobe in canine lung, resulting in the destruction of lung alveolar walls in parallel to the increasing dosage of papain. There was a significant correlation between not only the increasing dosage of papain, but also %FEV 1.0 and CT densitometric parameters, indicating that the histological changes of alveolar walls and the lung function in lung emphysema could be estimated by analysis of CT image. These experimental and clinical studies suggest that the analysis of CT image can reflect the pathophysiological changes in the lung and be useful for precise clinical diagnosis of lung emphysema. (author)

Nuclear medicine imaging in clinical practice: Current applications and future trends

International Nuclear Information System (INIS)

Galli, G.; Maini, C.L.

1985-01-01

The following conclusions can be drawn: 1) Even though developments in data digitalization enable also other imaging techniques to extract functional information, it is likely that nuclear medicine will keep and possibly increase its key role for functional studies requiring quantitative data analyses. This statement is true at present and it will probably remain true for a long time to come. 2) Nuclear medicine is and will remain an important clinical tool also for morphological or morphodynamic studies in selected situations. Of course the integration of nuclear medicine studies with other diagnostic procedures is highly desirable. The highest clinical yield of multi-test diagnostic protocols will be anyway obtained by the wisest physician as sophysticated technology is no substitution for intelligent clinical judgment. 3) The development of new radiopharmaceuticals with well characterized biokinetic features allowing precise tissue characterization opens new frontiers to be exploited by nuclear medicine centers equipped with conventional technology (digital gammacameras, SPECT). 4) Positron emission tomography is the most important new development of nuclear medicine imaging. Not only PET has already shown its enormous possibilities for physiological and pathophysiological studies, but the clinical relevance of selected applications has been proved. More experience is however needed to assess systematically the whole impact of PET studies in clinical practice and to perform dependable cost/benefit studies. 5) Among all other imaging techniques NMR is the closest to nuclear medicine because of a strict ''compatibility of aptitudes, training and methodology'' (4). Accordingly future improvements of both methods will be better achieved if they could be integrated and the results compared with the same institutions

The group study of diagnostic efficacy of cerebro-vascular disease by I-123 IMP SPECT images obtained with ring type SPECT scanner

International Nuclear Information System (INIS)

Machida, Kikuo; Honda, Norinari; Matsumoto, Toru

1991-01-01

We performed two image reading experiments in order to investigate the diagnostic capability of I-123 IMP SPECT obtained by the ring type SPECT scanner in cerebro-vascular disease. Fourteen physicians diagnosed SPECT images of 55 cases with reference to clinical neurological information, first without brain XCT images and second with XCT images. Each physician detected perfusion defects and redistributions of I-123 IMP and assigned a confidence level of abnormality for these SPECT findings by means of five rating method. From results obtained by ROC analysis, we concluded as follows. (1) Generally, I-123 IMP SPECT is a stable diagnostic modality in the diagnosis of cerebro-vascular disease and the image reading of XCT had no effects on the diagnosis of SPECT on the whole of physician. (2) However, there were unnegligible differences among individuals in the detectability of findings and the effect of XCT image reading. (3) Detectability of redistribution of I-123 IMP was lower than that of perfusion defect and inter-observer variation in the diagnostic performance for redistribution was larger than that of perfusion defect. The results suggest that it is necessary to standardize diagnostic criteria among physicians for redistribution of I-123 IMP. (author)

Clinical evaluation of {sup 99m}Tc-HMPAO labeled leukocyte imaging in ulcerative colitis

Energy Technology Data Exchange (ETDEWEB)

Saitoh, Yasuhiro; Aburano, Tamio; Takashio, Tetsuya; Shuke, Noriyuki; Ayabe, Tokiyoshi; Nomura, Masashi; Kohgo, Yutaka; Ishikawa, Yukio; Satoh, Junichi [Asahikawa Medical Coll., Hokkaido (Japan)

1996-07-01

Inflammatory imaging using {sup 99m}Tc-HMPAO-labeled mixed leukocytes was assessed for use in treating 11 cases diagnosed as ulcerative colitis: 10 cases with total colitis and 1 with left-sided colitis. They consisted of 8 patients with relapse-remitting type and 3 with chronic continuous type. Radionuclide abdominal images were obtained at 1 hr, 4 hr and 24 hr after intravenous injection of 200 MBq prepared {sup 99m}Tc leukocytes. Obvious colonic activity noted at 4 hr served as the basis for positive comparative criterion in the present study. The diagnostic efficacy of radionuclide imaging was compared with endoscopic findings (based on Matts` classification) and the clinical manifestations as reference. The sensitivity and specificity of this imaging were 83.3% and 85.7%, respectively, these values being consistent with endoscopic findings and clinical manifestations at sites of disease activity. All of positive images changed to negative after treatment by leukocyte apheresis or glucocorticoid. Based on these results, {sup 99m}Tc leukocyte imaging can be used to accurately evaluate severity and treatment response in ulcerative colitis. Leukocytes may be closely related to the pathogenesis of ulcerative colitis. (author)

3D images of paper obtained by phase-contrast X-ray microtomography: image quality and binarisation

International Nuclear Information System (INIS)

Antoine, Christine; Nygaard, Per; Gregersen, O.W.; Holmstad, Rune; Weitkamp, Timm; Rau, Christoph

2002-01-01

A series of paper samples was investigated using high-resolution phase-contrast microtomography at the beamline ID 22 of the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. It was shown that X-ray microtomography is a non-destructive method suitable for high resolution depicting real 3D-paper structures. The method detects highly localised changes in the refractive index of the sample, such as fibre-pore interfaces. The resulting tomograms represented an outlined image of the fibre structure with an image resolution of 1 μm. Analyses were performed in dry state, but in addition some were done in wet state. The raw data obtained were transformed into 3D images. The reconstructed slices were in general of rather good quality, even if both noise and ring-like artifacts were observed. These required special filtering efforts before a segmented binary volume could be obtained for further use of the data. This approach was made up of semi-automatic routines to convert the structure into a binary format. The resulting binary volumes can be used for further characterisation of the 3D-paper structure

Clinical advance in radionuclide imaging of pulmonary cancer

International Nuclear Information System (INIS)

Deng Zhiyong; Yang Lichun

2008-01-01

Radionuclide imaging of pulmonary cancer develops very rapidly in recent years. Its important value on the diagnosis, staging, monitoring recur and metastasis after treatment, and judging the curative effect and prognosis has been demonstrated. Clinicians pay more attention to it than before. This present article introduces the imaging principle, clinical use, good and bad points, progress situation of 67 Ga, 201 Tl, 99 Tc m , 18 F and their labelled compounds, which are more commonly used in clinical. And introduces the clinical progress of radionuclide imaging of pulmonary neoplasm concerning 99 Tc m -sestamibi ( 99 Tc m -MIBI), 99 Tc m -HL91 and 18 F-fluorodeoxyglucose ( 18 F-FDG) with emphasis. (authors)

Perinatal clinical and imaging features of CLOVES syndrome

Energy Technology Data Exchange (ETDEWEB)

Fernandez-Pineda, Israel [Virgen del Rocio Children' s Hospital, Department of Pediatric Surgery, Seville (Spain); Fajardo, Manuel [Virgen del Rocio Children' s Hospital, Department of Pediatric Radiology, Seville (Spain); Chaudry, Gulraiz; Alomari, Ahmad I. [Children' s Hospital Boston and Harvard Medical School, Division of Vascular and Interventional Radiology, Boston, MA (United States)

2010-08-15

We report a neonate with antenatal imaging features suggestive of CLOVES syndrome. Postnatal clinical and imaging findings confirmed the diagnosis, with the constellation of truncal overgrowth, cutaneous capillary malformation, lymphatic and musculoskeletal anomalies. The clinical, radiological and histopathological findings noted in this particular phenotype help differentiate it from other overgrowth syndromes with complex vascular anomalies. (orig.)

Magnetic resonance cardiac perfusion imaging-a clinical perspective

International Nuclear Information System (INIS)

Hunold, Peter; Schlosser, Thomas; Barkhausen, Joerg

2006-01-01

Coronary artery disease (CAD) with its clinical appearance of stable or unstable angina and acute myocardial infarction is the leading cause of death in developed countries. In view of increasing costs and the rising number of CAD patients, there has been a major interest in reliable non-invasive imaging techniques to identify CAD in an early (i.e. asymptomatic) stage. Since myocardial perfusion deficits appear very early in the ''ischemic cascade'', a major breakthrough would be the non-invasive quantification of myocardial perfusion before functional impairment might be detected. Therefore, there is growing interest in other, target-organ-specific parameters, such as relative and absolute myocardial perfusion imaging. Magnetic resonance (MR) imaging has been proven to offer attractive concepts in this respect. However, some important difficulties have not been resolved so far, which still causes uncertainty and prevents the broad application of MR perfusion imaging in a clinical setting. This review explores recent technical developments in MR hardware, software and contrast agents, as well as their impact on the current and future clinical status of MR imaging of first-pass myocardial perfusion imaging. (orig.)

Magnetic resonance cardiac perfusion imaging-a clinical perspective

Energy Technology Data Exchange (ETDEWEB)

Hunold, Peter; Schlosser, Thomas; Barkhausen, Joerg [University Hospital, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany)

2006-08-15

Coronary artery disease (CAD) with its clinical appearance of stable or unstable angina and acute myocardial infarction is the leading cause of death in developed countries. In view of increasing costs and the rising number of CAD patients, there has been a major interest in reliable non-invasive imaging techniques to identify CAD in an early (i.e. asymptomatic) stage. Since myocardial perfusion deficits appear very early in the ''ischemic cascade'', a major breakthrough would be the non-invasive quantification of myocardial perfusion before functional impairment might be detected. Therefore, there is growing interest in other, target-organ-specific parameters, such as relative and absolute myocardial perfusion imaging. Magnetic resonance (MR) imaging has been proven to offer attractive concepts in this respect. However, some important difficulties have not been resolved so far, which still causes uncertainty and prevents the broad application of MR perfusion imaging in a clinical setting. This review explores recent technical developments in MR hardware, software and contrast agents, as well as their impact on the current and future clinical status of MR imaging of first-pass myocardial perfusion imaging. (orig.)

Clinical feasibility of {sup 90}Y digital PET/CT for imaging microsphere biodistribution following radioembolization

Energy Technology Data Exchange (ETDEWEB)

Wright, Chadwick L.; Binzel, Katherine; Zhang, Jun; Knopp, Michael V. [The Ohio State University Wexner Medical Center, Wright Center of Innovation in Biomedical Imaging, Department of Radiology, Columbus, OH (United States); Wuthrick, Evan J. [The Ohio State University Wexner Medical Center, Department of Radiation Oncology, Columbus, OH (United States)

2017-07-15

The purpose of this study was to evaluate the clinical feasibility of next generation solid-state digital photon counting PET/CT (dPET/CT) technology and imaging findings in patients following {sup 90}Y microsphere radioembolization in comparison with standard of care (SOC) bremsstrahlung SPECT/CT (bSPECT/CT). Five patients underwent SOC {sup 90}Y bremsstrahlung imaging immediately following routine radioembolization with 3.5 ± 1.7 GBq of {sup 90}Y-labeled glass microspheres. All patients also underwent dPET/CT imaging at 29 ± 11 h following radioembolization. Matched pairs comparison was used to compare image quality, image contrast and {sup 90}Y biodistribution between dPET/CT and bSPECT/CT images. Volumetric assessments of {sup 90}Y activity using different isocontour thresholds on dPET/CT and bSPECT/CT images were also compared. Digital PET/CT consistently provided better visual image quality and {sup 90}Y-to-background image contrast while depicting {sup 90}Y biodistribution than bSPECT/CT. Isocontour volumetric assessment using a 1% threshold precisely outlined {sup 90}Y activity and the treatment volume on dPET/CT images, whereas a more restrictive 20% threshold on bSPECT/CT images was needed to obtain comparable treatment volumes. The use of a less restrictive 10% threshold isocontour on bSPECT/CT images grossly overestimated the treatment volume when compared with the 1% threshold on dPET/CT images. Digital PET/CT is clinically feasible for the assessment of {sup 90}Y microsphere biodistribution following radioembolization, and provides better visual image quality and image contrast than routine bSPECT/CT with comparable acquisition times. With further optimization and clinical validation, dPET technology may allow faster and more accurate imaging-based assessment of {sup 90}Y microsphere biodistribution. (orig.)

Incidental ferumoxytol artifacts in clinical brain MR imaging

Energy Technology Data Exchange (ETDEWEB)

Bowser, Bruce A.; Campeau, Norbert G.; Carr, Carrie M.; Diehn, Felix E.; McDonald, Jennifer S.; Miller, Gary M.; Kaufmann, Timothy J. [Mayo Clinic, Department of Radiology, Rochester, MN (United States)

2016-11-15

Ferumoxytol (Feraheme) is a parenteral therapy approved for treatment of iron deficiency anemia. The product insert for ferumoxytol states that it may affect the diagnostic ability of MRI for up to 3 months. However, the expected effects may not be commonly recognized among clinical neuroradiologists. Our purpose is to describe the artifacts we have seen at our institution during routine clinical practice. We reviewed the patients at our institution that had brain MRI performed within 90 days of receiving intravenous ferumoxytol. The imaging was reviewed for specific findings, including diffusion-weighted imaging vascular susceptibility artifact, gradient-echo echo-planar T2*-weighted vascular susceptibility artifact, SWI/SWAN vascular susceptibility artifact, hypointense vascular signal on T2-weighted images, pre-gadolinium contrast vascular enhancement on magnetization-prepared rapid acquisition gradient echo (MPRAGE) imaging, and effects on post-gadolinium contrast T1 imaging. Multiple artifacts were observed in patients having a brain MRI within 3 days of receiving intravenous ferumoxytol. These included susceptibility artifact on DWI, GRE, and SWAN/SWI imaging, pre-gadolinium contrast increased vascular signal on MPRAGE imaging, and decreased expected enhancement on post-gadolinium contrast T1-weighted imaging. Ferumoxytol can create imaging artifacts which complicate clinical interpretation when brain MRI is performed within 3 days of administration. Recognition of the constellation of artifacts produced by ferumoxytol is important in order to obviate additional unnecessary examinations and mitigate errors in interpretation. (orig.)

Clinical stage T1c prostate cancer: evaluation with endorectal MR imaging and MR spectroscopic imaging.

Science.gov (United States)

Zhang, Jingbo; Hricak, Hedvig; Shukla-Dave, Amita; Akin, Oguz; Ishill, Nicole M; Carlino, Lauren J; Reuter, Victor E; Eastham, James A

2009-11-01

To assess the diagnostic accuracy of endorectal magnetic resonance (MR) imaging and MR spectroscopic imaging for prediction of the pathologic stage of prostate cancer and the presence of clinically nonimportant disease in patients with clinical stage T1c prostate cancer. The institutional review board approved-and waived the informed patient consent requirement for-this HIPAA-compliant study involving 158 patients (median age, 58 years; age range, 40-76 years) who had clinical stage T1c prostate cancer, had not been treated preoperatively, and underwent combined 1.5-T endorectal MR imaging-MR spectroscopic imaging between January 2003 and March 2004 before undergoing radical prostatectomy. On the MR images and combined endorectal MR-MR spectroscopic images, two radiologists retrospectively and independently rated the likelihood of cancer in 12 prostate regions and the likelihoods of extracapsular extension (ECE), seminal vesicle invasion (SVI), and adjacent organ invasion by using a five-point scale, and they determined the probability of clinically nonimportant prostate cancer by using a four-point scale. Whole-mount step-section pathology maps were used for imaging-pathologic analysis correlation. Receiver operating characteristic curves were constructed and areas under the curves (AUCs) were estimated nonparametrically for assessment of reader accuracy. At surgical-pathologic analysis, one (0.6%) patient had no cancer; 124 (78%) patients, organ-confined (stage pT2) disease; 29 (18%) patients, ECE (stage pT3a); two (1%) patients, SVI (stage pT3b); and two (1%) patients, bladder neck invasion (stage pT4). Forty-six (29%) patients had a total tumor volume of less than 0.5 cm(3). With combined MR imaging-MR spectroscopic imaging, the two readers achieved 80% accuracy in disease staging and AUCs of 0.62 and 0.71 for the prediction of clinically nonimportant cancer. Clinical stage T1c prostate cancers are heterogeneous in pathologic stage and volume. MR imaging may

Parotid lymphomas - clinical and computed tomogrphic imaging ...

African Journals Online (AJOL)

Parotid lymphomas - clinical and computed tomogrphic imaging features. ... South African Journal of Surgery ... Lymphoma has a clinical presentation similar ... CT scanning is a useful adjunctive investigation to determine the site and extent of ...

SU-E-I-73: Clinical Evaluation of CT Image Reconstructed Using Interior Tomography

International Nuclear Information System (INIS)

Zhang, J; Ge, G; Winkler, M; Cong, W; Wang, G

2014-01-01

Purpose: Radiation dose reduction has been a long standing challenge in CT imaging of obese patients. Recent advances in interior tomography (reconstruction of an interior region of interest (ROI) from line integrals associated with only paths through the ROI) promise to achieve significant radiation dose reduction without compromising image quality. This study is to investigate the application of this technique in CT imaging through evaluating imaging quality reconstructed from patient data. Methods: Projection data were directly obtained from patients who had CT examinations in a Dual Source CT scanner (DSCT). Two detectors in a DSCT acquired projection data simultaneously. One detector provided projection data for full field of view (FOV, 50 cm) while another detectors provided truncated projection data for a FOV of 26 cm. Full FOV CT images were reconstructed using both filtered back projection and iterative algorithm; while interior tomography algorithm was implemented to reconstruct ROI images. For comparison reason, FBP was also used to reconstruct ROI images. Reconstructed CT images were evaluated by radiologists and compared with images from CT scanner. Results: The results show that the reconstructed ROI image was in excellent agreement with the truth inside the ROI, obtained from images from CT scanner, and the detailed features in the ROI were quantitatively accurate. Radiologists evaluation shows that CT images reconstructed with interior tomography met diagnosis requirements. Radiation dose may be reduced up to 50% using interior tomography, depending on patient size. Conclusion: This study shows that interior tomography can be readily employed in CT imaging for radiation dose reduction. It may be especially useful in imaging obese patients, whose subcutaneous tissue is less clinically relevant but may significantly increase radiation dose

Clinical application of subtraction CT imaging for evaluation of pulmonary vascular permeability

International Nuclear Information System (INIS)

Kato, Shiro; Asai, Toshihiko; Yatagai, Shigeo; Oonuma, Noboru; Ohno, Kunihiko; Nakamoto, Takaaki; Iizuka, Masahiko

1991-01-01

In this clinical study, one normal subject, one patient with primary interstitial pneumonia, one patient with segmental pneumonia due to Staphylococcus aureus, one patient with post-operative esophageal carcinoma, and two patients with mitral stenosis were studied. Dynamic CT scan images under continuous injection of low osmotic contrast medium were analyzed in series, in an attempt to evaluate vascular permeability quantitatively. The following results were obtained. Subtraction CT scan image 10 minutes after the start of contrast medium injection in two patients with pneumonia, showed a reduction of pulmonary vascular permeability following therapy. Subtraction CT scan image of the patient with post-operative esophageal carcinoma treated with 25 Gy radiation showed a discrepancy between pulmonary vascular permeability and other findings. In hemodynamically stable patients with mitral stenosis, subtraction CT images demonstrated that pulmonary vascular permeability was not affected by pulmonary congestion, irrespective of its severity. (author)

Joubert syndrome: Clinical manifestations and magnetic resonance imaging

International Nuclear Information System (INIS)

Kim, Seung Cheol; Kim, In One; Yoon, Yong Kyu; Yeon, Kyung Mo; Kim, Woo Sun; Song, Jong Gi; Hwang, Yong Seung

1994-01-01

Joubert syndrome presents neonatal respiratory abnormalities and other clinical manifestations. Pathologically the patients show hypoplasia or agenesis of cerebellar vermis and other intracranial anomalies. Our purpose is to evaluate the clinical manifestations and MR findings of Joubert syndrome. Among the patient presenting with clinical stigmata of Joubert syndrome and agenesis of vermis on MR imaging, eight patients who did not satisfied the criteria of Dandy-Walker malformation, tectocerebellar dysraphia and rhombencephalosynapsis were selected. MR findings and clinical manifestation were analyzed. On MR imaging, agenesis of the cerebellar vermis (all cases), hypoplasia of the cerebellar peduncle (6 cases), fourth ventricular contour deformity (6 cases), tentorial elevation (4 caes), deformity of the lateral ventricles (4 cases), dysgenesis of the straight sinus (3 cases) were demonstrated. Other findings were abnormalities of corpus callosum (3 cases), falx anomalies (3 case), occipital encephalomeningocele (2 cases) and fluid collection in posterior cranial fossa (2 cases). Clinical manifestations were developmental delay (5 cases), abnormal eyeball movement (3 cases), hypotonia (2 cases), neonatal respiratory abnormality (2 cases), etc. Joubert syndrome showed various clinical manifestations and intracranial anomalies. MR imaging is an useful modality in detection of the cerebellar vermian agenesis and other anomalies of the patients

Barrett's esophagus: clinical features, obesity, and imaging.

LENUS (Irish Health Repository)

Quigley, Eamonn M M

2011-09-01

The following includes commentaries on clinical features and imaging of Barrett\\'s esophagus (BE); the clinical factors that influence the development of BE; the influence of body fat distribution and central obesity; the role of adipocytokines and proinflammatory markers in carcinogenesis; the role of body mass index (BMI) in healing of Barrett\\'s epithelium; the role of surgery in prevention of carcinogenesis in BE; the importance of double-contrast esophagography and cross-sectional images of the esophagus; and the value of positron emission tomography\\/computed tomography.

Imaging photoplethysmography for clinical assessment of cutaneous microcirculation at two different depths

Science.gov (United States)

Marcinkevics, Zbignevs; Rubins, Uldis; Zaharans, Janis; Miscuks, Aleksejs; Urtane, Evelina; Ozolina-Moll, Liga

2016-03-01

The feasibility of bispectral imaging photoplethysmography (iPPG) system for clinical assessment of cutaneous microcirculation at two different depths is proposed. The iPPG system has been developed and evaluated for in vivo conditions during various tests: (1) topical application of vasodilatory liniment on the skin, (2) skin local heating, (3) arterial occlusion, and (4) regional anesthesia. The device has been validated by the measurements of a laser Doppler imager (LDI) as a reference. The hardware comprises four bispectral light sources (530 and 810 nm) for uniform illumination of skin, video camera, and the control unit for triggering of the system. The PPG signals were calculated and the changes of perfusion index (PI) were obtained during the tests. The results showed convincing correlations for PI obtained by iPPG and LDI at (1) topical liniment (r=0.98) and (2) heating (r=0.98) tests. The topical liniment and local heating tests revealed good selectivity of the system for superficial microcirculation monitoring. It is confirmed that the iPPG system could be used for assessment of cutaneous perfusion at two different depths, morphologically and functionally different vascular networks, and thus utilized in clinics as a cost-effective alternative to the LDI.

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.

Functional brain imaging - baric and clinical questions

International Nuclear Information System (INIS)

Mager, T.; Moeller, H.J.

1997-01-01

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

Microvascular imaging: techniques and opportunities for clinical physiological measurements

International Nuclear Information System (INIS)

Allen, John; Howell, Kevin

2014-01-01

The microvasculature presents a particular challenge in physiological measurement because the vessel structure is spatially inhomogeneous and perfusion can exhibit high variability over time. This review describes, with a clinical focus, the wide variety of methods now available for imaging of the microvasculature and their key applications. Laser Doppler perfusion imaging and laser speckle contrast imaging are established, commercially-available techniques for determining microvascular perfusion, with proven clinical utility for applications such as burn-depth assessment. Nailfold capillaroscopy is also commercially available, with significant published literature that supports its use for detecting microangiopathy secondary to specific connective tissue diseases in patients with Raynaud's phenomenon. Infrared thermography measures skin temperature and not perfusion directly, and it has only gained acceptance for some surgical and peripheral microvascular applications. Other emerging technologies including imaging photoplethysmography, optical coherence tomography, photoacoustic tomography, hyperspectral imaging, and tissue viability imaging are also described to show their potential as techniques that could become established tools for clinical microvascular assessment. Growing interest in the microcirculation has helped drive the rapid development in perfusion imaging of the microvessels, bringing exciting opportunities in microvascular research. (topical review)

Magnetic resonance imaging in perinatal brain injury: clinical presentation, lesions and outcome

Energy Technology Data Exchange (ETDEWEB)

Rutherford, Mary; Ward, Phil; Allsop, Joanna; Counsell, Serena [Imperial College London, Hammersmith Hospital, Robert Steiner MR Unit, Imaging Sciences Department, Clinical Sciences Centre, London (United Kingdom); Srinivasan, Latha; Dyet, Leigh; Cowan, Frances [Imperial College, Hammersmith Hospital, Department of Paediatrics, Imaging Sciences Department, Clinical Sciences Centre, London (United Kingdom)

2006-07-15

Neonatal MR imaging is invaluable in assessing the term born neonate who presents with an encephalopathy. Successful imaging requires adaptations to both the hardware and the sequences used for adults. The perinatal and postnatal details often predict the pattern of lesions sustained and are essential for correct interpretation of the imaging findings, but additional or alternative diagnoses in infants with apparent hypoxic ischaemic encephalopathy should always be considered. Perinatally acquired lesions are usually at their most obvious between 1 and 2 weeks of age. Very early imaging (<3 days) may be useful to make management decisions in ventilated neonates, but abnormalities may be subtle at that stage. Diffusion-weighted imaging is clinically useful for the early identification of ischaemic white matter in the neonatal brain but is less reliable in detecting lesions within the basal ganglia and thalami. The pattern of lesions seen on MRI can predict neurodevelopmental outcome. Additional useful information may be obtained by advanced techniques such as MR angiography, venography and perfusion-weighted imaging. Serial imaging with quantification of both structure size and tissue damage provides invaluable insights into perinatal brain injury. (orig.)

Basics concepts and clinical applications of oxygen-enhanced MR imaging

International Nuclear Information System (INIS)

Ohno, Yoshiharu; Hatabu, Hiroto

2007-01-01

Oxygen-enhanced MR imaging is a new technique, and its physiological significance has not yet been fully elucidated. This review article covers (1) the theory of oxygen enhancement and its relationship with respiratory physiology; (2) design for oxygen-enhanced MR imaging sequencing; (3) a basic study of oxygen-enhanced MR imaging in animal models and humans; (4) a clinical study of oxygen-enhanced MR imaging; and (5) a comparison of advantages and disadvantages of this technique with those of hyperpolarized noble gas MR ventilation imaging. Oxygen-enhanced MR imaging provides not only the ventilation-related, but also respiration-related information. Oxygen-enhanced MR imaging has the potential to replace nuclear medicine studies for the identification of regional pulmonary function, and many investigators are now attempting to adapt this technique for routine clinical studies. We believe that further basic studies as well as clinical applications of this new technique will define the real significance of oxygen-enhanced MR imaging for the future of pulmonary functional imaging and its usefulness for diagnostic radiology and pulmonary medicine

Clinical software for MR imaging system, 4

International Nuclear Information System (INIS)

Shimizu, Koji; Kasai, Akira; Okamura, Shoichi

1992-01-01

Magnetic resonance imaging continues to elicit new application software through the recent technological advances of MR equipment. This paper describes several applications of our newly developed clinical software. The fast SE sequence (RISE) has proved to reduce routine examination time and to improve image quality, and ultra-fast FE sequence (SMASH) was found to extend the diagnostic capabilities in the field of cardiac study. Diffusion/perfusion imaging achieved in our MR system showed significant promise for providing novel information regarding tissue characterization. Furthermore, Image quality and practicalities of MR angiography have been improved by advanced imaging sequences and sophisticated post-processing software. (author)

Technical and clinical evaluation of an improved-contrast screen-film combination for radiation therapy portal localization imaging

International Nuclear Information System (INIS)

Haus, Arthur G.; Dickerson, Robert E.; Huff, Kenneth E.; Monte, Suzanne; Schlager, Barbara A.; Atanas, Meri; Matloubieh, Ahmad

1996-01-01

Purpose/Objective: A problem with conventional radiation therapy portal images is low image contrast, due in part to the low attenuation of the exposing radiation by the anatomical parts being imaged and the contrast capabilities of the film or screen-film combination. The purpose of this study was to design, develop and clinically evaluate a new screen-film combination for portal localization imaging which provides significantly higher contrast and therefore improved image quality. Materials and Methods: Comparison phantom and clinical images were made at two radiation oncology facilities with the new prototype screen-film combination and a commercial screen-film combination currently used for portal localization imaging. All images were made with linear accelerators at 6MV. Sensitometric data was also obtained. The prototype combination features a 1.0mm copper front screen plus front and back gadolinium oxysulfide fluorescent intensifying screens and a very-slow-speed film having inherently high contrast. The film emulsion layers are coated on a 7 mil Estar base which allows processing in a conventional rapid process film processor. For this combination, the film is exposed primarily by light from the intensifying screens. The current, commercially available screen-film combination was a Kodak X-Omatic L Radiation Therapy Cassette with a 1.0mm copper front screen and a 0.25mm lead back screen and Kodak X-Omat RP film in ready pack envelope. With this combination, the film emulsion is exposed by electrons generated in the metal screens. All films were processed in a Kodak M35A X-Omat processor. Radiation oncologists reviewed the phantom and clinical images. Results: Sensitometric data indicate that the film contrast (average gradient) of the new prototype combination is approximately 4 times higher than the conventional commercially available combination. Phantom and clinical comparisons at St. Mary Cancer Center, Langhorne PA. and the Daisy Marquis Jones

Molecular imaging in nanomedicine - A developmental tool and a clinical necessity.

Science.gov (United States)

Dearling, Jason L J; Packard, Alan B

2017-09-10

The development of nanomedicines presents the potential to deliver more potent drugs targeted more specifically to the site(s) of disease than is currently achievable. While encouraging results have been achieved, including at the clinical level, significant challenges and opportunities for development remain, both in terms of further developing the technology and in understanding the underlying biology. Given the lessons learned regarding variations in nanomedicine delivery to different tumor types and between different patients with the same tumor type, this is an area of drug development that, rather than simply benefiting from a patient-specific approach, actually demands it. The only way that this distribution information can be obtained is through imaging, and this requires labeling of the nanomedicine to enable detection outside the body. In this review, we describe recent advances in the labeling of nanomedicines, how imaging studies are guiding nanomedicine development, and the role of imaging in the future development of nanomedicines. Copyright © 2017 Elsevier B.V. All rights reserved.

A hand-held imaging probe for radio-guided surgery: physical performance and preliminary clinical experience

International Nuclear Information System (INIS)

Pitre, S.; Menard, L.; Charon, Y.; Solal, M.; Garbay, J.R.

2003-01-01

Improvements in the specificity of radiopharmaceutical compounds have been paralleled by an upsurge of interest in developing small detectors to assist surgeons in localizing tumour tissue during surgery. This study reports the main technical features and physical characteristics of a new hand-held gamma camera dedicated to accurate and real-time intra-operative imaging. First clinical experience is also reported. The POCI (Per-operative Compact Imager) camera consists of a head module composed of a high-resolution interchangeable lead collimator and a CsI(Na) crystal plate optically coupled to an intensified position-sensitive diode. The current prototype has a 40-mm diameter field of view, an outer diameter of 9.5 cm, a length of 9 cm and a weight of 1.2 kg. Overall detector imaging characteristics were evaluated by technetium-99m phantom measurements. Three patients with breast cancer previously scheduled to undergo sentinel lymph node detection were selected for the preliminary clinical experience. Preoperative images of the lymphatic basin obtained using the POCI camera were compared with conventional transcutaneous explorations using a non-imaging gamma probe. The full-width at half-maximum (FWHM) spatial resolution was investigated in both air and scattering medium; when the phantom was placed in contact with the collimator, the POCI camera exhibited a 3.2 mm FWHM. The corresponding sensitivity was 290 cps/MBq. The preliminary clinical results showed that POCI was able to predict the number and location of all SLNs. In one case, two deep radioactive nodes missed by the gamma probe were detected on the intra-operative images. This very initial experience demonstrates that the physical performance of the POCI camera is adequate for radio-guided surgery. These results are sufficiently encouraging to prompt further evaluation studies designed to determine the specific and optimal clinical role of intra-operative imaging devices

Clinical usefulness of physiological components obtained by factor analysis. Application to /sup 99m/Tc-DTPA renography

Energy Technology Data Exchange (ETDEWEB)

Ohtake, Eiji; Murata, Hajime; Matsuda, Hirofumi; Yokoyama, Masao; Toyama, Hinako; Satoh, Tomohiko.

1989-01-01

The clinical usefulness of physiological components obtained by factor analysis was assessed in /sup 99m/Tc-DTPA renography. Using definite physiological components, another dynamic data could be analyzed. In this paper, the dynamic renal function after ESWL (Extracorporeal Shock Wave Lithotripsy) treatment was examined using physiological components in the kidney before ESWL and/or a normal kidney. We could easily evaluate the change of renal functions by this method. The usefulness of a new analysis using physiological components was summarized as follows: (1) The change of a dynamic function could be assessed in quantity as that of the contribution ratio. (2) The change of a sick condition could be morphologically evaluated as that of the functional image.

Imaging and Data Acquisition in Clinical Trials for Radiation Therapy

Energy Technology Data Exchange (ETDEWEB)

FitzGerald, Thomas J., E-mail: Thomas.Fitzgerald@umassmed.edu [Imaging and Radiation Oncology Core Rhode Island, University of Massachusetts Memorial Medical Center, University of Massachusetts Medical School, Worcester, Massachusetts (United States); Bishop-Jodoin, Maryann [Imaging and Radiation Oncology Core Rhode Island, University of Massachusetts Medical School, Worcester, Massachusetts (United States); Followill, David S. [Imaging and Radiation Oncology Core Houston, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Galvin, James [Imaging and Radiation Oncology Core Philadelphia, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Knopp, Michael V. [Imaging and Radiation Oncology Core Ohio, Wexner Medical Center, Ohio State University, Columbus, Ohio (United States); Michalski, Jeff M. [Imaging and Radiation Oncology Core St. Louis, Washington University School of Medicine, St. Louis, Missouri (United States); Rosen, Mark A. [Imaging and Radiation Oncology Core Philadelphia, University of Pennsylvania Health System, Philadelphia, Pennsylvania (United States); Bradley, Jeffrey D. [Washington University School of Medicine–Radiation Oncology, St. Louis, Missouri (United States); Shankar, Lalitha K. [National Cancer Institute, Clinical Radiation Oncology Branch, Rockville, Maryland (United States); Laurie, Fran [Imaging and Radiation Oncology Core Rhode Island, University of Massachusetts Medical School, Worcester, Massachusetts (United States); Cicchetti, M. Giulia; Moni, Janaki [Imaging and Radiation Oncology Core Rhode Island, University of Massachusetts Memorial Medical Center, University of Massachusetts Medical School, Worcester, Massachusetts (United States); Coleman, C. Norman; Deye, James A.; Capala, Jacek; Vikram, Bhadrasain [National Cancer Institute, Clinical Radiation Oncology Branch, Rockville, Maryland (United States)

2016-02-01

Cancer treatment evolves through oncology clinical trials. Cancer trials are multimodal and complex. Assuring high-quality data are available to answer not only study objectives but also questions not anticipated at study initiation is the role of quality assurance. The National Cancer Institute reorganized its cancer clinical trials program in 2014. The National Clinical Trials Network (NCTN) was formed and within it was established a Diagnostic Imaging and Radiation Therapy Quality Assurance Organization. This organization is Imaging and Radiation Oncology Core, the Imaging and Radiation Oncology Core Group, consisting of 6 quality assurance centers that provide imaging and radiation therapy quality assurance for the NCTN. Sophisticated imaging is used for cancer diagnosis, treatment, and management as well as for image-driven technologies to plan and execute radiation treatment. Integration of imaging and radiation oncology data acquisition, review, management, and archive strategies are essential for trial compliance and future research. Lessons learned from previous trials are and provide evidence to support diagnostic imaging and radiation therapy data acquisition in NCTN trials.

Imaging and Data Acquisition in Clinical Trials for Radiation Therapy

International Nuclear Information System (INIS)

FitzGerald, Thomas J.; Bishop-Jodoin, Maryann; Followill, David S.; Galvin, James; Knopp, Michael V.; Michalski, Jeff M.; Rosen, Mark A.; Bradley, Jeffrey D.; Shankar, Lalitha K.; Laurie, Fran; Cicchetti, M. Giulia; Moni, Janaki; Coleman, C. Norman; Deye, James A.; Capala, Jacek; Vikram, Bhadrasain

2016-01-01

Cancer treatment evolves through oncology clinical trials. Cancer trials are multimodal and complex. Assuring high-quality data are available to answer not only study objectives but also questions not anticipated at study initiation is the role of quality assurance. The National Cancer Institute reorganized its cancer clinical trials program in 2014. The National Clinical Trials Network (NCTN) was formed and within it was established a Diagnostic Imaging and Radiation Therapy Quality Assurance Organization. This organization is Imaging and Radiation Oncology Core, the Imaging and Radiation Oncology Core Group, consisting of 6 quality assurance centers that provide imaging and radiation therapy quality assurance for the NCTN. Sophisticated imaging is used for cancer diagnosis, treatment, and management as well as for image-driven technologies to plan and execute radiation treatment. Integration of imaging and radiation oncology data acquisition, review, management, and archive strategies are essential for trial compliance and future research. Lessons learned from previous trials are and provide evidence to support diagnostic imaging and radiation therapy data acquisition in NCTN trials.

CT Image Contrast of High-Z Elements: Phantom Imaging Studies and Clinical Implications.

Science.gov (United States)

FitzGerald, Paul F; Colborn, Robert E; Edic, Peter M; Lambert, Jack W; Torres, Andrew S; Bonitatibus, Peter J; Yeh, Benjamin M

2016-03-01

To quantify the computed tomographic (CT) image contrast produced by potentially useful contrast material elements in clinically relevant imaging conditions. Equal mass concentrations (grams of active element per milliliter of solution) of seven radiodense elements, including iodine, barium, gadolinium, tantalum, ytterbium, gold, and bismuth, were formulated as compounds in aqueous solutions. The compounds were chosen such that the active element dominated the x-ray attenuation of the solution. The solutions were imaged within a modified 32-cm CT dose index phantom at 80, 100, 120, and 140 kVp at CT. To simulate larger body sizes, 0.2-, 0.5-, and 1.0-mm-thick copper filters were applied. CT image contrast was measured and corrected for measured concentrations and presence of chlorine in some compounds. Each element tested provided higher image contrast than iodine at some tube potential levels. Over the range of tube potentials that are clinically practical for average-sized and larger adults-that is, 100 kVp and higher-barium, gadolinium, ytterbium, and tantalum provided consistently increased image contrast compared with iodine, respectively demonstrating 39%, 56%, 34%, and 24% increases at 100 kVp; 39%, 66%, 53%, and 46% increases at 120 kVp; and 40%, 72%, 65%, and 60% increases at 140 kVp, with no added x-ray filter. The consistently high image contrast produced with 100-140 kVp by tantalum compared with bismuth and iodine at equal mass concentration suggests that tantalum could potentially be favorable for use as a clinical CT contrast agent.

Markerless motion estimation for motion-compensated clinical brain imaging

Science.gov (United States)

Kyme, Andre Z.; Se, Stephen; Meikle, Steven R.; Fulton, Roger R.

2018-05-01

Motion-compensated brain imaging can dramatically reduce the artifacts and quantitative degradation associated with voluntary and involuntary subject head motion during positron emission tomography (PET), single photon emission computed tomography (SPECT) and computed tomography (CT). However, motion-compensated imaging protocols are not in widespread clinical use for these modalities. A key reason for this seems to be the lack of a practical motion tracking technology that allows for smooth and reliable integration of motion-compensated imaging protocols in the clinical setting. We seek to address this problem by investigating the feasibility of a highly versatile optical motion tracking method for PET, SPECT and CT geometries. The method requires no attached markers, relying exclusively on the detection and matching of distinctive facial features. We studied the accuracy of this method in 16 volunteers in a mock imaging scenario by comparing the estimated motion with an accurate marker-based method used in applications such as image guided surgery. A range of techniques to optimize performance of the method were also studied. Our results show that the markerless motion tracking method is highly accurate (brain imaging and holds good promise for a practical implementation in clinical PET, SPECT and CT systems.

Fat suppression techniques for obtaining high resolution dynamic contrast enhanced bilateral breast MR images at 7 tesla

DEFF Research Database (Denmark)

van der Velden, Tijl A; Schmitz, Alexander M Th; Gilhuijs, Kenneth G A

2016-01-01

contained 3D T1-weighted gradient echo images obtained with both WSE fat suppression, multi echo Dixon fat suppression, and without fat suppression. Images were acquired at a (0.8mm)(3) or (0.7mm)(3) isotropic resolution with equal field of view and optimized such to obtain a maximal SNR. Image quality...... was scored qualitatively on overall image quality, sharpness of anatomical details, presence of artefacts, inhomogeneous fat suppression and the presence of water-fat shift. A quantitative scoring was obtained from the signal to noise ratio and contrast to noise ratio. RESULTS: WSE scored significantly...... better in terms of overall image quality and the absence of artefacts. No significant difference in contrast to noise ratio was found between the two fat suppression methods. CONCLUSION: When maximizing temporal and spatial resolution of high resolution DCE MRI of the breast, water selective excitation...

Super-resolution for everybody: An image processing workflow to obtain high-resolution images with a standard confocal microscope.

Science.gov (United States)

Lam, France; Cladière, Damien; Guillaume, Cyndélia; Wassmann, Katja; Bolte, Susanne

2017-02-15

In the presented work we aimed at improving confocal imaging to obtain highest possible resolution in thick biological samples, such as the mouse oocyte. We therefore developed an image processing workflow that allows improving the lateral and axial resolution of a standard confocal microscope. Our workflow comprises refractive index matching, the optimization of microscope hardware parameters and image restoration by deconvolution. We compare two different deconvolution algorithms, evaluate the necessity of denoising and establish the optimal image restoration procedure. We validate our workflow by imaging sub resolution fluorescent beads and measuring the maximum lateral and axial resolution of the confocal system. Subsequently, we apply the parameters to the imaging and data restoration of fluorescently labelled meiotic spindles of mouse oocytes. We measure a resolution increase of approximately 2-fold in the lateral and 3-fold in the axial direction throughout a depth of 60μm. This demonstrates that with our optimized workflow we reach a resolution that is comparable to 3D-SIM-imaging, but with better depth penetration for confocal images of beads and the biological sample. Copyright © 2016 Elsevier Inc. All rights reserved.

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.

Exploring the feasibility of iris recognition for visible spectrum iris images obtained using smartphone camera

Science.gov (United States)

Trokielewicz, Mateusz; Bartuzi, Ewelina; Michowska, Katarzyna; Andrzejewska, Antonina; Selegrat, Monika

2015-09-01

In the age of modern, hyperconnected society that increasingly relies on mobile devices and solutions, implementing a reliable and accurate biometric system employing iris recognition presents new challenges. Typical biometric systems employing iris analysis require expensive and complicated hardware. We therefore explore an alternative way using visible spectrum iris imaging. This paper aims at answering several questions related to applying iris biometrics for images obtained in the visible spectrum using smartphone camera. Can irides be successfully and effortlessly imaged using a smartphone's built-in camera? Can existing iris recognition methods perform well when presented with such images? The main advantage of using near-infrared (NIR) illumination in dedicated iris recognition cameras is good performance almost independent of the iris color and pigmentation. Are the images obtained from smartphone's camera of sufficient quality even for the dark irides? We present experiments incorporating simple image preprocessing to find the best visibility of iris texture, followed by a performance study to assess whether iris recognition methods originally aimed at NIR iris images perform well with visible light images. To our best knowledge this is the first comprehensive analysis of iris recognition performance using a database of high-quality images collected in visible light using the smartphones flashlight together with the application of commercial off-the-shelf (COTS) iris recognition methods.

Unique roles of SPET brain imaging in clinical and research studies

International Nuclear Information System (INIS)

Seibyl, J.; Jennings, D.; Tabamo, R.; Marek, K.

2005-01-01

The increasing availability of PET imaging in Nuclear medicine expands the armamentarium of clinical and research tools for improving diagnosis and treatment of neuropsychiatric disorders. Nonetheless, the role of SPEC imaging remains critical to both research and clinical practice. The development of rational strategies for guiding the selection of imaging modalities flows from primarily the nature of the clinical or research question and the availability of appropriate radiopharmaceuticals. There has been extensive SPECT and PET work in Parkinson's disease (PD) which highlights the value of both these scintigraphic modalities. Three main areas of interest in PD include imaging for improving diagnostic accuracy, for monitoring the progression of disease, and for assessing the therapeutic efficacy of drugs with neoroprotective potential. The demands of the clinical or research question posed to imaging dictates the selection of radiotracer and imaging modality. Diagnosis of PD represents the easiest challenge with many imaging bio markers showing high sensitivity for detecting abnormal reduction of dopaminergic function based on qualitative review of images. On the other hand, using imaging to evaluate treatments which purportedly slow the rate of disease progression, indicated by the reduction of the rate of loss in a quantitative imaging signal in patients studied over time, represents the most rigorous requirement of the imaging measure. In each of these applications presynaptic markers of dopaminergic function using SPECT and PET have been extremely valuable. Review of neuroimaging studies of PD provides a useful example of optimized approaches to clinical and research studies in neuropsychiatric disorders

Fuzzy Logic Based Edge Detection in Smooth and Noisy Clinical Images.

Directory of Open Access Journals (Sweden)

Izhar Haq

Full Text Available Edge detection has beneficial applications in the fields such as machine vision, pattern recognition and biomedical imaging etc. Edge detection highlights high frequency components in the image. Edge detection is a challenging task. It becomes more arduous when it comes to noisy images. This study focuses on fuzzy logic based edge detection in smooth and noisy clinical images. The proposed method (in noisy images employs a 3 × 3 mask guided by fuzzy rule set. Moreover, in case of smooth clinical images, an extra mask of contrast adjustment is integrated with edge detection mask to intensify the smooth images. The developed method was tested on noise-free, smooth and noisy images. The results were compared with other established edge detection techniques like Sobel, Prewitt, Laplacian of Gaussian (LOG, Roberts and Canny. When the developed edge detection technique was applied to a smooth clinical image of size 270 × 290 pixels having 24 dB 'salt and pepper' noise, it detected very few (22 false edge pixels, compared to Sobel (1931, Prewitt (2741, LOG (3102, Roberts (1451 and Canny (1045 false edge pixels. Therefore it is evident that the developed method offers improved solution to the edge detection problem in smooth and noisy clinical images.

Growth hormone-secreting pituitary adenoma:clinical and MR imaging findings

International Nuclear Information System (INIS)

Park, Hong Suk; Chang, Kee Hyun; Han, Moon Hee; Sim, Jung Suk; Lee, Sang Hyun; Song, Jae Uoo; Yoo, In Kyu; Jung, Hee Won; Yeon, Kyung Mo

1996-01-01

To describe clinical and MRI findings of growth hormone-secreting pituitary adenoma, to determine if there are any characteristic MRI findings different from those of other pituitary adenomas, to evaluate the relationship between tumor size and serum growth hormone level, and to assess the results of immunohi-stochemical study. We retrospectively analysed clinical and MRI findings of 29 patients with growth hormone-secreting pituitary adenoma confirmed by serum growth hormone level and surgery. We also evaluated the relationship between the tumor volume and serum growth hormone level, and the results of immunohistochemical study. Coronal and sagittal T1-weighted MR images in all patients and gadolinium-enhanced T1-weighted MR images in 28 patients were obtained with 2.0 T(24 cases) and 0.5 T(5 cases) MR imagers. The images were analyzed in terms of tumor size, signal intensity, degree of contrast enhancement, extent of tumor growth and the presence or absence of cystic change, hemorrhage and calcification. Clinical manifestations included facial feature change and soft tissue swelling of hands and feet(n=29), headache(n=12), impaired visual acuity(n=9), symptoms of hyperprolactinemia(n=8), visual field defect(n=5), and others(n=6). On MR images, all of the 29 cases were seen to be macroadenomas and the size of the tumors averaged 2.2cm(1-5.2cm). Supra- and infrasellar extensions were seen in 21 and 22 patients, respectively. Cavernous sinus invasion was noted in seven, and in one this was bilateral. Signal intensity was isointense with cortical grey matter in 26 cases(90%). Cystic change or necrosis was seen in eight cases(28%), hemorrhage in four(14%), and calcification in two(7%). After enhancement, most(25/28) of the tumors enhanced less than normal pituitary in degree. There was no correlation between serum growth hormone level and tumor size. Immunohistochemical study showed positive growth hormone-secreting pituitary adenomas were various and included

Growth hormone-secreting pituitary adenoma:clinical and MR imaging findings

Energy Technology Data Exchange (ETDEWEB)

Park, Hong Suk; Chang, Kee Hyun; Han, Moon Hee; Sim, Jung Suk; Lee, Sang Hyun; Song, Jae Uoo; Yoo, In Kyu; Jung, Hee Won; Yeon, Kyung Mo [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

1996-10-01

To describe clinical and MRI findings of growth hormone-secreting pituitary adenoma, to determine if there are any characteristic MRI findings different from those of other pituitary adenomas, to evaluate the relationship between tumor size and serum growth hormone level, and to assess the results of immunohi-stochemical study. We retrospectively analysed clinical and MRI findings of 29 patients with growth hormone-secreting pituitary adenoma confirmed by serum growth hormone level and surgery. We also evaluated the relationship between the tumor volume and serum growth hormone level, and the results of immunohistochemical study. Coronal and sagittal T1-weighted MR images in all patients and gadolinium-enhanced T1-weighted MR images in 28 patients were obtained with 2.0 T(24 cases) and 0.5 T(5 cases) MR imagers. The images were analyzed in terms of tumor size, signal intensity, degree of contrast enhancement, extent of tumor growth and the presence or absence of cystic change, hemorrhage and calcification. Clinical manifestations included facial feature change and soft tissue swelling of hands and feet(n=29), headache(n=12), impaired visual acuity(n=9), symptoms of hyperprolactinemia(n=8), visual field defect(n=5), and others(n=6). On MR images, all of the 29 cases were seen to be macroadenomas and the size of the tumors averaged 2.2cm(1-5.2cm). Supra- and infrasellar extensions were seen in 21 and 22 patients, respectively. Cavernous sinus invasion was noted in seven, and in one this was bilateral. Signal intensity was isointense with cortical grey matter in 26 cases(90%). Cystic change or necrosis was seen in eight cases(28%), hemorrhage in four(14%), and calcification in two(7%). After enhancement, most(25/28) of the tumors enhanced less than normal pituitary in degree. There was no correlation between serum growth hormone level and tumor size. Immunohistochemical study showed positive growth hormone-secreting pituitary adenomas were various and included

Clinical PET/CT imaging. Promises and misconceptions

International Nuclear Information System (INIS)

Czernin, J.; Auerbach, M.A.

2005-01-01

PET/CT is now established as the most important imaging tool in oncology. PET/CT stages and restages cancer with a higher accuracy than PET or CT alone. The sometimes irrational approach to combine state of the art PET with the highest end CT devices should give way to a more reasonable equipment design tailored towards the specific clinical indications in well-defined patient populations. The continuing success of molecular PET/CT now depends more upon advances in molecular imaging with the introduction of targeted imaging probes for individualized therapy approaches in cancer patients and less upon technological advances of imaging equipment. (orig.)

METHOD FOR CREATION OF SPHERICAL PANORAMAS FROM IMAGES OBTAINED BY OMNIDIRECTIONAL OPTOELECTRONIC SYSTEMS

Directory of Open Access Journals (Sweden)

V. P. Lazarenko

2016-01-01

Full Text Available Subject of Study. The key feature of spherical panoramas is the maximum possible angle of view (360 × 180 degrees. Omnidirectional optical-electronic systems are able to produce images that show most of this space, but these images are different from the canonical spherical panoramas. This paper proposes a method of converting the circular images obtained by omnidirectional optical systems, to canonical spherical panoramic images with the use ofcalibration procedure of omnidirectional optical-electronic system. Method. The process of spherical panoramas creation consists of three steps.The first step includesthe forming of virtual surface in the object space corresponding to a field of view of the spherical panorama. The surface is defined by the three-dimensional array of pixels.At the second step the coordinates of images of these points in the plane of the detectorare specified. At the third step pixel-by-pixel forming of the output imageisperformed from the original omnidirectional image with the use of coordinates obtained at the second step. Main Results. We have considered the geometric projectionmodel of spherical panoramas. The algorithm has been proposed calculating the three-dimensional array of pixels, characterizing the field of view of a spherical panorama and convenient for practical usage. The developed method is designed to work with omnidirectional optical-electronic systems both with catadioptric optical systems and with fisheye lens. Experimental results confirming the validity of this method are presented. The reprojection mean-square error was equal to 0.794 px. Practical Relevance. The proposed method can be applied in technologies of creating of virtual tours or panoramas of streets where spherical panoramic images are the standard for storing visual information. The method may also find its application in various fields of robotics, orientation and navigation of space vehicles and UAVs.

Progress toward clinical implementation of the first flat-panel amorphous silicon imager

International Nuclear Information System (INIS)

Antonuk, Larry E.; El-Mohri, Youcef; Weidong, Huang; Sandler, Howard; Siewerdsen, Jeffrey H.; Yorkston, John

1995-01-01

Purpose: Approximately 7 years after the development of the general concept, megavoltage imagers based on thin-film, flat-panel electronics will likely enter routine clinical use within the next few years. In this paper, current capabilities and anticipated development of this imaging technology as pertains to clinical use will be presented. The results of the first use of this technology with an early prototype imager in a clinical setting are reported. The development of a more advanced clinical prototype imager designed for routine clinical use is described and the clinically-relevant capabilities, advantages, and limitations of this device are described. Materials and Methods: Flat-panel amorphous silicon imagers consist of an imaging array, an x-ray converter, external data acquisition electronics, along with appropriate software and a host workstation. The array consists of a two-dimensional grid of imaging pixels with each pixel consisting of a transistor coupled to a photodiode. An initial study of patient imaging has been performed with an early prototype imager which incorporates a 512x560 array with 450 μm pixels giving an imaging surface of 23x25 cm 2 . Portal images acquired with this prototype imager and with film under similar geometric and irradiation conditions were acquired and compared. In addition, a clinical prototype imager based upon a 26x26 cm 2 array with 508 μm pixels (512x512 pixels) is under development. This prototype incorporates advanced analog and digital external electronics which will improve imaging performance thereby increasing clinical utility of the device. The imagers are interfaced to the operation of a treatment machine so as to allow both radiographic and fluoroscopic operation. Results: The image quality is limited by the presence of pixel and line defects in the array and by the presence of correlated and uncorrelated noise sources in the acquisition system. Nevertheless, the contrast and spatial resolution offered by

Clinical images evaluation of mammograms: a national survey

International Nuclear Information System (INIS)

Moon, Woo Kyung; Kim, Tae Jung; Cha, Joo Hee

2003-01-01

The goal of this study was to survey the overall quality of mammographic images in Korea. A total of 598 mammographic images collected from 257 hospitals nationwide were reviewed in terms of eight images quality categories, namely positioning, compression, contrast, exposure, sharpness, noise, artifacts, and examination identification, and rated on a five-point scale: (1=severe deficiency, 2=major deficiency, 3=minor deficiency, 4=good, 5=best). Failure was defined as the occurrence of more than four major deficiencies or one severe deficiency (score of 1 or 2). The results were compared among hospitals of varying kinds, and common problems in clinical images quality were identified. Two hundred and seventeen mammographic images (36.3%) failed the evaluation. Poor images were found in descending order of frequency, at The Society for Medical Examination (33/69, 47.8%), non-radiologyclinics (42/88, 47.7%), general hospitals (92/216, 42.6%), radiology clinics (39/102, 38.2%), and university hospitals (11/123, 8.9%) (p<0.01, Chi-square test). Among the 598 images, serious problems which occurred were related to positioning in 23.7% of instances (n=142) (p<0.01, Chi-square test), examination identification in 5.7% (n=34), exposure in 5.4% (n=32), contrast in 4.2% (n=25), sharpness in 2.7% (n=16), compression in 2.5% (n=15), artifacts in 2.5% (n=15), and noise in 0.3% (n=2). This study showed that in Korea, 36.3% of the mammograms examined in this sampling had important image-related defects that might have led to serious errors in patient management. The failure rate was significantly higher in non-radiology clinics and at The Society for Medical Examination than at university hospitals

TH-A-18A-01: Innovation in Clinical Breast Imaging

International Nuclear Information System (INIS)

Liu, B; Yang, K; Yaffe, M; Chen, J

2014-01-01

Several novel modalities have been or are on the verge of being introduced into the breast imaging clinic. These include tomosynthesis imaging, dedicated breast CT, contrast-enhanced digital mammography, and automated breast ultrasound, all of which are covered in this course. Tomosynthesis and dedicated breast CT address the problem of tissue superimposition that limits mammography screening performance, by improved or full resolution of the 3D breast morphology. Contrast-enhanced digital mammography provides functional information that allows for visualization of tumor angiogenesis. 3D breast ultrasound has high sensitivity for tumor detection in dense breasts, but the imaging exam was traditionally performed by radiologists. In automated breast ultrasound, the scan is performed in an automated fashion, making for a more practical imaging tool, that is now used as an adjunct to digital mammography in breast cancer screening. This course will provide medical physicists with an in-depth understanding of the imaging physics of each of these four novel imaging techniques, as well as the rationale and implementation of QC procedures. Further, basic clinical applications and work flow issues will be discussed. Learning Objectives: To be able to describe the underlying physical and physiological principles of each imaging technique, and to understand the corresponding imaging acquisition process. To be able to describe the critical system components and their performance requirements. To understand the rationale and implementation of quality control procedures, as well as regulatory requirements for systems with FDA approval. To learn about clinical applications and understand risks and benefits/strength and weakness of each modality in terms of clinical breast imaging

The Usefulness of Readout-Segmented Echo-Planar Imaging (RESOLVE) for Bio-phantom Imaging Using 3-Tesla Clinical MRI.

Science.gov (United States)

Yoshimura, Yuuki; Kuroda, Masahiro; Sugiantoc, Irfan; Bamgbosec, Babatunde O; Miyahara, Kanae; Ohmura, Yuichi; Kurozumi, Akira; Matsushita, Toshi; Ohno, Seiichiro; Kanazawa, Susumu; Asaumi, Junichi

2018-02-01

Readout-segmented echo-planar imaging (RESOLVE) is a multi-shot echo-planar imaging (EPI) modality with k-space segmented in the readout direction. We investigated whether RESOLVE decreases the distortion and artifact in the phase direction and increases the signal-to-noise ratio (SNR) in phantoms image taken with 3-tesla (3T) MRI versus conventional EPI. We used a physiological saline phantom and subtraction mapping and observed that RESOLVE's SNR was higher than EPI's. Using RESOLVE, the combination of a special-purpose coil and a large-loop coil had a higher SNR compared to using only a head/neck coil. RESOLVE's image distortioas less than EPI's. We used a 120 mM polyethylene glycol phantom to examine the phase direction artifact.vThe range where the artifact appeared in the apparent diffusion coefficient (ADC) image was shorter with RESOLVE compared to EPI. We used RESOLVE to take images of a Jurkat cell bio-phantom: the cell-region ADC was 856×10-6mm2/sec and the surrounding physiological saline-region ADC was 2,951×10-6mm2/sec. The combination of RESOLVE and the 3T clinical MRI device reduced image distortion and improved SNR and the identification of accurate ADC values due to the phase direction artifact reduction. This combination is useful for obtaining accurate ADC values of bio-phantoms.

MR cholangiopancreatography. Comparison of images obtained with 1.0 and 1.5 tesla units

International Nuclear Information System (INIS)

Yasui, Masayasu; Ito, Katsuyoshi; Koike, Shinji; Matsunaga, Naofumi

2002-01-01

The purpose of this study was to compare the image quality and visualization obtained in MR cholangiopancreatography (MRCP) using different high-field strength (1.0 vs. 1.5 Tesla) MR units and to assess the effect of field strength on MRCP. This study population included 10 healthy volunteers and 37 patients suspected of having pancreatobiliary diseases. MRCP images were obtained using two MR units with different high-field strengths (1.0 and 1.5 Tesla), with half-Fourier acquisition single-shot turbo spin-echo (HASTE) and rapid acquisition by relaxation enhancement (RARE) sequences. The image quality and visualization of each portion of the pancreatobiliary system were graded and recorded using a four-point scale. Additionally, the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were measured. The SNR and CNR in HASTE sequences acquired with the 1.5 Tesla (T) unit were significantly higher than those acquired with the 1.0 T unit (p=0.001). In qualitative analysis, there were no statistically significant differences in image quality or visualization of the ducts in either HASTE or RARE sequences between 1.0 T and 1.5 T. Our study showed that visual image quality provided by MRCP was equivalent at 1.0 and 1.5 T. (author)

An experimental clinical evaluation of EIT imaging with ℓ1 data and image norms.

Science.gov (United States)

Mamatjan, Yasin; Borsic, Andrea; Gürsoy, Doga; Adler, Andy

2013-09-01

Electrical impedance tomography (EIT) produces an image of internal conductivity distributions in a body from current injection and electrical measurements at surface electrodes. Typically, image reconstruction is formulated using regularized schemes in which ℓ2-norms are used for both data misfit and image prior terms. Such a formulation is computationally convenient, but favours smooth conductivity solutions and is sensitive to outliers. Recent studies highlighted the potential of ℓ1-norm and provided the mathematical basis to improve image quality and robustness of the images to data outliers. In this paper, we (i) extended a primal-dual interior point method (PDIPM) algorithm to 2.5D EIT image reconstruction to solve ℓ1 and mixed ℓ1/ℓ2 formulations efficiently, (ii) evaluated the formulation on clinical and experimental data, and (iii) developed a practical strategy to select hyperparameters using the L-curve which requires minimum user-dependence. The PDIPM algorithm was evaluated using clinical and experimental scenarios on human lung and dog breathing with known electrode errors, which requires a rigorous regularization and causes the failure of reconstruction with an ℓ2-norm solution. The results showed that an ℓ1 solution is not only more robust to unavoidable measurement errors in a clinical setting, but it also provides high contrast resolution on organ boundaries.

Recurrent Clinically Mild Encephalitis/Encephalopathy with a Reversible Splenial Lesion (MERS) on Diffusion Weighted Imaging: A Case Report

Energy Technology Data Exchange (ETDEWEB)

Hong, Jung Yeum; Park, Ji Kang; Kim, Seung Hyoung; Choi, Guk Myung [Jeju National University College of Medicine, Jeju (Korea, Republic of)

2011-05-15

We report serial MR imaging of an 11-year-old boy who had a recurrent episode of clinically mild encephalitis/encephalopathy with a reversible splenial lesion. During the first episode, brain lesions were limited to the corpus callosum. However, for the second episode, the lesions were distributed in the corpus callosum and bilateral deep white matter. No abnormality remained in the follow-up MR images obtained after full recovery.

Clinical PET/CT Atlas: A Casebook of Imaging in Oncology

International Nuclear Information System (INIS)

2015-01-01

Integrated positron emission tomography/computed tomography (PET/CT) has evolved since its introduction into the commercial market more than a decade ago. It is now a key procedure, particularly in oncological imaging. Over the last years in routine clinical service, PET/CT has had a significant impact on diagnosis, treatment planning, staging, therapy, and monitoring of treatment response and has therefore played an important role in the care of cancer patients. The high sensitivity from the PET component and the specificity of the CT component give this hybrid imaging modality the unique characteristics that make PET/CT, even after over 10 years of clinical use, one of the fastest growing imaging modalities worldwide. This publication combines over 90 comprehensive cases covering all major indications of fluorodeoxyglucose (18F-FDG)-PET/CT as well as some cases of clinically relevant special tracers. The cases provide an overview of what the specific disease can look like in PET/CT, the typical pattern of the disease’s spread as well as likely pitfalls and teaching points. This PET/CT Atlas will allow professionals interested in PET/CT imaging to embrace the variety of oncological imaging by providing clinically relevant teaching files on the effectiveness and diagnostic quality of FDG-PET/CT imaging in routine applications

Collagene order of articular cartilage by clinical magnetic resonance images and its age dependency

Energy Technology Data Exchange (ETDEWEB)

Seidel, P.; Gruender, W. [Inst. of Medical Physics and Biophysics, Univ. of Leipzig (Germany)

2005-07-01

The present papers describes a novel method to obtain information on the degree of order of the collagen network of the knee meniscal cartilage by means of a single clinical MRI. Images were obtained from 34 healthy volunteers aged between 6 and 76 years as well as from one patient with clinically-diagnosed arthrosis at the age of 32 and 37 years. A siemens vision (1.5 T) MRT with TR = 750 ms, TE = 50 ms, FoV = 160 mm, and Matrix 512 x 512 was used for this purpose. The MR signal intensities of the cartilage were read out along slices with constant height above the subchondral bone and plotted versus the actual angle to the external magnetic field. The obtained intensity curves were fitted by a model distribution, and the degree of order of the collagen fibers was calculated. For the knee meniscal cartilage, there was an age-dependency of the degree of order and a significant deviation of the volunteer with arthrosis from the normal curve. The results are discussed in view of the arcade model and of a possible use of non-invasive clinical MRT for the detection of early arthrotic changes of cartilage. (orig.)

Clinical advances in cardiovascular magnetic resonace imaging and angiography

NARCIS (Netherlands)

Bosch, van den H.C.M.

2018-01-01

Cardiovascular magnetic resonance imaging is an important noninvasive imaging modality for the diagnosis, clinical work‐up and treatment planning in patients suspected for a wide range of cardiovascular pathology. CMR imaging is accurate and reliable, and provides invaluable information to evaluate

Narrow-Band Imaging: Clinical Application in Gastrointestinal Endoscopy

Directory of Open Access Journals (Sweden)

Sandra Barbeiro

2018-03-01

Full Text Available Narrow-band imaging is an advanced imaging system that applies optic digital methods to enhance endoscopic images and improves visualization of the mucosal surface architecture and microvascular pattern. Narrow-band imaging use has been suggested to be an important adjunctive tool to white-light endoscopy to improve the detection of lesions in the digestive tract. Importantly, it also allows the distinction between benign and malignant lesions, targeting biopsies, prediction of the risk of invasive cancer, delimitation of resection margins, and identification of residual neoplasia in a scar. Thus, in expert hands it is a useful tool that enables the physician to decide on the best treatment (endoscopic or surgical and management. Current evidence suggests that it should be used routinely for patients at increased risk for digestive neoplastic lesions and could become the standard of care in the near future, at least in referral centers. However, adequate training programs to promote the implementation of narrow-band imaging in daily clinical practice are needed. In this review, we summarize the current scientific evidence on the clinical usefulness of narrow-band imaging in the diagnosis and characterization of digestive tract lesions/cancers and describe the available classification systems.

Quantitative imaging biomarkers: the application of advanced image processing and analysis to clinical and preclinical decision making.

Science.gov (United States)

Prescott, Jeffrey William

2013-02-01

The importance of medical imaging for clinical decision making has been steadily increasing over the last four decades. Recently, there has also been an emphasis on medical imaging for preclinical decision making, i.e., for use in pharamaceutical and medical device development. There is also a drive towards quantification of imaging findings by using quantitative imaging biomarkers, which can improve sensitivity, specificity, accuracy and reproducibility of imaged characteristics used for diagnostic and therapeutic decisions. An important component of the discovery, characterization, validation and application of quantitative imaging biomarkers is the extraction of information and meaning from images through image processing and subsequent analysis. However, many advanced image processing and analysis methods are not applied directly to questions of clinical interest, i.e., for diagnostic and therapeutic decision making, which is a consideration that should be closely linked to the development of such algorithms. This article is meant to address these concerns. First, quantitative imaging biomarkers are introduced by providing definitions and concepts. Then, potential applications of advanced image processing and analysis to areas of quantitative imaging biomarker research are described; specifically, research into osteoarthritis (OA), Alzheimer's disease (AD) and cancer is presented. Then, challenges in quantitative imaging biomarker research are discussed. Finally, a conceptual framework for integrating clinical and preclinical considerations into the development of quantitative imaging biomarkers and their computer-assisted methods of extraction is presented.

Clinical findings versus imaging studies in the diagnosis of infantile ...

African Journals Online (AJOL)

Background: Infantile hypertrophic pyloric stenosis is the most common surgical cause of vomiting in early infancy and can be diagnosed clinically or by imaging studies. Objectives: The aim of this study was to assess the accuracy of clinical examination compared with ultrasound and upper gastrointestinal contrast imaging ...

Image-derived input function obtained in a 3TMR-brainPET

Energy Technology Data Exchange (ETDEWEB)

Silva, N.A. da [Institute of Biophysics and Biomedical Engineering, University of Lisbon (Portugal); Institute of Neurosciences and Medicine - 4, Juelich (Germany); Herzog, H., E-mail: h.herzog@fz-juelich.de [Institute of Neurosciences and Medicine - 4, Juelich (Germany); Weirich, C.; Tellmann, L.; Rota Kops, E. [Institute of Neurosciences and Medicine - 4, Juelich (Germany); Hautzel, H. [Department of Nuclear Medicine (KME), University of Duesseldorf, Medical Faculty at Research Center Juelich, Juelich (Germany); Almeida, P. [Institute of Biophysics and Biomedical Engineering, University of Lisbon (Portugal)

2013-02-21

Aim: The combination of a high-resolution MR-compatible BrainPET insert operated within a 3 T MAGNETOM Trio MR scanner is an excellent tool for obtaining an image derived input function (IDIF), due to simultaneous imaging. In this work, we explore the possibility of obtaining an IDIF from volumes of interest (VOI) defined over the carotid arteries (CAs) using the MR data. Material and methods: FDG data from three patients without brain disorders were included. VOIs were drawn bilaterally over the CAs on a MPRAGE image using a 50% isocontour (MR50VOI). CA PET/MR co-registration was examined based on an individual and combined CA co-registration. After that, to estimate the IDIF, the MR50VOI average (IDIF-A), four hottest pixels per plane (IDIF-4H) and four hottest pixels in VOI (IDIF-4V) were considered. A model-based correction for residual partial volume effects involving venous blood samples was applied, from which partial volume (PV) and spillover (SP) coefficients were estimated. Additionally, a theoretical PV coefficient (PVt) was calculated based on MR50VOI. Results: The results show an excellent co-registration between the MR and PET, with an area under the curve ratio between both co-registration methods of 1.00±0.04. A good agreement between PV and PVt was found for IDIF-A, with PV of 0.39±0.06 and PVt 0.40±0.03, and for IDIF-4H, with PV of 0.47±0.05 and PVt 0.47±0.03. The SPs were 0.20±0.03 and 0.21±0.03 for IDIF-A and IDIF-4H, respectively. Conclusion: The integration of a high resolution BrainPET in an MR scanner allows to obtain an IDIF from an MR-based VOI. This must be corrected for a residual partial volume effect.

Development of Methods for Obtaining Position Image and Chemical Binding Information from Flow Experiments of Porous Media

Energy Technology Data Exchange (ETDEWEB)

Haugan, Are

1998-12-01

Existing oil reservoirs might be more fully exploited if the properties of the flow of oil and water in porous media were better known. In laboratory experiments it is important to collect as much information as possible to make a descriptive model of the system, including position imaging and chemical binding information. This thesis develops nuclear methods for obtaining position image and chemical binding information from flow experiments of porous media. A combined positron emission tomography and single photon emission computed tomography system to obtain position images, and a time-differential perturbed angular correlation system to obtain chemical binding information, have been built and thoroughly tested. 68 refs., 123 figs., 14 tabs.

Correlation of the clinical and physical image quality in chest radiography for average adults with a computed radiography imaging system.

Science.gov (United States)

Moore, C S; Wood, T J; Beavis, A W; Saunderson, J R

2013-07-01

The purpose of this study was to examine the correlation between the quality of visually graded patient (clinical) chest images and a quantitative assessment of chest phantom (physical) images acquired with a computed radiography (CR) imaging system. The results of a previously published study, in which four experienced image evaluators graded computer-simulated postero-anterior chest images using a visual grading analysis scoring (VGAS) scheme, were used for the clinical image quality measurement. Contrast-to-noise ratio (CNR) and effective dose efficiency (eDE) were used as physical image quality metrics measured in a uniform chest phantom. Although optimal values of these physical metrics for chest radiography were not derived in this work, their correlation with VGAS in images acquired without an antiscatter grid across the diagnostic range of X-ray tube voltages was determined using Pearson's correlation coefficient. Clinical and physical image quality metrics increased with decreasing tube voltage. Statistically significant correlations between VGAS and CNR (R=0.87, pchest CR images acquired without an antiscatter grid. A statistically significant correlation has been found between the clinical and physical image quality in CR chest imaging. The results support the value of using CNR and eDE in the evaluation of quality in clinical thorax radiography.

Experimental and clinical studies of fast three-dimensional MR imaging of the heart

International Nuclear Information System (INIS)

Sato, Shuhei

1999-01-01

MRI has been utilized since its inception to study the anatomy and physiology of the heart. However, the sensitivity of MRI to motion has always posed a major challenge in imaging this organ. The purpose of this study was to develop a 3D MP-RAGE technique for the heart, and to apply it clinically. In the experimental study, data acquisition timing was discussed by normal volunteers. Changes in magnetization recovery time affected imaging contrast very little in the phantom study. Fourteen adults and 21 children were examined. In the adults, MP-RAGE images were rated as high in quality in the visual estimation. In the quantitative estimation, the images provided almost the same anatomical information as those of cine MRI. In the children, MP-RAGE was useful for cases of partial anomalous pulmonary venous drainage, particularly in the evaluation of abnormal pulmonary veins. The 3D MP-RAGE technique was useful in imaging the heart because it was possible to obtain continuous views in the same cardiac cycle and to reconstruct views from any direction after the examination. (author)

Experimental and clinical studies of fast three-dimensional MR imaging of the heart

Energy Technology Data Exchange (ETDEWEB)

Sato, Shuhei [Okayama Univ. (Japan). School of Medicine

1999-07-01

MRI has been utilized since its inception to study the anatomy and physiology of the heart. However, the sensitivity of MRI to motion has always posed a major challenge in imaging this organ. The purpose of this study was to develop a 3D MP-RAGE technique for the heart, and to apply it clinically. In the experimental study, data acquisition timing was discussed by normal volunteers. Changes in magnetization recovery time affected imaging contrast very little in the phantom study. Fourteen adults and 21 children were examined. In the adults, MP-RAGE images were rated as high in quality in the visual estimation. In the quantitative estimation, the images provided almost the same anatomical information as those of cine MRI. In the children, MP-RAGE was useful for cases of partial anomalous pulmonary venous drainage, particularly in the evaluation of abnormal pulmonary veins. The 3D MP-RAGE technique was useful in imaging the heart because it was possible to obtain continuous views in the same cardiac cycle and to reconstruct views from any direction after the examination. (author)

The clinical impact of a combined gamma camera/CT imaging system on somatostatin receptor imaging of neuroendocrine tumours

International Nuclear Information System (INIS)

Hillel, P.G.; Beek, E.J.R. van; Taylor, C.; Lorenz, E.; Bax, N.D.S.; Prakash, V.; Tindale, W.B.

2006-01-01

AIM: With a combined gamma camera/CT imaging system, CT images are obtained which are inherently registered to the emission images and can be used for the attenuation correction of SPECT and for mapping the functional information from these nuclear medicine tomograms onto anatomy. The aim of this study was to evaluate the clinical impact of SPECT/CT using such a system for somatostatin receptor imaging (SRI) of neuroendocrine tumours. MATERIALS AND METHODS: SPECT/CT imaging with 111 In-Pentetreotide was performed on 29 consecutive patients, the majority of whom had carcinoid disease. All SPECT images were first reported in isolation and then re-reported with the addition of the CT images for functional anatomical mapping (FAM). RESULTS: Fifteen of the 29 SPECT images were reported as abnormal, and in 11 of these abnormal images (73%) FAM was found to either establish a previously unknown location (7/11) or change the location (4/11) of at least one lesion. The revised location could be independently confirmed in 64% of these cases. Confirmation of location was not possible in the other patients due to either a lack of other relevant investigations, or the fact that lesions seen in the SPECT images were not apparent in the other investigations. FAM affected patient management in 64% of the cases where the additional anatomical information caused a change in the reported location of lesions. CONCLUSION: These results imply that FAM can improve the reporting accuracy for SPECT SRI with significant impact on patient management

Fundamentals of functional imaging I: current clinical techniques.

Science.gov (United States)

Luna, A; Martín Noguerol, T; Mata, L Alcalá

2018-05-01

Imaging techniques can establish a structural, physiological, and molecular phenotype for cancer, which helps enable accurate diagnosis and personalized treatment. In recent years, various imaging techniques that make it possible to study the functional characteristics of tumors quantitatively and reproducibly have been introduced and have become established in routine clinical practice. Perfusion studies enable us to estimate the microcirculation as well as tumor angiogenesis and permeability using ultrafast dynamic acquisitions with ultrasound, computed tomography, or magnetic resonance (MR) imaging. Diffusion-weighted sequences now form part of state-of-the-art MR imaging protocols to evaluate oncologic lesions in any anatomic location. Diffusion-weighted imaging provides information about the occupation of the extracellular and extravascular space and indirectly estimates the cellularity and apoptosis of tumors, having demonstrated its relation with biologic aggressiveness in various tumor lines and its usefulness in the evaluation of the early response to systemic and local targeted therapies. Another tool is hydrogen proton MR spectroscopy, which is used mainly in the study of the metabolic characteristics of brain tumors. However, the complexity of the technique and its lack of reproducibility have limited its clinical use in other anatomic areas, although much experience with the use of this technique in the assessment of prostate and breast cancers as well as liver lesions has also accumulated. This review analyzes the imaging techniques that make it possible to evaluate the physiological and molecular characteristics of cancer that have already been introduced into clinical practice, such as techniques that evaluate angiogenesis through dynamic acquisitions after the administration of contrast material, diffusion-weighted imaging, or hydrogen proton MR spectroscopy, as well as their principal applications in oncology. Copyright © 2018 SERAM. Publicado

Interpretation of secondary electron images obtained using a low vacuum SEM

International Nuclear Information System (INIS)

Toth, M.; Thiel, B.L.; Donald, A.M.

2003-01-01

Charging of insulators in a variable pressure environment was investigated in the context of secondary electron (SE) image formation. Sample charging and ionized gas molecules present in a low vacuum specimen chamber can give rise to SE image contrast. 'Charge-induced' SE contrast reflects lateral variations in the charge state of a sample caused by electron irradiation during and prior to image acquisition. This contrast corresponds to SE emission current alterations produced by sub-surface charge deposited by the electron beam. 'Ion-induced' contrast results from spatial inhomogeneities in the extent of SE signal inhibition caused by ions in the gaseous environment of a low vacuum scanning electron microscope (SEM). The inhomogeneities are caused by ion focusing onto regions of a sample that correspond to local minima in the magnitude of the surface potential (generated by sub-surface trapped charge), or topographic asperities. The two types of contrast exhibit characteristic dependencies on microscope operating parameters such as scan speed, beam current, gas pressure, detector bias and working distance. These dependencies, explained in terms of the behavior of the gaseous environment and sample charging, can serve as a basis for a correct interpretation of SE images obtained using a low vacuum SEM

Analysis and clinical usefullness of cardiac ECT images

International Nuclear Information System (INIS)

Hayashi, Makoto; Kagawa, Masaaki; Yamada, Yukinori

1983-01-01

We estimated basically and clinically myocardial ECT image and ECG gated cardiac blood-pool ECT image. ROC curve is used for the evaluation of the accuracy in diagnostic myocardial infarction. The accuracy in diagnostic of MI is superior in myocardial ECT image and ECT estimation is unnecessary skillfulness and experience. We can absene the whole defect of MI than planar image by using ECT. LVEDV between estimated volume and contrast volume is according to it and get one step for automatic analysis of cardiac volume. (author)

Lateral Augmentation Procedures in Anterior Cruciate Ligament Reconstruction: Anatomic, Biomechanical, Imaging, and Clinical Evidence.

Science.gov (United States)

Weber, Alexander E; Zuke, William; Mayer, Erik N; Forsythe, Brian; Getgood, Alan; Verma, Nikhil N; Bach, Bernard R; Bedi, Asheesh; Cole, Brian J

2018-02-01

There has been an increasing interest in lateral-based soft tissue reconstructive techniques as augments to anterior cruciate ligament reconstruction (ACLR). The objective of these procedures is to minimize anterolateral rotational instability of the knee after surgery. Despite the relatively rapid increase in surgical application of these techniques, many clinical questions remain. To provide a comprehensive update on the current state of these lateral-based augmentation procedures by reviewing the origins of the surgical techniques, the biomechanical data to support their use, and the clinical results to date. Systematic review. A systematic search of the literature was conducted via the Medline, EMBASE, Scopus, SportDiscus, and CINAHL databases. The search was designed to encompass the literature on lateral extra-articular tenodesis (LET) procedures and the anterolateral ligament (ALL) reconstruction. Titles and abstracts were reviewed for relevance and sorted into the following categories: anatomy, biomechanics, imaging/diagnostics, surgical techniques, and clinical outcomes. The search identified 4016 articles. After review for relevance, 31, 53, 27, 35, 45, and 78 articles described the anatomy, biomechanics, imaging/diagnostics, surgical techniques, and clinical outcomes of either LET procedures or the ALL reconstruction, respectively. A multitude of investigations were available, revealing controversy in addition to consensus in several categories. The level of evidence obtained from this search was not adequate for systematic review or meta-analysis; thus, a current concepts review of the anatomy, biomechanics, imaging, surgical techniques, and clinical outcomes was performed. Histologically, the ALL appears to be a distinct structure that can be identified with advanced imaging techniques. Biomechanical evidence suggests that the anterolateral structures of the knee, including the ALL, contribute to minimizing anterolateral rotational instability

Quality assurance in ultrasound screening for hepatocellular carcinoma using a standardized phantom and standard clinical images: a 3-year national investigation in Korea.

Science.gov (United States)

Choi, Joon-Il; Jung, Seung Eun; Kim, Pyo Nyun; Cha, Sang Hoon; Jun, Jae Kwan; Lee, Hoo-Yeon; Park, Eun-Cheol

2014-06-01

The purpose of this study was to investigate the quality of ultrasound (US) imaging for hepatocellular carcinoma screening. The investigation was performed at all medical institutes participating in the National Cancer Screening Program in Korea. For assessment of personnel, we inquired who was performing the US screenings. For phantom image evaluation, the dead zone, vertical and horizontal measurements, axial and lateral resolution, sensitivity, and gray scale/dynamic range were evaluated. For clinical image evaluation, US images of patients were evaluated in terms of the standard images, technical information, overall image quality, appropriateness of depth, foci, annotations, and the presence of any artifacts. Failure rates for phantom and clinical image evaluations at general hospitals, smaller hospitals, and private clinics were 20.9%, 24.5%, 24.1% and 5.5%, and 14.8% and 9.5%, respectively. No statistically significant difference was observed in the failure rates for the phantom images among groups of different years of manufacture. For the clinical image evaluation, the results of radiologists were significantly better than those of other professional groups (P = .0001 and .0004 versus nonradiology physicians and nonphysicians, respectively). The failure rate was also higher when the storage format was analog versus digital (P quality of the clinical images obtained by radiologists was the best. © 2014 by the American Institute of Ultrasound in Medicine.

Classified study and clinical value of the phase imaging features

International Nuclear Information System (INIS)

Dang Yaping; Ma Aiqun; Zheng Xiaopu; Yang Aimin; Xiao Jiang; Gao Xinyao

2000-01-01

445 patients with various heart diseases were examined by the gated cardiac blood pool imaging, and the phase was classified. The relationship between the seven types with left ventricular function index, clinical heart function, different heart diseases as well as electrocardiograph was studied. The results showed that the phase image classification could match with the clinical heart function. It can visually, directly and accurately indicate clinical heart function and can be used to identify diagnosis of heart disease

In vitro comparison between the image obtained using PSP plates and Kodak E-speed films.

Science.gov (United States)

Petel, R; Yaroslavsky, L; Kaffe, I

2014-07-01

The aim of this study was to compare the intra-oral radiographic images obtained by a PSP digital radiography system ("Orex", Israel) with that obtained using Kodak Ultra speed films in terms of image quality, radiation dosage and diagnostic value. The physical measurement of image quality was conducted with an aluminum step-wedge. Radiation dosage was measured with a dosimeter. Fog and base levels were measured by developing unexposed films and scanning unexposed PSP plates. The in vitro model included preparation and radiographic evaluation of approximal artificial lesions in premolars and molars in depths ranging from 0.25 mm to 1.00 mm. Radiographs were evaluated for the existence of a lesion and its size by 8 experienced clinicians. Relative contrast was similar in both methods. The resolving power of the digital system was lower than that of the E-speed film. As for the subjective evaluation of artificial lesions, there was no significant difference between the two methods excluding those tooth images without lesions, where the analog method was found to be more accurate. The PSP system ("Orex") provides good image quality and diagnostic information with reduced exposure when compared with E-speed film.

First MR images obtained during megavoltage photon irradiation from a prototype integrated linac-MR system

International Nuclear Information System (INIS)

Fallone, B. G.; Murray, B.; Rathee, S.; Stanescu, T.; Steciw, S.; Vidakovic, S.; Blosser, E.; Tymofichuk, D.

2009-01-01

The authors report the first magnetic resonance (MR) images produced by their prototype MR system integrated with a radiation therapy source. The prototype consists of a 6 MV linac mounted onto the open end of a biplanar 0.2 T permanent MR system which has 27.9 cm pole-to-pole opening with flat gradients (40 mT/m) running under a TMX NRC console. The distance from the magnet isocenter to the linac target is 80 cm. The authors' design has resolved the mutual interferences between the two devices such that the MR magnetic field does not interfere with the trajectory of the electron in the linac waveguide, and the radiofrequency (RF) signals from each system do not interfere with the operation of the other system. Magnetic and RF shielding calculations were performed and confirmed with appropriate measurements. The prototype is currently on a fixed gantry; however, in the very near future, the linac and MR magnet will rotate in unison such that the linac is always aimed through the opening in the biplanar magnet. MR imaging was found to be fully operational during linac irradiation and proven by imaging a phantom with conventional gradient echo sequences. Except for small changes in SNR, MR images produced during irradiation were visually and quantitatively very similar to those taken with the linac turned off. This prototype system provides proof of concept that the design has decreased the mutual interferences sufficiently to allow the development of real-time MR-guided radiotherapy. Low field-strength systems (0.2-0.5 T) have been used clinically as diagnostic tools. The task of the linac-MR system is, however, to provide MR guidance to the radiotherapy beam. Therefore, the 0.2 T field strength would provide adequate image quality for this purpose and, with the addition of fast imaging techniques, has the potential to provide 4D soft-tissue visualization not presently available in image-guided radiotherapy systems. The authors' initial design incorporates a

Malignant fatty tumors: classification, clinical course, imaging appearance and treatment

International Nuclear Information System (INIS)

Peterson, J.J.; Kransdorf, M.J.; Bancroft, L.W.; O'Connor, M.I.

2003-01-01

Liposarcoma is a relatively common soft tissue malignancy with a wide spectrum of clinical presentations and imaging appearances. Several subtypes are described, ranging from lesions nearly entirely composed of mature adipose tissue, to tumors with very sparse adipose elements. The imaging appearance of these fatty masses is frequently sufficiently characteristic to allow a specific diagnosis, while in other cases, although a specific diagnosis is not achievable, a meaningful limited differential diagnosis can be established. The purpose of this paper is to review the spectrum of malignant fatty tumors, highlighting the current classification system, clinical presentation and behavior, treatment and spectrum of imaging appearances. The imaging review will emphasize CT scanning and MR imaging, and will stress differentiating radiologic features. (orig.)

Benign fatty tumors: classification, clinical course, imaging appearance, and treatment

International Nuclear Information System (INIS)

Bancroft, Laura W.; Kransdorf, Mark J.; Peterson, Jeffrey J.; O'Connor, Mary I.

2006-01-01

Lipoma is the most common soft-tissue tumor, with a wide spectrum of clinical presentations and imaging appearances. Several subtypes are described, ranging from lesions entirely composed of mature adipose tissue to tumors intimately associated with nonadipose tissue, to those composed of brown fat. The imaging appearance of these fatty masses is frequently sufficiently characteristic to allow a specific diagnosis. However, in other cases, although a specific diagnosis is not achievable, a meaningful limited differential diagnosis can be established. The purpose of this manuscript is to review the spectrum of benign fatty tumors highlighting the current classification system, clinical presentation and behavior, spectrum of imaging appearances, and treatment. The imaging review emphasizes computed tomography (CT) scanning and magnetic resonance (MR) imaging, differentiating radiologic features. (orig.)

A program for phase identification using diffractograms obtained from Tem structure images

Energy Technology Data Exchange (ETDEWEB)

Galicia, R.; Herrera, R.; Rius, J. L.; Zorrilla, C.; Gomez, A., E-mail: rherrera@fisica.unam.mx [UNAM, Instituto de Fisica, Apdo. Postal 20-364, 01000 Mexico D. F. (Mexico)

2013-05-01

In this work a computer program for the indexing of diffractograms is presented. The diffractograms are obtained by means of a discrete Fourier transform from high resolution electron microscope images. The program requires the use of X-ray diffraction data files together with a fast Fourier transform program, for this purpose we used the Digital Micrograph software. (Author)

Multilocular cystic renal cell carcinoma: imaging and clinical correlation

International Nuclear Information System (INIS)

Xu Yong; Zhang Sheng

2013-01-01

Multilocular cystic renal cell carcinoma (MCRCC) is a subtype of clear cell renal cell carcinoma and has mild clinical symptoms and a favorable prognosis. Accordingly, nephron-sparing surgery is recommended as a therapeutic strategy. If histologic subtype of MCRCC can be predicted preoperatively with an acceptable level of accuracy, it may be important in predicting prognosis and make clinical management. Most MCRCCs show characteristic cross-sectional imaging findings and permit accurate diagnosis before the treatment. Cross -sectional imaging of MCRCC reveals a well -defined multilocular cystic mass with irregularly enhanced thickened septa and without enhanced intracystic solid nodule. It is often classified as Bosniak classification Ⅲ , which is significantly different from that of other renal cystic masses. The clinical, pathologic, and radiologic features of MCRCC were discussed and illustrated in this article. The role of the imaging preoperative evaluation for MCRCC, and management implications were emphasized. (authors)

High-resolution MR imaging of the elbow using a microscopy surface coil and a clinical 1.5 T MR machine: preliminary results

International Nuclear Information System (INIS)

Yoshioka, Hiroshi; Ueno, Teruko; Takahashi, Nobuyuki; Saida, Yukihisa; Tanaka, Toshikazu; Kujiraoka, Yuka; Shindo, Masashi; Nishiura, Yasumasa; Ochiai, Naoyuki

2004-01-01

To obtain high-resolution MR images of the elbow using a microscopy surface coil with a 1.5 T clinical machine and to evaluate the feasibility of its use for elbow injuries. Five asymptomatic normal volunteers and 13 patients with elbow pain were prospectively studied with MR imaging using a microscopy surface coil 47 mm in diameter. High-resolution MR images using a microscopy coil were obtained with fast spin echo (FSE) proton density-weighted sequence, gradient recalled echo (GRE) T2*-weighted sequence, and short tau inversion recovery (STIR) sequence, with a 1-2 mm slice thickness, a 50-70 mm field of view, an imaging matrix of 140-224 x 512 using zero fill interpolation, and 2-6 excitations. High-resolution MR images of normal volunteers using a microscopy coil clearly showed each structure of the medial and lateral collateral ligaments on GRE T2*-weighted images and FSE proton-density weighted images. Partial medial collateral ligament injury, a small avulsion of the medial epicondyle, and osteochondritis dissecans were well demonstrated on high-resolution MR images. High-resolution MR imaging of the elbow using a microscopy surface coil with a 1.5 T clinical machine is a promising method for accurately characterizing the normal anatomy of the elbow and depicting its lesions in detail. (orig.)

Comparison of clinical and physics scoring of PET images when image reconstruction parameters are varied

International Nuclear Information System (INIS)

Walsh, C.; Johnston, C.; Sheehy, N.; Reilly, G. O.

2013-01-01

In this study the quantitative and qualitative image quality (IQ) measurements with clinical judgement of IQ in positron emission tomography (PET) were compared. The limitations of IQ metrics and the proposed criteria of acceptability for PET scanners are discussed. Phantom and patient images were reconstructed using seven different iterative reconstruction protocols. For each reconstructed set of images, IQ was scored based both on the visual analysis and on the quantitative metrics. The quantitative physics metrics did not rank the reconstruction protocols in the same order as the clinicians' scoring of perceived IQ (R s = -0.54). Better agreement was achieved when comparing the clinical perception of IQ to the physicist's visual assessment of IQ in the phantom images (R s = +0.59). The closest agreement was seen between the quantitative physics metrics and the measurement of the standard uptake values (SUVs) in small tumours (R s = +0.92). Given the disparity between the clinical perception of IQ and the physics metrics a cautious approach to use of IQ measurements for determining suspension levels is warranted. (authors)

Evaluation of web-based annotation of ophthalmic images for multicentric clinical trials.

Science.gov (United States)

Chalam, K V; Jain, P; Shah, V A; Shah, Gaurav Y

2006-06-01

An Internet browser-based annotation system can be used to identify and describe features in digitalized retinal images, in multicentric clinical trials, in real time. In this web-based annotation system, the user employs a mouse to draw and create annotations on a transparent layer, that encapsulates the observations and interpretations of a specific image. Multiple annotation layers may be overlaid on a single image. These layers may correspond to annotations by different users on the same image or annotations of a temporal sequence of images of a disease process, over a period of time. In addition, geometrical properties of annotated figures may be computed and measured. The annotations are stored in a central repository database on a server, which can be retrieved by multiple users in real time. This system facilitates objective evaluation of digital images and comparison of double-blind readings of digital photographs, with an identifiable audit trail. Annotation of ophthalmic images allowed clinically feasible and useful interpretation to track properties of an area of fundus pathology. This provided an objective method to monitor properties of pathologies over time, an essential component of multicentric clinical trials. The annotation system also allowed users to view stereoscopic images that are stereo pairs. This web-based annotation system is useful and valuable in monitoring patient care, in multicentric clinical trials, telemedicine, teaching and routine clinical settings.

Review of SPECT collimator selection, optimization, and fabrication for clinical and preclinical imaging

Energy Technology Data Exchange (ETDEWEB)

Van Audenhaege, Karen, E-mail: karen.vanaudenhaege@ugent.be; Van Holen, Roel; Vandenberghe, Stefaan; Vanhove, Christian [Department of Electronics and Information Systems, MEDISIP-IBiTech, Ghent University–iMinds Medical IT, De Pintelaan 185 block B/5, Ghent B-9000 (Belgium); Metzler, Scott D. [Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Moore, Stephen C. [Division of Nuclear Medicine, Department of Radiology, Brigham and Women’s Hospital and Harvard Medical School, 75 Francis Street, Boston, Massachusetts 02115 (United States)

2015-08-15

In single photon emission computed tomography, the choice of the collimator has a major impact on the sensitivity and resolution of the system. Traditional parallel-hole and fan-beam collimators used in clinical practice, for example, have a relatively poor sensitivity and subcentimeter spatial resolution, while in small-animal imaging, pinhole collimators are used to obtain submillimeter resolution and multiple pinholes are often combined to increase sensitivity. This paper reviews methods for production, sensitivity maximization, and task-based optimization of collimation for both clinical and preclinical imaging applications. New opportunities for improved collimation are now arising primarily because of (i) new collimator-production techniques and (ii) detectors with improved intrinsic spatial resolution that have recently become available. These new technologies are expected to impact the design of collimators in the future. The authors also discuss concepts like septal penetration, high-resolution applications, multiplexing, sampling completeness, and adaptive systems, and the authors conclude with an example of an optimization study for a parallel-hole, fan-beam, cone-beam, and multiple-pinhole collimator for different applications.

2-D images of the metal-halide lamp obtained by experiment and model

NARCIS (Netherlands)

Flikweert, A.J.; Beks, M.L.; Nimalasuriya, T.; Kroesen, G.M.W.; Mullen, van der J.J.A.M.; Stoffels, W.W.

2008-01-01

The metal-halide lamp shows color segregation caused by diffusion and convection. Two-dimensional imaging of the arc discharge under varying gravity conditions aids in the understanding of the flow phenomena. In this paper, we show results obtained by experiments and by numerical simulations in

Clinical perspectives of hybrid proton-fluorine magnetic resonance imaging and spectroscopy.

Science.gov (United States)

Wolters, Martijn; Mohades, Seyede G; Hackeng, Tilman M; Post, Mark J; Kooi, Marianne E; Backes, Walter H

2013-05-01

The number of applications of fluorine 19 (19F) magnetic resonance (MR) imaging and spectroscopy in biomedical and clinical research is steadily growing. The 100% natural abundance of fluorine and its relatively high sensitivity for MR (83% to that of protons) make it an interesting nucleus for a wide range of MR applications. Fluorinated contrast media have a number of advantages over the conventionally used gadolinium-based or iron-based contrast agents. The absence of an endogenous fluorine background intensity in the human body facilitates reliable quantification of fluorinated contrast medium or drugs. Anatomy can be visualized separately with proton MR imaging, creating the application of hybrid hydrogen 1 (1H)/19F MR imaging. The availability of 2 channels (ie, the 1H and 19F channels) enables dual-targeted molecular imaging. Recently, novel developments have emerged on fluorine-based contrast media in preclinical studies and imaging techniques. The developments in fluorine MR seem promising for clinical applications, with contributions in therapy monitoring, assessment of lung function, angiography, and molecular imaging. This review outlines the translation from recent advances in preclinical MR imaging and spectroscopy to future perspectives of clinical hybrid 1H/19/F MR imaging applications.

Medical imaging in clinical applications algorithmic and computer-based approaches

CERN Document Server

Bhateja, Vikrant; Hassanien, Aboul

2016-01-01

This volume comprises of 21 selected chapters, including two overview chapters devoted to abdominal imaging in clinical applications supported computer aided diagnosis approaches as well as different techniques for solving the pectoral muscle extraction problem in the preprocessing part of the CAD systems for detecting breast cancer in its early stage using digital mammograms. The aim of this book is to stimulate further research in medical imaging applications based algorithmic and computer based approaches and utilize them in real-world clinical applications. The book is divided into four parts, Part-I: Clinical Applications of Medical Imaging, Part-II: Classification and clustering, Part-III: Computer Aided Diagnosis (CAD) Tools and Case Studies and Part-IV: Bio-inspiring based Computer Aided diagnosis techniques. .

Intensity correction method customized for multi-animal abdominal MR imaging with 3 T clinical scanner and multi-array coil

International Nuclear Information System (INIS)

Mitsuda, Minoru; Yamaguchi, Masayuki; Nakagami, Ryutaro; Furuta, Toshihiro; Fujii, Hirofumi; Sekine, Norio; Niitsu, Mamoru; Moriyama, Noriyuki

2013-01-01

Simultaneous magnetic resonance (MR) imaging of multiple small animals in a single session increases throughput of preclinical imaging experiments. Such imaging using a 3-tesla clinical scanner with multi-array coil requires correction of intensity variation caused by the inhomogeneous sensitivity profile of the coil. We explored a method for correcting intensity that we customized for multi-animal MR imaging, especially abdominal imaging. Our institutional committee for animal experimentation approved the protocol. We acquired high resolution T 1 -, T 2 -, and T 2 * -weighted images and low resolution proton density-weighted images (PDWIs) of 4 rat abdomens simultaneously using a 3T clinical scanner and custom-made multi-array coil. For comparison, we also acquired T 1 -, T 2 -, and T 2 * -weighted volume coil images in the same rats in 4 separate sessions. We used software created in-house to correct intensity variation. We applied thresholding to the PDWIs to produce binary images that displayed only a signal-producing area, calculated multi-array coil sensitivity maps by dividing low-pass filtered PDWIs by low-pass filtered binary images pixel by pixel, and divided uncorrected T 1 -, T 2 -, or T 2 * -weighted images by those maps to obtain intensity-corrected images. We compared tissue contrast among the liver, spinal canal, and muscle between intensity-corrected multi-array coil images and volume coil images. Our intensity correction method performed well for all pulse sequences studied and corrected variation in original multi-array coil images without deteriorating the throughput of animal experiments. Tissue contrasts were comparable between intensity-corrected multi-array coil images and volume coil images. Our intensity correction method customized for multi-animal abdominal MR imaging using a 3T clinical scanner and dedicated multi-array coil could facilitate image interpretation. (author)

Functional imaging of the pancreas. Image processing techniques and clinical evaluation

Energy Technology Data Exchange (ETDEWEB)

Nakanishi, Fumiko

1984-02-01

An image processing technique for functional imaging of the pancreas was developed and is here reported. In this paper, clinical efficacy of the technique for detecting pancreatic abnormality is evaluated in comparison with conventional pancreatic scintigraphy and CT. For quantitative evaluation, functional rate, i.e. the rate of normal functioning pancreatic area, was calculated from the functional image and subtraction image. Two hundred and ninety-five cases were studied using this technique. Conventional image had a sensitivity of 65% and a specificity of 78%, while the use of functional imaging improved sensitivity to 88% and specificity to 88%. The mean functional rate in patients with pancreatic disease was significantly lower (33.3 +- 24.5 in patients with chronic pancreatitis, 28.1 +- 26.9 in patients with acute pancreatitis, 43.4 +- 22.3 in patients with diabetes mellitus, 20.4 +- 23.4 in patients with pancreatic cancer) than the mean functional rate in cases without pancreatic disease (86.4 +- 14.2). It is suggested that functional image of the pancreas reflecting pancreatic exocrine function and functional rate is a useful indicator of pancreatic exocrine function.

Establishment of quality assessment standard for mammographic equipment: evaluation of phantom and clinical images

International Nuclear Information System (INIS)

Lee, Sung Hoon; Choe, Yeon Hyeon; Chung, Soo Young

2005-01-01

The purpose of this study was to establish a quality standard for mammographic equipment Korea and to eventually improve mammographic quality in clinics and hospitals throughout Korea by educating technicians and clinic personnel. For the phantom test and on site assessment, we visited 37 sites and examined 43 sets of mammographic equipment. Items that were examined include phantom test, radiation dose measurement, developer assessment, etc. The phantom images were assessed visually and by optical density measurements. For the clinical image assessment, clinical images from 371 sites were examined following the new Korean standard for clinical image evaluation. The items examined include labeling, positioning, contrast, exposure, artifacts, collimation among others. Quality standard of mammographic equipment was satisfied in all equipment on site visits. Average mean glandular dose was 114.9 mRad. All phantom image test scores were over 10 points (average, 10.8 points). However, optical density measurements were below 1.2 in 9 sets of equipment (20.9%). Clinical image evaluation revealed appropriate image quality in 83.5%, while images from non-radiologist clinics were adequate in 74.6% (91/122), which was the lowest score of any group. Images were satisfactory in 59.0% (219/371) based on evaluation by specialists following the new Korean standard for clinical image evaluation. Satisfactory images had a mean score of 81.7 (1 S.D. =8.9) and unsatisfactory images had a mean score of 61.9 (1 S.D = 11). The correlation coefficient between the two observers was 0.93 (ρ < 0.01) in 49 consecutive cases. The results of the phantom tests suggest that optical density measurements should be performed as part of a new quality standard for mammographic equipment. The new clinical evaluation criteria that was used in this study can be implemented with some modifications for future mammography quality control by the Korean government

Thymic hyperplasia - clinical course and imaging diagnostic

International Nuclear Information System (INIS)

Drebov, R.; Panov, M.; Totev, M.; Deliverski, T.; Tcandev, I.; Velkovski, I.

2006-01-01

The real thymic hyperplasia is benign disease sometimes simulating malignant tumours. The aim of this study is to analyse the clinical symptoms of real thymic hyperplasia and the results from imaging diagnostic based on our clinical material. Clinical material include 27 children, aged from two months to 15 years, admitted in department of thoracic surgery, for a period of 20 years (1985 - 2004). We retrospectively analyze the clinical signs and results from X-ray investigation, CT (Siemens Somatom DRG and Philips Secura) and echocardiography (Acuson TX, 5 and 7 MHz). We discuss the diagnostic value of different methods as well as typical and atypical findings. (authors)

Magnetic resonance imaging for clinical management of rectal cancer

DEFF Research Database (Denmark)

Beets-Tan, Regina G H; Lambregts, Doenja M J; Maas, Monique

2018-01-01

OBJECTIVES: To update the 2012 ESGAR consensus guidelines on the acquisition, interpretation and reporting of magnetic resonance imaging (MRI) for clinical staging and restaging of rectal cancer. METHODS: Fourteen abdominal imaging experts from the European Society of Gastrointestinal and Abdomin...

Cerebral amyloid angiopathy-related inflammation: imaging findings and clinical outcome

Energy Technology Data Exchange (ETDEWEB)

Martucci, Matia [Vall d' Hebron University Hospital, Neuroradiology Unit, Radiology Department (IDI), Barcelona (Spain); Catholic University of Sacred Heart, ' ' A. Gemelli' ' University Hospital, Department of Radiological Sciences, Rome (Italy); Sarria, Silvana; Coscojuela, Pilar; Vert, Carla; Siurana, Sahyly; Auger, Cristina; Rovira, Alex [Vall d' Hebron University Hospital, Neuroradiology Unit, Radiology Department (IDI), Barcelona (Spain); Toledo, Manuel [Vall d' Hebron University Hospital, Epilepsy Unit, Neurology Department, Barcelona (Spain)

2014-04-15

We aim to investigate the clinical onset, computed tomography (CT) and magnetic resonance (MR) imaging findings, and follow-up of patients with cerebral amyloid angiopathy (CAA)-related inflammation, an uncommon but clinically striking presentation of CAA. We retrospectively reviewed the clinical manifestations, CT/MR imaging findings, and outcome of ten consecutive patients with CAA-related inflammation. In each patient, a brain CT study was performed at hospital admission, and brain MR imaging was carried out 2 to 4 days later. Clinical and radiologic follow-up findings were evaluated in all patients. The most common clinical onset was rapidly progressive cognitive decline, followed by focal neurological signs. Brain CT/MR showed unenhanced expansive subcortical lesions, corresponding to areas of vasogenic edema, associated with chronic lobar, cortical, or cortical-subcortical micro/macrohemorrhages. Clinical symptoms recovered in a few weeks under treatment in eight patients and spontaneously in the remaining two. MRI follow-up at 2 to 12 months after treatment showed resolution of the lesions. Three patients experienced symptomatic disease recurrence, with new lesions on CT/MR. In the absence of histological data, early recognition of the clinical symptoms and typical radiologic features of CAA-related inflammation is essential to enable timely establishment of proper treatment. (orig.)

Cerebral amyloid angiopathy-related inflammation: imaging findings and clinical outcome

International Nuclear Information System (INIS)

Martucci, Matia; Sarria, Silvana; Coscojuela, Pilar; Vert, Carla; Siurana, Sahyly; Auger, Cristina; Rovira, Alex; Toledo, Manuel

2014-01-01

We aim to investigate the clinical onset, computed tomography (CT) and magnetic resonance (MR) imaging findings, and follow-up of patients with cerebral amyloid angiopathy (CAA)-related inflammation, an uncommon but clinically striking presentation of CAA. We retrospectively reviewed the clinical manifestations, CT/MR imaging findings, and outcome of ten consecutive patients with CAA-related inflammation. In each patient, a brain CT study was performed at hospital admission, and brain MR imaging was carried out 2 to 4 days later. Clinical and radiologic follow-up findings were evaluated in all patients. The most common clinical onset was rapidly progressive cognitive decline, followed by focal neurological signs. Brain CT/MR showed unenhanced expansive subcortical lesions, corresponding to areas of vasogenic edema, associated with chronic lobar, cortical, or cortical-subcortical micro/macrohemorrhages. Clinical symptoms recovered in a few weeks under treatment in eight patients and spontaneously in the remaining two. MRI follow-up at 2 to 12 months after treatment showed resolution of the lesions. Three patients experienced symptomatic disease recurrence, with new lesions on CT/MR. In the absence of histological data, early recognition of the clinical symptoms and typical radiologic features of CAA-related inflammation is essential to enable timely establishment of proper treatment. (orig.)

TU-CD-207-03: Time Evolution of Texture Parameters of Subtracted Images Obtained by Contrast-Enhanced Digital Mammography (CEDM)

Energy Technology Data Exchange (ETDEWEB)

Mateos, M-J; Brandan, M-E [Instituto de Fisica, Universidad Nacional Autonom de Mexico, Mexico, Distrito Federal (Mexico); Gastelum, A; Marquez, J [Centro de Ciencias Aplicadas y Desarrollo Tecnologico Universidad Nacional Autonoma de Mexico, Mexico, Distrito Federal (Mexico)

2015-06-15

Purpose: To evaluate the time evolution of texture parameters, based on the gray level co-occurrence matrix (GLCM), in subtracted images of 17 patients (10 malignant and 7 benign) subjected to contrast-enhanced digital mammography (CEDM). The goal is to determine the sensitivity of texture to iodine uptake at the lesion, and its correlation (or lack of) with mean-pixel-value (MPV). Methods: Acquisition of clinical images followed a single-energy CEDM protocol using Rh/Rh/48 kV plus external 0.5 cm Al from a Senographe DS unit. Prior to the iodine-based contrast medium (CM) administration a mask image was acquired; four CM images were obtained 1, 2, 3, and 5 minutes after CM injection. Temporal series were obtained by logarithmic subtraction of registered CM minus mask images.Regions of interest (ROI) for the lesion were drawn by a radiologist and the texture was analyzed. GLCM was evaluated at a 3 pixel distance, 0° angle, and 64 gray-levels. Pixels identified as registration errors were excluded from the computation. 17 texture parameters were chosen, classified according to similarity into 7 groups, and analyzed. Results: In all cases the texture parameters within a group have similar dynamic behavior. Two texture groups (associated to cluster and sum mean) show a strong correlation with MPV; their average correlation coefficient (ACC) is r{sup 2}=0.90. Other two groups (contrast, homogeneity) remain constant with time, that is, a low-sensitivity to CM uptake. Three groups (regularity, lacunarity and diagonal moment) are sensitive to CM uptake but less correlated with MPV; their ACC is r{sup 2}=0.78. Conclusion: This analysis has shown that, at least groups associated to regularity, lacunarity and diagonal moment offer dynamical information additional to the mean pixel value due to the presence of CM at the lesion. The next step will be the analysis in terms of the lesion pathology. Authors thank PAPIIT-IN105813 for support. Consejo Nacional de Ciencia Y

SU-E-I-53: Variation in Measurements of Breast Skin Thickness Obtained Using Different Imaging Modalities

International Nuclear Information System (INIS)

Nguyen, U; Kumaraswamy, N; Markey, M

2014-01-01

Purpose: To investigate variation in measurements of breast skin thickness obtained using different imaging modalities, including mammography, computed tomography (CT), ultrasound, and magnetic resonance imaging (MRI). Methods: Breast skin thicknesses as measured by mammography, CT, ultrasound, and MRI were compared. Mammographic measurements of skin thickness were obtained from published studies that utilized standard positioning (upright) and compression. CT measurements of skin thickness were obtained from a published study of a prototype breast CT scanner in which the women were in the prone position and the breast was uncompressed. Dermatological ultrasound exams of the breast skin were conducted at our institution, with the subjects in the upright position and the breast uncompressed. Breast skin thickness was calculated from breast MRI exams at our institution, with the patient in the prone position and the breast uncompressed. Results: T tests for independent samples demonstrated significant differences in the mean breast skin thickness as measured by different imaging modalities. Repeated measures ANOVA revealed significant differences in breast skin thickness across different quadrants of the breast for some modalities. Conclusion: The measurement of breast skin thickness is significantly different across different imaging modalities. Differences in the amount of compression and differences in patient positioning are possible reasons why measurements of breast skin thickness vary by modality

High-resolution imaging of coronary calcifications by intense low-energy fluoroscopic X-ray obtained from synchrotron radiation

Energy Technology Data Exchange (ETDEWEB)

Ohtsuka, S.; Sugishita, Y.; Takeda, T.; Itai, Y.; Tada, J.; Hyodo, K.; Ando, M. [Inst. of Clinical Medicine, Univ. of Tsukuba, Ibaraki (Japan). Dept. of Cardiology

2000-07-01

In order to obtain an intense monochromatic low-energy X-ray from synchrotron radiation (SR) and apply it to detect coronary calcifications, the SR beam was reflected with a silicon crystal to be expanded (150 mm in height and 80 mm in width) and to be monochromatized at an energy level of 37 keV. The X-ray was intermittently irradiated to obtain dynamic imaging of 30 images/s. Images were recorded by a digital fluorography system. The low-energy X-ray from SR sharply visualized calcification of coronary arteries, while conventional X-ray could not visualize coronary calcification. The intense monochromatic low-energy X-ray from SR is sensitive, has high-resolution for imaging coronary calcification and may serve as a screening method for coronary artery disease.

Preliminary Experience with Small Animal SPECT Imaging on Clinical Gamma Cameras

Directory of Open Access Journals (Sweden)

P. Aguiar

2014-01-01

Full Text Available The traditional lack of techniques suitable for in vivo imaging has induced a great interest in molecular imaging for preclinical research. Nevertheless, its use spreads slowly due to the difficulties in justifying the high cost of the current dedicated preclinical scanners. An alternative for lowering the costs is to repurpose old clinical gamma cameras to be used for preclinical imaging. In this paper we assess the performance of a portable device, that is, working coupled to a single-head clinical gamma camera, and we present our preliminary experience in several small animal applications. Our findings, based on phantom experiments and animal studies, provided an image quality, in terms of contrast-noise trade-off, comparable to dedicated preclinical pinhole-based scanners. We feel that our portable device offers an opportunity for recycling the widespread availability of clinical gamma cameras in nuclear medicine departments to be used in small animal SPECT imaging and we hope that it can contribute to spreading the use of preclinical imaging within institutions on tight budgets.

Image processing of integrated video image obtained with a charged-particle imaging video monitor system

International Nuclear Information System (INIS)

Iida, Takao; Nakajima, Takehiro

1988-01-01

A new type of charged-particle imaging video monitor system was constructed for video imaging of the distributions of alpha-emitting and low-energy beta-emitting nuclides. The system can display not only the scintillation image due to radiation on the video monitor but also the integrated video image becoming gradually clearer on another video monitor. The distortion of the image is about 5% and the spatial resolution is about 2 line pairs (lp)mm -1 . The integrated image is transferred to a personal computer and image processing is performed qualitatively and quantitatively. (author)

Companion diagnostics and molecular imaging-enhanced approaches for oncology clinical trials.

Science.gov (United States)

Van Heertum, Ronald L; Scarimbolo, Robert; Ford, Robert; Berdougo, Eli; O'Neal, Michael

2015-01-01

In the era of personalized medicine, diagnostic approaches are helping pharmaceutical and biotechnology sponsors streamline the clinical trial process. Molecular assays and diagnostic imaging are routinely being used to stratify patients for treatment, monitor disease, and provide reliable early clinical phase assessments. The importance of diagnostic approaches in drug development is highlighted by the rapidly expanding global cancer diagnostics market and the emergent attention of regulatory agencies worldwide, who are beginning to offer more structured platforms and guidance for this area. In this paper, we highlight the key benefits of using companion diagnostics and diagnostic imaging with a focus on oncology clinical trials. Nuclear imaging using widely available radiopharmaceuticals in conjunction with molecular imaging of oncology targets has opened the door to more accurate disease assessment and the modernization of standard criteria for the evaluation, staging, and treatment responses of cancer patients. Furthermore, the introduction and validation of quantitative molecular imaging continues to drive and optimize the field of oncology diagnostics. Given their pivotal role in disease assessment and treatment, the validation and commercialization of diagnostic tools will continue to advance oncology clinical trials, support new oncology drugs, and promote better patient outcomes.

A system dedicated to the viewing and handling of tomographic images obtained by magnetic resonance

International Nuclear Information System (INIS)

Slaets, Joan F.W.; Almeida, Lirio O.B.; Traina, Agma J.M.

1992-01-01

The present work describes the development of a dedicated system to be used in visualization and manipulation of a MR images. The graphics environment as well as the tool kit were developed for the dedicated TMS34010 based hardware. The developed software offers a compact kernel with primitives to support the creation and manipulation windows and menus directly in 'C' language. This work is fundamental for the implementation of a user friendly interface build to operate and visualize tomographic images. This tools are essential for the selection an archiving of images planes as used in clinical applications. (author)

Obtaining patient test results from clinical laboratories: a survey of state law for pharmacists.

Science.gov (United States)

Witry, Matthew J; Doucette, William R

2009-01-01

To identify states with laws that restrict to whom clinical laboratories may release copies of laboratory test results and to describe how these laws may affect pharmacists' ability to obtain patient laboratory test results. Researchers examined state statutes and administrative codes for all 50 states and the District of Columbia at the University of Iowa Law Library between June and July 2007. Researchers also consulted with lawyers, state Clinical Laboratory Improvement Amendments officers, and law librarians. Laws relating to the study objective were analyzed. 34 jurisdictions do not restrict the release of laboratory test results, while 17 states have laws that restrict to whom clinical laboratories can send copies of test results. In these states, pharmacists will have to use alternative sources, such as physician offices, to obtain test results. Pharmacists must consider state law before requesting copies of laboratory test results from clinical laboratories. This may be an issue that state pharmacy associations can address to increase pharmacist access to important patient information.

CT of jejunal diverticulitis: imaging findings, differential diagnosis, and clinical management

International Nuclear Information System (INIS)

Macari, M.; Faust, M.; Liang, H.; Pachter, H.L.

2007-01-01

Aim: To describe the imaging findings of jejunal diverticulitis as depicted at contrast-enhanced computed tomography (CT) and review the differential diagnosis and clinical management. Materials and Methods: CT and pathology databases were searched for the diagnosis of jejunal diverticulitis. Three cases were identified and the imaging and clinical findings correlated. Results: Jejunal diverticulitis presents as a focal inflammatory mass involving the proximal small bowel. A trial of medical management with antibiotics may be attempted. Surgical resection may be required if medical management is unsuccessful. Conclusion: The imaging findings at MDCT may allow a specific diagnosis of jejunal diverticulitis to be considered and may affect the clinical management of the patient

Normal feline brain: clinical anatomy using magnetic resonance imaging.

Science.gov (United States)

Mogicato, G; Conchou, F; Layssol-Lamour, C; Raharison, F; Sautet, J

2012-04-01

The purpose of this study was to provide a clinical anatomy atlas of the feline brain using magnetic resonance imaging (MRI). Brains of twelve normal cats were imaged using a 1.5 T magnetic resonance unit and an inversion/recovery sequence (T1). Fourteen relevant MRI sections were chosen in transverse, dorsal, median and sagittal planes. Anatomic structures were identified and labelled using anatomical texts and Nomina Anatomica Veterinaria, sectioned specimen heads, and previously published articles. The MRI sections were stained according to the major embryological and anatomical subdivisions of the brain. The relevant anatomical structures seen on MRI will assist clinicians to better understand MR images and to relate this neuro-anatomy to clinical signs. © 2011 Blackwell Verlag GmbH.

The introduction of clinical magnetic resonance imaging in Australia

International Nuclear Information System (INIS)

Sorby, W.; Baddeley, H.

1986-01-01

Magnetic resonance imaging is a new, but expensive, modality that is being introduced into clinical use in Australia. While it promises increased safety and accuracy in many situations, its precise role when compared with computed tomography and other modalities is not fully established. Therefore, a Government financed evaluation of costs and efficacy of magnetic resonance imaging units in five teaching hospitals is to be conducted over two years (1986-1988). Experience with the introduction of computed tomography to Australia and other nations has revealed difficulties in the evaluation by conventional methods of a diagnostic technology that is improving rapidly; it is to be hoped that a systematic evaluation of the clinical applications of magnetic resonance imaging will be more achievable and useful

Clinical aspects of dynamic renal imaging with radiochlormerodrin, /sup 99m/Tc pertechnetate, and 131I orthoiodohippurate

International Nuclear Information System (INIS)

Freeman, L.M.

1972-01-01

Three major radionuclide imaging studies are available for assistance in the diagnostic evaluation of renal disorders. Morphology and functional tubular mass may be depicted with mercury-197 chlormerodrin or one of the new technetium-99m renal imaging agents (iron ascorbate or chelate). Excretion data as well as visualization in severely diseased kidneys are obtained with iodine-131 ortho-iodohippurate (hippuran). Vascular patterns of the kidney and lesions within it are obtained using a small volume, high activity bolus of a short-lived radiopharmaceutical, such as technetium-99m pertechnetate. These procedures are to be complementary and not competitive with radiographic studies such as urography, nephrotomography, and selective renal angiography. Each clinical situation must be evaluated individually so that the optimal study or combination of studies is utilized to help supply whatever information is sought. Familiarity with the available imaging techniques and their limitations will help one approach such situations more intelligently. (U.S.)

Study of three-dimensional image display by systemic CT

International Nuclear Information System (INIS)

Fujioka, Tadao; Ebihara, Yoshiyuki; Unei, Hiroshi; Hayashi, Masao; Shinohe, Tooru; Wada, Yuji; Sakai, Takatsugu; Kashima, Kenji; Fujita, Yoshihiro

1989-01-01

A head phantom for CT was scanned at 2 mm intervals from the cervix to the vertex in an attempt to obtain a three-dimensional image display of bones and facial epidermis from an ordinary axial image. Clinically, three-dimensional images were formed at eye sockets and hip joints. With the three-dimensional image using the head phantom, the entire head could be displayed at any angle. Clinically, images were obtained that could not be attained by ordinary CT scanning, such as broken bones in eye sockets and stereoscopic structure at the bottom of a cranium. The three-dimensional image display is considered to be useful in clinical diagnosis. (author)

Quantified Differentiation of Surface Topography for Nano-materials As-Obtained from Atomic Force Microscopy Images

Science.gov (United States)

Gupta, Mousumi; Chatterjee, Somenath

2018-04-01

Surface texture is an important issue to realize the nature (crest and trough) of surfaces. Atomic force microscopy (AFM) image is a key analysis for surface topography. However, in nano-scale, the nature (i.e., deflection or crack) as well as quantification (i.e., height or depth) of deposited layers is essential information for material scientist. In this paper, a gradient-based K-means algorithm is used to differentiate the layered surfaces depending on their color contrast of as-obtained from AFM images. A transformation using wavelet decomposition is initiated to extract the information about deflection or crack on the material surfaces from the same images. Z-axis depth analysis from wavelet coefficients provides information about the crack present in the material. Using the above method corresponding surface information for the material is obtained. In addition, the Gaussian filter is applied to remove the unwanted lines, which occurred during AFM scanning. Few known samples are taken as input, and validity of the above approaches is shown.

Clinical applications of cardiovascular magnetic resonance imaging

International Nuclear Information System (INIS)

Marcu, C.B.; Beek, A.M.; Van Rossum, A.C.

2006-01-01

Cardiovascular magnetic resonance imaging (MRI) has evolved from an effective research tool into a clinically proven, safe and comprehensive imaging modality. It provides anatomic and functional information in acquired and congenital heart disease and is the most precise technique for quantification of ventricular volumes, function and mass. Owing to its excellent interstudy reproducibility, cardiovascular MRI is the optimal method for assessment of changes in ventricular parameters after therapeutic intervention. Delayed contrast enhancement is an accurate and robust method used in the diagnosis of ischemic and nonischemic cardiomyopathies and less common diseases, such as cardiac sarcoidosis and myocarditis. First-pass magnetic contrast myocardial perfusion is becoming an alternative to radionuclide techniques for the detection of coronary atherosclerotic disease. In this review we outline the techniques used in cardiovascular MRI and discuss the most common clinical applications. (author)

Computer-aided diagnosis and artificial intelligence in clinical imaging.

Science.gov (United States)

Shiraishi, Junji; Li, Qiang; Appelbaum, Daniel; Doi, Kunio

2011-11-01

Computer-aided diagnosis (CAD) is rapidly entering the radiology mainstream. It has already become a part of the routine clinical work for the detection of breast cancer with mammograms. The computer output is used as a "second opinion" in assisting radiologists' image interpretations. The computer algorithm generally consists of several steps that may include image processing, image feature analysis, and data classification via the use of tools such as artificial neural networks (ANN). In this article, we will explore these and other current processes that have come to be referred to as "artificial intelligence." One element of CAD, temporal subtraction, has been applied for enhancing interval changes and for suppressing unchanged structures (eg, normal structures) between 2 successive radiologic images. To reduce misregistration artifacts on the temporal subtraction images, a nonlinear image warping technique for matching the previous image to the current one has been developed. Development of the temporal subtraction method originated with chest radiographs, with the method subsequently being applied to chest computed tomography (CT) and nuclear medicine bone scans. The usefulness of the temporal subtraction method for bone scans was demonstrated by an observer study in which reading times and diagnostic accuracy improved significantly. An additional prospective clinical study verified that the temporal subtraction image could be used as a "second opinion" by radiologists with negligible detrimental effects. ANN was first used in 1990 for computerized differential diagnosis of interstitial lung diseases in CAD. Since then, ANN has been widely used in CAD schemes for the detection and diagnosis of various diseases in different imaging modalities, including the differential diagnosis of lung nodules and interstitial lung diseases in chest radiography, CT, and position emission tomography/CT. It is likely that CAD will be integrated into picture archiving and

Evaluation of different physical parameters that affect the clinical image quality for gamma camera by using different radionuclides

International Nuclear Information System (INIS)

Salah, F.A.; Ziada, G.; Hejazy, M.A.; Khalil, W.A.

2008-01-01

Some scintillation camera manufactures adhere to standard code of performance specification established by National Electric Manufactures Association (NEMA). Items such as differential and integral uniformity, spatial resolution energy resolution, etc. are all calculated with reproducible methodology that allows the user reliable technique for creation of these standards to avoid any lack of clinical service that may violate the ethics of patient care. Because 99m Tc is the most frequently used radionuclide in nuclear medicine, many clinics perform the daily uniformity and weekly resolution checks using this radionuclide. But when other commonly used radionuclide such as Tl-201,Ga-67 and I-131 are used, no standardized quality control is performed. So in these study we perform to evaluate the response of ADAC(digital) gamma camera and SELO(analogue) gamma camera to four radionuclide (Tl-201,Ga-67, I-131, and 99m Tc) flood image acquired using different non-uniformity correction tables. In the planer study uniformity and resolution images were obtained using ADAC and SELO cameras, linearity was obtained only by ADAC camera, while in the SPECT study uniformity and contrast images were obtained using ADAC camera only. The response for using different non-uniformity correction tables acquired using different isotopes was different from gamma camera model to another. We can conclude that the most of the gamma camera quality control parameters (uniformity, resolution and contrast) are influenced by variation in the correction tables, while other parameters not affected by this variation like linearity. (author)

Clinical potential for imaging in patients with asthma and other lung disorders.

Science.gov (United States)

DeBoer, Emily M; Spielberg, David R; Brody, Alan S

2017-01-01

The ability of lung imaging to phenotype patients, determine prognosis, and predict response to treatment is expanding in clinical and translational research. The purpose of this perspective is to describe current imaging modalities that might be useful clinical tools in patients with asthma and other lung disorders and to explore some of the new developments in imaging modalities of the lung. These imaging modalities include chest radiography, computed tomography, lung magnetic resonance imaging, electrical impedance tomography, bronchoscopy, and others. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Perfusion magnetic resonance imaging with continuous arterial spin labeling: methods and clinical applications in the central nervous system

Energy Technology Data Exchange (ETDEWEB)

Detre, John A. E-mail: detre@mail.med.upenn.edu; Alsop, David C

1999-05-01

Several methods are now available for measuring cerebral perfusion and related hemodynamic parameters using magnetic resonance imaging (MRI). One class of techniques utilizes electromagnetically labeled arterial blood water as a noninvasive diffusible tracer for blood flow measurements. The electromagnetically labeled tracer has a decay rate of T1, which is sufficiently long to allow perfusion of the tissue and microvasculature to be detected. Alternatively, electromagnetic arterial spin labeling (ASL) may be used to obtain qualitative perfusion contrast for detecting changes in blood flow, similar to the use of susceptibility contrast in blood oxygenation level dependent functional MRI (BOLD fMRI) to detect functional activation in the brain. The ability to obtain blood flow maps using a non-invasive and widely available modality such as MRI should greatly enhance the utility of blood flow measurement as a means of gaining further insight into the broad range of hemodynamically related physiology and pathophysiology. This article describes the biophysical considerations pertaining to the generation of quantitative blood flow maps using a particular form of ASL in which arterial blood water is continuously labeled, termed continuous arterial spin labeling (CASL). Technical advances permit multislice perfusion imaging using CASL with reduced sensitivity to motion and transit time effects. Interpretable cerebral perfusion images can now be reliably obtained in a variety of clinical settings including acute stroke, chronic cerebrovascular disease, degenerative diseases and epilepsy. Over the past several years, the technical and theoretical foundations of CASL perfusion MRI techniques have evolved from feasibility studies into practical usage. Currently existing methodologies are sufficient to make reliable and clinically relevant observations which complement structural assessment using MRI. Future technical improvements should further reduce the acquisition times

[Evaluating the maturity of IT-supported clinical imaging and diagnosis using the Digital Imaging Adoption Model : Are your clinical imaging processes ready for the digital era?

Science.gov (United States)

Studzinski, J

2017-06-01

The Digital Imaging Adoption Model (DIAM) has been jointly developed by HIMSS Analytics and the European Society of Radiology (ESR). It helps evaluate the maturity of IT-supported processes in medical imaging, particularly in radiology. This eight-stage maturity model drives your organisational, strategic and tactical alignment towards imaging-IT planning. The key audience for the model comprises hospitals with imaging centers, as well as external imaging centers that collaborate with hospitals. The assessment focuses on different dimensions relevant to digital imaging, such as software infrastructure and usage, workflow security, clinical documentation and decision support, data exchange and analytical capabilities. With its standardised approach, it enables regional, national and international benchmarking. All DIAM participants receive a structured report that can be used as a basis for presenting, e.g. budget planning and investment decisions at management level.

Clinical feasibility of simultaneous multi-slice imaging with blipped-CAIPI for diffusion-weighted imaging and diffusion-tensor imaging of the brain.

Science.gov (United States)

Yokota, Hajime; Sakai, Koji; Tazoe, Jun; Goto, Mariko; Imai, Hiroshi; Teramukai, Satoshi; Yamada, Kei

2017-12-01

Background Simultaneous multi-slice (SMS) imaging is starting to be used in clinical situation, although evidence of clinical feasibility is scanty. Purpose To prospectively assess the clinical feasibility of SMS diffusion-weighted imaging (DWI) and diffusion-tensor imaging (DTI) with blipped-controlled aliasing in parallel imaging for brain lesions. Material and Methods The institutional review board approved this study. This study included 156 hyperintense lesions on DWI from 32 patients. A slice acceleration factor of 2 was applied for SMS scans, which allowed shortening of the scan time by 41.3%. The signal-to-noise ratio (SNR) was calculated for brain tissue of a selected slice. The contrast-to-noise ratio (CNR), apparent diffusion coefficient (ADC), and fractional anisotropy (FA) were calculated in 36 hyperintense lesions with a diameter of three pixels or more. Visual assessment was performed for all 156 lesions. Tractography of the corticospinal tract of 29 patients was evaluated. The number of tracts and averaged tract length were used for quantitative analysis, and visual assessment was evaluated by grading. Results The SMS scan showed no bias and acceptable 95% limits of agreement compared to conventional scans in SNR, CNR, and ADC on Bland-Altman analyses. Only FA of the lesions was higher in the SMS scan by 9% ( P = 0.016), whereas FA of the surrounding tissues was similar. Quantitative analysis of tractography showed similar values. Visual assessment of DWI hyperintense lesions and tractography also resulted in comparable evaluation. Conclusion SMS imaging was clinically feasible for imaging quality and quantitative values compared with conventional DWI and DTI.

Radiography imaging of cultural heritage obtained with a modified portable X-Ray Fluorescence System

International Nuclear Information System (INIS)

Mendoza Cuevas, Ariadna; Velazquez Maldonado, Luis Ramon

2011-01-01

The sufficiency of imaging quality of the radiographies obtained with a modified portable X-ray fluorescence spectrometer was evaluated for the study of cultural heritage. The proposed instrument use an X-ray tube with Pd anode (2 mm) that allows a maximum voltage and current of 50 kV and 1 mA respectively and a collimation system permit to irradiate a square shape region in the analyzed object by the projection of light beam with the same shape on its surface. The spatial resolution of the obtained radiographic image make possible to localize and well define pentimenti in painting, identify filling materials in a painting under restoration process, the radiogrametry of archaeological bone and the identification of a petrified sphere from an archaeological discovery. The radiographic analysis is proposed for study of physical anthropology in Cuba. (author)

Clinical usefulness of a newly-developed head and neck surface coil for MR imaging

International Nuclear Information System (INIS)

Shimada, Morio; Kogure, Takashi; Hayashi, Sanshin

1995-01-01

To obtain correct diagnosis at early stages of cervical lymph node swelling, especially cases with suspected epipharyngeal carcinoma, and cerebral arterial sclerotic diseases, high-quality MR images visualizing the entire head and neck structures and vessels are of crucial importance. When obtaining images of head and neck regions using a head coil, signal intensity (SI) and signal to noise ratio (SNR) of regions below the hypopharynx are weakened. Moreover, when obtaining images of head and neck regions using an anterior neck coil, SI and SNR of upper regions of epipharynx are also weakened. In an attempt to solve these problems, we developed a new head and neck surface coil for MR imaging. With this new coil we were able to obtain better images (153 cases) from regions below the hypopharynx to the upper regions of the epipharynx in the same time as images obtained using the head coil and anterior neck coil. 2D TOF MR angiographic images (11 cases) obtained by the head and neck surface coil are superior to 2D TOF angiographic images obtained by the anterior neck coil. MR images obtained with this improved method are valuable in the evaluation and management of head and neck region disease. (author)

Evaluation of parathyroid imaging methods with 99mTc-MIBI. The comparison of planar images obtained using a pinhole collimator and a parallel-hole collimator

International Nuclear Information System (INIS)

Fujii, Hirofumi; Iwasaki, Ryuichiro; Hashimoto, Jun; Nakamura, Kayoko; Kunieda, Etsuo; Sanmiya, Toshikazu; Kubo, Atsushi; Ogawa, Koichi; Inagaki, Kazutoshi

1999-01-01

Parathyroid scintigraphy with 99m Tc-MIBI was performed using two kinds of collimators, namely, a pinhole one and a parallel-hole one, to evaluate which one was more suitable for the detection of hyperfunctioning parathyroid lesions. In the studies using 99m Tc source, the pinhole collimator showed better efficiency and spatial resolution in the distance where the parathyroid scan are actually performed. In the phantom study, the nodular activities modeling parathyroid lesions were visualized better on the images obtained using the pinhole collimator. In clinical studies for 30 patients suspicious of hyperparathyroidism, hyperfunctioning parathyroid nodules were better detected when the pinhole collimator was used. In conclusion, the pinhole collimator was thought to be more suitable for parathyroid scintigraphy with 99m Tc-MIBI than the parallel-hole collimator. (author)

Automated detection of delamination and disbond from wavefield images obtained using a scanning laser vibrometer

International Nuclear Information System (INIS)

Sohn, H; Yang, J Y; Dutta, D; DeSimio, M; Olson, S; Swenson, E

2011-01-01

The paper presents signal and image processing algorithms to automatically detect delamination and disbond in composite plates from wavefield images obtained using a scanning laser Doppler vibrometer (LDV). Lamb waves are excited by a lead zirconate titanate transducer (PZT) mounted on the surface of a composite plate, and the out-of-plane velocity field is measured using an LDV. From the scanned time signals, wavefield images are constructed and processed to study the interaction of Lamb waves with hidden delaminations and disbonds. In particular, the frequency–wavenumber (f–k) domain filter and the Laplacian image filter are used to enhance the visibility of defects in the scanned images. Thereafter, a statistical cluster detection algorithm is used to identify the defect location and distinguish damaged specimens from undamaged ones

Automatic classification and detection of clinically relevant images for diabetic retinopathy

Science.gov (United States)

Xu, Xinyu; Li, Baoxin

2008-03-01

We proposed a novel approach to automatic classification of Diabetic Retinopathy (DR) images and retrieval of clinically-relevant DR images from a database. Given a query image, our approach first classifies the image into one of the three categories: microaneurysm (MA), neovascularization (NV) and normal, and then it retrieves DR images that are clinically-relevant to the query image from an archival image database. In the classification stage, the query DR images are classified by the Multi-class Multiple-Instance Learning (McMIL) approach, where images are viewed as bags, each of which contains a number of instances corresponding to non-overlapping blocks, and each block is characterized by low-level features including color, texture, histogram of edge directions, and shape. McMIL first learns a collection of instance prototypes for each class that maximizes the Diverse Density function using Expectation- Maximization algorithm. A nonlinear mapping is then defined using the instance prototypes and maps every bag to a point in a new multi-class bag feature space. Finally a multi-class Support Vector Machine is trained in the multi-class bag feature space. In the retrieval stage, we retrieve images from the archival database who bear the same label with the query image, and who are the top K nearest neighbors of the query image in terms of similarity in the multi-class bag feature space. The classification approach achieves high classification accuracy, and the retrieval of clinically-relevant images not only facilitates utilization of the vast amount of hidden diagnostic knowledge in the database, but also improves the efficiency and accuracy of DR lesion diagnosis and assessment.

Differentiation of true anophthalmia from clinical anophthalmia using neuroradiological imaging

OpenAIRE

Celebi, Ali Riza Cenk; Sasani, Hadi

2014-01-01

Anophthalmia is a condition of the absence of an eye and the presence of a small eye within the orbit. It is associated with many known syndromes. Clinical findings, as well as imaging modalities and genetic analysis, are important in making the diagnosis. Imaging modalities are crucial scanning methods. Cryptophthalmos, cyclopia, synophthalmia and congenital cystic eye should be considered in differential diagnoses. We report two clinical anophthalmic siblings, emphasizing the importance of ...

Retrieving clinically relevant diabetic retinopathy images using a multi-class multiple-instance framework

Science.gov (United States)

Chandakkar, Parag S.; Venkatesan, Ragav; Li, Baoxin

2013-02-01

Diabetic retinopathy (DR) is a vision-threatening complication from diabetes mellitus, a medical condition that is rising globally. Unfortunately, many patients are unaware of this complication because of absence of symptoms. Regular screening of DR is necessary to detect the condition for timely treatment. Content-based image retrieval, using archived and diagnosed fundus (retinal) camera DR images can improve screening efficiency of DR. This content-based image retrieval study focuses on two DR clinical findings, microaneurysm and neovascularization, which are clinical signs of non-proliferative and proliferative diabetic retinopathy. The authors propose a multi-class multiple-instance image retrieval framework which deploys a modified color correlogram and statistics of steerable Gaussian Filter responses, for retrieving clinically relevant images from a database of DR fundus image database.

Clinical value of somatostatin receptor imaging in patients with suspected head and neck paragangliomas

Energy Technology Data Exchange (ETDEWEB)

Schmidt, Matthias; Dietlein, Markus; Weber, Kerstin; Moka, Detlef; Schicha, Harald [Klinik und Poliklinik fuer Nuklearmedizin, Universitaet zu Koeln, Joseph-Stelzmann-Strasse 9, 50924 Koeln (Germany); Fischer, Eva; Michel, Olaf; Stennert, Eberhard [Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenheilkunde, Universitaet zu Koeln, Koeln (Germany)

2002-12-01

Paragangliomas or glomus tumours of the head and neck region are rare somatostatin receptor-expressing neuroendocrine tumours. Precise preoperative diagnosis is of special importance in order to adequately weigh the potential benefit of the operation against the inherent risks of the procedure. In this study, the clinical value of somatostatin receptor imaging was assessed in 19 patients who underwent somatostatin receptor scintigraphy because of known or suspected paraganglioma of the head and neck region. The results were compared with the results of computed tomography and/or magnetic resonance imaging, histology and clinical follow-up. [{sup 111}In-DTPA-D-Phe{sup 1}]-octreotide scintigraphy was performed 4-6 and 24 h after i.v. injection of 140-220 MBq {sup 111}In-octreotide. Whole-body and planar images as well as single-photon emission tomography images were acquired and lesions were graded according to qualitative tracer uptake. Somatostatin receptor imaging was positive in nine patients, identifying paragangliomas for the first time in three patients and recurrent disease in six patients. In one patient, a second, previously unknown paraganglioma site was identified. Negative results were obtained in ten patients. These patients included one suffering from chronic hyperplastic otitis externa, one with granuloma tissue and an organised haematoma, one with an acoustic neuroma, one with an asymmetric internal carotid artery, two with ectasia of the bulbus venae jugularis and one with a jugular vein thrombosis. In two patients with a strong family history of paraganglioma, individual involvement could be excluded. In only one patient did somatostatin receptor imaging and magnetic resonance imaging yield false negative results in respect of recurrent paraganglioma tissue. It is concluded that somatostatin receptor scintigraphy provides important information in patients with suspected paragangliomas of the head and neck region and has a strong impact on further

Model-based PSF and MTF estimation and validation from skeletal clinical CT images.

Science.gov (United States)

Pakdel, Amirreza; Mainprize, James G; Robert, Normand; Fialkov, Jeffery; Whyne, Cari M

2014-01-01

A method was developed to correct for systematic errors in estimating the thickness of thin bones due to image blurring in CT images using bone interfaces to estimate the point-spread-function (PSF). This study validates the accuracy of the PSFs estimated using said method from various clinical CT images featuring cortical bones. Gaussian PSFs, characterized by a different extent in the z (scan) direction than in the x and y directions were obtained using our method from 11 clinical CT scans of a cadaveric craniofacial skeleton. These PSFs were estimated for multiple combinations of scanning parameters and reconstruction methods. The actual PSF for each scan setting was measured using the slanted-slit technique within the image slice plane and the longitudinal axis. The Gaussian PSF and the corresponding modulation transfer function (MTF) are compared against the actual PSF and MTF for validation. The differences (errors) between the actual and estimated full-width half-max (FWHM) of the PSFs were 0.09 ± 0.05 and 0.14 ± 0.11 mm for the xy and z axes, respectively. The overall errors in the predicted frequencies measured at 75%, 50%, 25%, 10%, and 5% MTF levels were 0.06 ± 0.07 and 0.06 ± 0.04 cycles/mm for the xy and z axes, respectively. The accuracy of the estimates was dependent on whether they were reconstructed with a standard kernel (Toshiba's FC68, mean error of 0.06 ± 0.05 mm, MTF mean error 0.02 ± 0.02 cycles/mm) or a high resolution bone kernel (Toshiba's FC81, PSF FWHM error 0.12 ± 0.03 mm, MTF mean error 0.09 ± 0.08 cycles/mm). The method is accurate in 3D for an image reconstructed using a standard reconstruction kernel, which conforms to the Gaussian PSF assumption but less accurate when using a high resolution bone kernel. The method is a practical and self-contained means of estimating the PSF in clinical CT images featuring cortical bones, without the need phantoms or any prior knowledge about the scanner-specific parameters.

Model-based PSF and MTF estimation and validation from skeletal clinical CT images

International Nuclear Information System (INIS)

Pakdel, Amirreza; Mainprize, James G.; Robert, Normand; Fialkov, Jeffery; Whyne, Cari M.

2014-01-01

Purpose: A method was developed to correct for systematic errors in estimating the thickness of thin bones due to image blurring in CT images using bone interfaces to estimate the point-spread-function (PSF). This study validates the accuracy of the PSFs estimated using said method from various clinical CT images featuring cortical bones. Methods: Gaussian PSFs, characterized by a different extent in the z (scan) direction than in the x and y directions were obtained using our method from 11 clinical CT scans of a cadaveric craniofacial skeleton. These PSFs were estimated for multiple combinations of scanning parameters and reconstruction methods. The actual PSF for each scan setting was measured using the slanted-slit technique within the image slice plane and the longitudinal axis. The Gaussian PSF and the corresponding modulation transfer function (MTF) are compared against the actual PSF and MTF for validation. Results: The differences (errors) between the actual and estimated full-width half-max (FWHM) of the PSFs were 0.09 ± 0.05 and 0.14 ± 0.11 mm for the xy and z axes, respectively. The overall errors in the predicted frequencies measured at 75%, 50%, 25%, 10%, and 5% MTF levels were 0.06 ± 0.07 and 0.06 ± 0.04 cycles/mm for the xy and z axes, respectively. The accuracy of the estimates was dependent on whether they were reconstructed with a standard kernel (Toshiba's FC68, mean error of 0.06 ± 0.05 mm, MTF mean error 0.02 ± 0.02 cycles/mm) or a high resolution bone kernel (Toshiba's FC81, PSF FWHM error 0.12 ± 0.03 mm, MTF mean error 0.09 ± 0.08 cycles/mm). Conclusions: The method is accurate in 3D for an image reconstructed using a standard reconstruction kernel, which conforms to the Gaussian PSF assumption but less accurate when using a high resolution bone kernel. The method is a practical and self-contained means of estimating the PSF in clinical CT images featuring cortical bones, without the need phantoms or any prior knowledge about the

Model-based PSF and MTF estimation and validation from skeletal clinical CT images

Energy Technology Data Exchange (ETDEWEB)

Pakdel, Amirreza [Sunnybrook Research Institute, Toronto, Ontario M4N 3M5, Canada and Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario M5S 3M2 (Canada); Mainprize, James G.; Robert, Normand [Sunnybrook Research Institute, Toronto, Ontario M4N 3M5 (Canada); Fialkov, Jeffery [Division of Plastic Surgery, Sunnybrook Health Sciences Center, Toronto, Ontario M4N 3M5, Canada and Department of Surgery, University of Toronto, Toronto, Ontario M5S 3M2 (Canada); Whyne, Cari M., E-mail: cari.whyne@sunnybrook.ca [Sunnybrook Research Institute, Toronto, Ontario M4N 3M5, Canada and Department of Surgery, Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario M5S 3M2 (Canada)

2014-01-15

Purpose: A method was developed to correct for systematic errors in estimating the thickness of thin bones due to image blurring in CT images using bone interfaces to estimate the point-spread-function (PSF). This study validates the accuracy of the PSFs estimated using said method from various clinical CT images featuring cortical bones. Methods: Gaussian PSFs, characterized by a different extent in the z (scan) direction than in the x and y directions were obtained using our method from 11 clinical CT scans of a cadaveric craniofacial skeleton. These PSFs were estimated for multiple combinations of scanning parameters and reconstruction methods. The actual PSF for each scan setting was measured using the slanted-slit technique within the image slice plane and the longitudinal axis. The Gaussian PSF and the corresponding modulation transfer function (MTF) are compared against the actual PSF and MTF for validation. Results: The differences (errors) between the actual and estimated full-width half-max (FWHM) of the PSFs were 0.09 ± 0.05 and 0.14 ± 0.11 mm for the xy and z axes, respectively. The overall errors in the predicted frequencies measured at 75%, 50%, 25%, 10%, and 5% MTF levels were 0.06 ± 0.07 and 0.06 ± 0.04 cycles/mm for the xy and z axes, respectively. The accuracy of the estimates was dependent on whether they were reconstructed with a standard kernel (Toshiba's FC68, mean error of 0.06 ± 0.05 mm, MTF mean error 0.02 ± 0.02 cycles/mm) or a high resolution bone kernel (Toshiba's FC81, PSF FWHM error 0.12 ± 0.03 mm, MTF mean error 0.09 ± 0.08 cycles/mm). Conclusions: The method is accurate in 3D for an image reconstructed using a standard reconstruction kernel, which conforms to the Gaussian PSF assumption but less accurate when using a high resolution bone kernel. The method is a practical and self-contained means of estimating the PSF in clinical CT images featuring cortical bones, without the need phantoms or any prior knowledge

Patient-specific scatter correction in clinical cone beam computed tomography imaging made possible by the combination of Monte Carlo simulations and a ray tracing algorithm

International Nuclear Information System (INIS)

Thing, Rune S.; Bernchou, Uffe; Brink, Carsten; Mainegra-Hing, Ernesto

2013-01-01

Purpose: Cone beam computed tomography (CBCT) image quality is limited by scattered photons. Monte Carlo (MC) simulations provide the ability of predicting the patient-specific scatter contamination in clinical CBCT imaging. Lengthy simulations prevent MC-based scatter correction from being fully implemented in a clinical setting. This study investigates the combination of using fast MC simulations to predict scatter distributions with a ray tracing algorithm to allow calibration between simulated and clinical CBCT images. Material and methods: An EGSnrc-based user code (egs c bct), was used to perform MC simulations of an Elekta XVI CBCT imaging system. A 60keV x-ray source was used, and air kerma scored at the detector plane. Several variance reduction techniques (VRTs) were used to increase the scatter calculation efficiency. Three patient phantoms based on CT scans were simulated, namely a brain, a thorax and a pelvis scan. A ray tracing algorithm was used to calculate the detector signal due to primary photons. A total of 288 projections were simulated, one for each thread on the computer cluster used for the investigation. Results: Scatter distributions for the brain, thorax and pelvis scan were simulated within 2 % statistical uncertainty in two hours per scan. Within the same time, the ray tracing algorithm provided the primary signal for each of the projections. Thus, all the data needed for MC-based scatter correction in clinical CBCT imaging was obtained within two hours per patient, using a full simulation of the clinical CBCT geometry. Conclusions: This study shows that use of MC-based scatter corrections in CBCT imaging has a great potential to improve CBCT image quality. By use of powerful VRTs to predict scatter distributions and a ray tracing algorithm to calculate the primary signal, it is possible to obtain the necessary data for patient specific MC scatter correction within two hours per patient

Image Montaging for Creating a Virtual Pathology Slide: An Innovative and Economical Tool to Obtain a Whole Slide Image.

Science.gov (United States)

Banavar, Spoorthi Ravi; Chippagiri, Prashanthi; Pandurangappa, Rohit; Annavajjula, Saileela; Rajashekaraiah, Premalatha Bidadi

2016-01-01

Background . Microscopes are omnipresent throughout the field of biological research. With microscopes one can see in detail what is going on at the cellular level in tissues. Though it is a ubiquitous tool, the limitation is that with high magnification there is a small field of view. It is often advantageous to see an entire sample at high magnification. Over the years technological advancements in optics have helped to provide solutions to this limitation of microscopes by creating the so-called dedicated "slide scanners" which can provide a "whole slide digital image." These scanners can provide seamless, large-field-of-view, high resolution image of entire tissue section. The only disadvantage of such complete slide imaging system is its outrageous cost, thereby hindering their practical use by most laboratories, especially in developing and low resource countries. Methods . In a quest for their substitute, we tried commonly used image editing software Adobe Photoshop along with a basic image capturing device attached to a trinocular microscope to create a digital pathology slide. Results . The seamless image created using Adobe Photoshop maintained its diagnostic quality. Conclusion . With time and effort photomicrographs obtained from a basic camera-microscope set up can be combined and merged in Adobe Photoshop to create a whole slide digital image of practically usable quality at a negligible cost.

Cancer imaging phenomics toolkit: quantitative imaging analytics for precision diagnostics and predictive modeling of clinical outcome.

Science.gov (United States)

Davatzikos, Christos; Rathore, Saima; Bakas, Spyridon; Pati, Sarthak; Bergman, Mark; Kalarot, Ratheesh; Sridharan, Patmaa; Gastounioti, Aimilia; Jahani, Nariman; Cohen, Eric; Akbari, Hamed; Tunc, Birkan; Doshi, Jimit; Parker, Drew; Hsieh, Michael; Sotiras, Aristeidis; Li, Hongming; Ou, Yangming; Doot, Robert K; Bilello, Michel; Fan, Yong; Shinohara, Russell T; Yushkevich, Paul; Verma, Ragini; Kontos, Despina

2018-01-01

The growth of multiparametric imaging protocols has paved the way for quantitative imaging phenotypes that predict treatment response and clinical outcome, reflect underlying cancer molecular characteristics and spatiotemporal heterogeneity, and can guide personalized treatment planning. This growth has underlined the need for efficient quantitative analytics to derive high-dimensional imaging signatures of diagnostic and predictive value in this emerging era of integrated precision diagnostics. This paper presents cancer imaging phenomics toolkit (CaPTk), a new and dynamically growing software platform for analysis of radiographic images of cancer, currently focusing on brain, breast, and lung cancer. CaPTk leverages the value of quantitative imaging analytics along with machine learning to derive phenotypic imaging signatures, based on two-level functionality. First, image analysis algorithms are used to extract comprehensive panels of diverse and complementary features, such as multiparametric intensity histogram distributions, texture, shape, kinetics, connectomics, and spatial patterns. At the second level, these quantitative imaging signatures are fed into multivariate machine learning models to produce diagnostic, prognostic, and predictive biomarkers. Results from clinical studies in three areas are shown: (i) computational neuro-oncology of brain gliomas for precision diagnostics, prediction of outcome, and treatment planning; (ii) prediction of treatment response for breast and lung cancer, and (iii) risk assessment for breast cancer.

Radiopharmaceuticals: nanoparticles like multi-functional systems for the obtaining in vivo of molecular images

International Nuclear Information System (INIS)

Ferro F, G.; Ramirez de la Cruz, F. M.; Ocampo G, B. E.; Morales A, E.; Santos C, C. L.; Mendoza S, A. N.

2010-01-01

The techniques of obtaining direct or indirect molecular images detect and register the space-temporary distribution of molecular or cellular processes for biochemical, biological, diagnostic and therapeutic applications. The advanced techniques of image like the nuclear magnetic resonance, the single photon emission computed tomography, the positron emission tomography and the images of optic fluorescence have been used successfully to detect these processes. On the other hand, the utility of the nanoparticles for any application is dependent of the physicochemical properties that present, being possible to modify their surface when making them react with different biomolecules what allows the formation of conjugates with specific molecular recognition. The joint of various protein molecules, peptides or oligonucleotides to the surface of a nanoparticle produce a multi-functional system able to increase the multivalent joints from the nanoparticles-biomolecules to their receivers for the obtaining of molecular images in vivo. The peptides stimulate, regulate or inhibit numerous functions of the life, acting mainly as information transmitters and activity coordinators of several tissues in the organism. The receivers of regulator peptides are over represented in numerous types of cancer cells and they are protein structures. These receivers have been used as white molecular of marked peptides, to locate primary malignant tumors and their metastasis, using the diagnostic techniques of molecular image mentioned above, which consist basically on the radio peptides use and conjugated peptides to fluoro chromes, to metallic nanoparticles and nano crystals. A summary of the work is presented carried out by the personnel of the Radio-active Materials and Chemistry Departments of the Instituto Nacional de Investigaciones Nucleares in this field. (Author)

Correlation between measured energy expenditure and clinically obtained variables in trauma and sepsis patients.

Science.gov (United States)

Frankenfield, D C; Omert, L A; Badellino, M M; Wiles, C E; Bagley, S M; Goodarzi, S; Siegel, J H

1994-01-01

Indirect calorimetry is the preferred method for determining caloric requirements of patients, but availability of the device is limited by high cost. A study was therefore conducted to determine whether clinically obtainable variables could be used to predict metabolic rate. Patients with severe trauma or sepsis who required mechanical ventilation were measured by an open-circuit indirect calorimeter. Several clinical variables were obtained simultaneously. Measurements were repeated every 12 hours for up to 10 days. Twenty-six trauma and 30 sepsis patients were measured 423 times. Mean resting energy expenditure was 36 +/- 7 kcal/kg (trauma) vs 45 +/- 8 kcal/kg (sepsis) (p types.

An adaptive optics imaging system designed for clinical use

Science.gov (United States)

Zhang, Jie; Yang, Qiang; Saito, Kenichi; Nozato, Koji; Williams, David R.; Rossi, Ethan A.

2015-01-01

Here we demonstrate a new imaging system that addresses several major problems limiting the clinical utility of conventional adaptive optics scanning light ophthalmoscopy (AOSLO), including its small field of view (FOV), reliance on patient fixation for targeting imaging, and substantial post-processing time. We previously showed an efficient image based eye tracking method for real-time optical stabilization and image registration in AOSLO. However, in patients with poor fixation, eye motion causes the FOV to drift substantially, causing this approach to fail. We solve that problem here by tracking eye motion at multiple spatial scales simultaneously by optically and electronically integrating a wide FOV SLO (WFSLO) with an AOSLO. This multi-scale approach, implemented with fast tip/tilt mirrors, has a large stabilization range of ± 5.6°. Our method consists of three stages implemented in parallel: 1) coarse optical stabilization driven by a WFSLO image, 2) fine optical stabilization driven by an AOSLO image, and 3) sub-pixel digital registration of the AOSLO image. We evaluated system performance in normal eyes and diseased eyes with poor fixation. Residual image motion with incremental compensation after each stage was: 1) ~2–3 arc minutes, (arcmin) 2) ~0.5–0.8 arcmin and, 3) ~0.05–0.07 arcmin, for normal eyes. Performance in eyes with poor fixation was: 1) ~3–5 arcmin, 2) ~0.7–1.1 arcmin and 3) ~0.07–0.14 arcmin. We demonstrate that this system is capable of reducing image motion by a factor of ~400, on average. This new optical design provides additional benefits for clinical imaging, including a steering subsystem for AOSLO that can be guided by the WFSLO to target specific regions of interest such as retinal pathology and real-time averaging of registered images to eliminate image post-processing. PMID:26114033

Utility of positron emission tomography-magnetic resonance imaging in musculoskeletal imaging

Institute of Scientific and Technical Information of China (English)

Ammar A Chaudhry; Maryam Gul; Elaine Gould; Mathew Teng; Kevin Baker; Robert Matthews

2016-01-01

Differentiation between neoplastic and nonneoplastic conditions magnetic resonance imaging(MRI) has established itself as one of the key clinical tools in evaluation of musculoskeletal pathology. However, MRI still has several key limitations which require supplemental information from additional modalities to complete evaluation of various disorders. This has led to the development hybrid positron emission tomography(PET)-MRI which is rapidly evolving to address key clinical questions by using the morphological strengths of MRI and functional information of PET imaging. In this article, we aim to review physical principles and techniques of PET-MRI and discuss clinical utility of functional information obtained from PET imaging and structural information obtained from MRI imaging for the evaluation of musculoskeletal pathology. More specifically, this review highlights the role of PET-MRI in musculoskeletal oncology including initial diagnosis and staging, treatment planning and posttreatment follow-up. Also we will review utility of PET-MRI in evaluating musculoskeletal infections(especially in the immunocompromised and diabetics) and inflammatory condition. Additionally, common pitfalls of PET-MRI will be addressed.

Epithelioid sarcoma: clinical, MR imaging and pathologic findings

International Nuclear Information System (INIS)

Hanna, S.L.; Kaste, S.; Jenkins, J.J.; Hewan-Lowe, K.; Spence, J.V.; Gupta, M.; Monson, D.; Fletcher, B.D.

2002-01-01

Objective. To report and describe the MR imaging features of eight new cases of this rare soft tissue sarcoma and correlate them with the clinical and histologic findings.Design and patients. Retrospective analysis was carried out for the MR imaging characteristics and histologic findings of eight patients with pathologically proven epithelioid sarcoma and the literature was reviewed. Findings were correlated in each case with the patient's clinical presentation and eventual outcome.Results. The patients, whose primary tumors ranged from 2.5 cm to 19 cm in maximum dimension, were 1 to 90 years of age. Tumors involved the extremities (n=5), the scalp (n=2) and the paraspinal muscles (n=1). Five tumors presented as well-defined, frequently painful, deeply situated masses and three as subcutaneous nodules or cutaneous ulcers with no palpable mass. Four patients had associated regional lymphadenopathy and one had distant metastases at diagnosis. MR imaging showed tumor infiltration of adjacent tissues in seven patients. Signal characteristics reflected varying degrees of cellularity, and the presence of necrosis, hemorrhage, fibrosis, hyalinization and inflammation. Bone marrow involvement was demonstrated in one patient. Clinical outcomes were generally poor.Conclusions. Epithelioid sarcoma is an aggressive soft tissue sarcoma with a varied clinical presentation, growth pattern, MR signal characteristics and histologic picture. The tumor favors the distal extremities and is commonly infiltrative and accompanied by enlarged regional lymph nodes. This neoplasm may present as an intramuscular mass but should also be suspected in patients with ulcerating cutaneous nodules with or without regional lymphadenopathy. (orig.)

Intraobserver and interobserver reproducibility in linear measurements on axial images obtained by cone-beam computed tomography

Energy Technology Data Exchange (ETDEWEB)

De Silva, Nathalia Cristine; Junqueira, Jose Luiz Cinta; Panzarella, Francine Keuhi; Raitz, Ricardo [Sao Leopoldo Mandic Research Center, Dept. of Oral Radiology, College of Dentistry, Sao Paulo (Brazil); Brriviera, Mauricio [Dept. of Oral Radiology, College of Dentistry, Catholic University of Brasilia, Sao Paulo (Brazil)

2017-03-15

This study was performed to investigate the intra- and inter-observer variability in linear measurements with axial images obtained by PreXion (PreXion Inc., San Mateo, USA) and i-CAT (Imaging Sciences International, Xoran Technologies Inc., Hatfield, USA) CBCT scanners, with different voxel sizes. A cylindrical object made from nylon with radiopaque markers (phantom) was scanned by i-CAT and PreXion 3D devices. For each axial image, measurements were taken twice in the horizontal (distance A-B) and vertical (distance C-D) directions, randomly, with a one-week interval between measurements, by four oral radiologists with five years or more experience in the use of these measuring tools. All of the obtained linear measurements had lower values than those of the phantom. The statistical analysis showed high intra- and inter-observer reliability (p=0.297). Compared to the real measurements, the measurements obtained using the i-CAT device and PreXion tomography, on average, revealed absolute errors ranging from 0.22 to 0.59 mm and from 0.23 to 0.63 mm, respectively. It can be concluded that both scanners are accurate, although the linear measurements are underestimations, with no significant differences between the evaluators.

Clinical and imaging manifestations of adult mitochondrial encephalomyopathy

International Nuclear Information System (INIS)

Xing Haifang; Dai Jianping; Gao Peiyi; Li Shaowu; Ren Haitao; Zhu Mingwang; Wang Qinghe

2005-01-01

Objective: To investigate clinical manifestations and neuroimaging in the adult patients with mitochondrial encephalomyopathy (ME). Methods: Systematic study was performed on the clinical features of six adult patients with ME with observations on electromyogram (EMG), electroencephalogram (EEG), the blood lactic acid level, muscle biopsies results and neuroimaging features of CT and MRI. Results: The main clinical features were characterized by seizures, intolerance to exercise, audio-visual dysfunction, mental retardation, and so forth. EMG showed neurogenic damages (4/5 cases); EEG showed extensive mild to severe abnormal activities (3/3 cases) and lactic acidosis was also observed (4 /4 cases). Neuroimaging findings included symmetric supratentorial multi foci lesions, located in frontal, temporal, parietal, and occipital lobes, thalami and basal ganglia with widening of ventricles and cerebral atrophy; the neuroimaging findings also included hyperintensity on T 2 -weighted images and hypointensity/ isointensity on T 1 -weighted images; No stenosis and occlusion of main artery was displayed by magnetic resonance angiography (MRA). Muscle biopsies showed red ragged fiber (RRF) (4/6 cases). Conclusions: Based on clinical features and neuroimaging, diagnosis of ME in early stage may be made in combination with muscle biopsy. (authors)

Magnetic Resonance Imaging in Malawi: Contributions to Clinical ...

African Journals Online (AJOL)

Magnetic Resonance Imaging in Malawi: Contributions to Clinical Care, Medical Education and Biomedical Research. MJ Potchen, S Kampondeni, GL Birbeck, CA Hammond, A Gonani, KS Phiri, KB Seydel, TE Taylor ...

Optical Imaging of Ionizing Radiation from Clinical Sources.

Science.gov (United States)

Shaffer, Travis M; Drain, Charles Michael; Grimm, Jan

2016-11-01

Nuclear medicine uses ionizing radiation for both in vivo diagnosis and therapy. Ionizing radiation comes from a variety of sources, including x-rays, beam therapy, brachytherapy, and various injected radionuclides. Although PET and SPECT remain clinical mainstays, optical readouts of ionizing radiation offer numerous benefits and complement these standard techniques. Furthermore, for ionizing radiation sources that cannot be imaged using these standard techniques, optical imaging offers a unique imaging alternative. This article reviews optical imaging of both radionuclide- and beam-based ionizing radiation from high-energy photons and charged particles through mechanisms including radioluminescence, Cerenkov luminescence, and scintillation. Therapeutically, these visible photons have been combined with photodynamic therapeutic agents preclinically for increasing therapeutic response at depths difficult to reach with external light sources. Last, new microscopy methods that allow single-cell optical imaging of radionuclides are reviewed. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

A Picture is Worth 1,000 Words. The Use of Clinical Images in Electronic Medical Records.

Science.gov (United States)

Ai, Angela C; Maloney, Francine L; Hickman, Thu-Trang; Wilcox, Allison R; Ramelson, Harley; Wright, Adam

2017-07-12

To understand how clinicians utilize image uploading tools in a home grown electronic health records (EHR) system. A content analysis of patient notes containing non-radiological images from the EHR was conducted. Images from 4,000 random notes from July 1, 2009 - June 30, 2010 were reviewed and manually coded. Codes were assigned to four properties of the image: (1) image type, (2) role of image uploader (e.g. MD, NP, PA, RN), (3) practice type (e.g. internal medicine, dermatology, ophthalmology), and (4) image subject. 3,815 images from image-containing notes stored in the EHR were reviewed and manually coded. Of those images, 32.8% were clinical and 66.2% were non-clinical. The most common types of the clinical images were photographs (38.0%), diagrams (19.1%), and scanned documents (14.4%). MDs uploaded 67.9% of clinical images, followed by RNs with 10.2%, and genetic counselors with 6.8%. Dermatology (34.9%), ophthalmology (16.1%), and general surgery (10.8%) uploaded the most clinical images. The content of clinical images referencing body parts varied, with 49.8% of those images focusing on the head and neck region, 15.3% focusing on the thorax, and 13.8% focusing on the lower extremities. The diversity of image types, content, and uploaders within a home grown EHR system reflected the versatility and importance of the image uploading tool. Understanding how users utilize image uploading tools in a clinical setting highlights important considerations for designing better EHR tools and the importance of interoperability between EHR systems and other health technology.

Clinical diagnosis and brain imaging in nuclear medicine

International Nuclear Information System (INIS)

Fujie, Hiroshi

1989-01-01

Fifty-five patients of cerebral occlusive diseases were studied using IMP and single photon emission tomograph (HEADTOME-II). Early imaging was begun after intravenous injection of IMP and delayed imaging was performed 3 hours more later. We classified the change of IMP distribution into 4 types, type 1: no uptake of the lesion in both early and delayed images, type 2: low IMP uptake of the lesion in early images but recognized redistribution of IMP is delayed images, type 3: high IMP uptake of the lesion in both early and delayed images, type 4: high IMP uptake of the lesion in early images but it decreased more rapidly in delayed images. In cases of type 3 and 4 recanalization of the occlusive arteries was found by cerebral angiography. The difference of IMP distribution has relation to the time of recanalization and the amount of collateral circulation at the lesion. Clinical prognosis shows a tendency to be better in cases of type 2 and 4 than type 1 and 3. IMP brain scans with SPECT seems useful for estimating the prognosis of patients. (author)

Clinical utility of partial flip angle T2-weighted spin-echo imaging of the brain

International Nuclear Information System (INIS)

Chang, K.H.; Yi, J.G.; Han, M.H.; Han, M.C.; Kim, C.W.; Cho, M.H.; Cho, Z.H.

1990-01-01

To assess the clinical usefulness of partial flip angle (PFA) spin-echo (SE) brain imaging, a total of eighty patients were examined with both conventional double echo T2-weighted SE (2500/30, 80/90deg/one excitation) and PFA double echo SE (1200/30, 70/45deg/two excitations) on 2.0T system. Two comparative studies were performed: (1) In 65 patients PFA SE technique was compared with conventional SE without flow compensating gradients, and (2) in 15 patients the former was compared with the latter with flow compensating gradients. Imaging time was nearly identical in each sequence. In both studies we found that PFA T2-weighted SE images were almost identical to those obtained with the conventional SE technique in the contrast characteristics and the detection rate of the abnormalities (100%, 85/85 lesions), and more importantly, PFA SE revealed few flow artifacts in the brain stem, temporal lobes and basal ganglia which were frequently seen on conventional SE without flow compensating gradients. Additionally, PFA SE images demonstrated no suppression of CSF flow void in the aqueduct which was commonly seen on conventional SE with flow compensating gradients. In overall image quality, the PFA SE images, particularly the second echo images, were almost comparable with those of conventional SE with flow compensating gradients. A flip angle of 45deg seems to be close to Ernst angle, the angle at which maximum signal occurs, for a given TR of 1200 msec for CSF and most of the abnormalities containing higher water content. In conclusion, PFA SE sequence (i.e. 1200/30, 70/45deg/2) appears to be useful as a primary or an adjunctive technique in certain clinical circumstances, particularly in imaging of hydrocephalic patients for assessing aqueductal patency. (orig.)

Clinical use and evaluation of coded excitation in B-mode images

DEFF Research Database (Denmark)

Misaridis, Athanasios; Pedersen, M. H.; Jensen, Jørgen Arendt

2000-01-01

on a predistorted FM excitation and a mismatched compression filter designed for medical ultrasonic applications. The attenuation effect, analyzed in this paper using the ambiguity function and simulations, dictated the choice of the coded waveform. In this study clinical images, images of wire phantoms......Use of long encoded waveforms can be advantageous in ultrasound imaging, as long as the pulse compression mechanism ensures low range sidelobes and preserves both axial resolution and contrast. A coded excitation/compression scheme was previously presented by our group, which is based...... was programmed to allow alternating excitation on every second frame. That offers the possibility of direct comparison of the same set of image pairs; one with pulsed and one with encoded excitation. Abdominal clinical images from healthy volunteers were acquired and statistically analyzed by means of the auto...

Parotid lymphomas - clinical and computed tomogrphic imaging ...

African Journals Online (AJOL)

Objective. To review the clinical presentation and computed tomography (CT) imaging characteristics of all parotid lymphomas diagnosed at the study institution over a 7-year period. Design. Retrospective chart review of parotid lymphomas diagnosed between 1997 and 2004. Subjects. A total of 121 patients with parotid ...

Obtaining Approximate Values of Exterior Orientation Elements of Multi-Intersection Images Using Particle Swarm Optimization

Science.gov (United States)

Li, X.; Li, S. W.

2012-07-01

In this paper, an efficient global optimization algorithm in the field of artificial intelligence, named Particle Swarm Optimization (PSO), is introduced into close range photogrammetric data processing. PSO can be applied to obtain the approximate values of exterior orientation elements under the condition that multi-intersection photography and a small portable plane control frame are used. PSO, put forward by an American social psychologist J. Kennedy and an electrical engineer R.C. Eberhart, is a stochastic global optimization method based on swarm intelligence, which was inspired by social behavior of bird flocking or fish schooling. The strategy of obtaining the approximate values of exterior orientation elements using PSO is as follows: in terms of image coordinate observed values and space coordinates of few control points, the equations of calculating the image coordinate residual errors can be given. The sum of absolute value of each image coordinate is minimized to be the objective function. The difference between image coordinate observed value and the image coordinate computed through collinear condition equation is defined as the image coordinate residual error. Firstly a gross area of exterior orientation elements is given, and then the adjustment of other parameters is made to get the particles fly in the gross area. After iterative computation for certain times, the satisfied approximate values of exterior orientation elements are obtained. By doing so, the procedures like positioning and measuring space control points in close range photogrammetry can be avoided. Obviously, this method can improve the surveying efficiency greatly and at the same time can decrease the surveying cost. And during such a process, only one small portable control frame with a couple of control points is employed, and there are no strict requirements for the space distribution of control points. In order to verify the effectiveness of this algorithm, two experiments are

OBTAINING APPROXIMATE VALUES OF EXTERIOR ORIENTATION ELEMENTS OF MULTI-INTERSECTION IMAGES USING PARTICLE SWARM OPTIMIZATION

Directory of Open Access Journals (Sweden)

X. Li

2012-07-01

Full Text Available In this paper, an efficient global optimization algorithm in the field of artificial intelligence, named Particle Swarm Optimization (PSO, is introduced into close range photogrammetric data processing. PSO can be applied to obtain the approximate values of exterior orientation elements under the condition that multi-intersection photography and a small portable plane control frame are used. PSO, put forward by an American social psychologist J. Kennedy and an electrical engineer R.C. Eberhart, is a stochastic global optimization method based on swarm intelligence, which was inspired by social behavior of bird flocking or fish schooling. The strategy of obtaining the approximate values of exterior orientation elements using PSO is as follows: in terms of image coordinate observed values and space coordinates of few control points, the equations of calculating the image coordinate residual errors can be given. The sum of absolute value of each image coordinate is minimized to be the objective function. The difference between image coordinate observed value and the image coordinate computed through collinear condition equation is defined as the image coordinate residual error. Firstly a gross area of exterior orientation elements is given, and then the adjustment of other parameters is made to get the particles fly in the gross area. After iterative computation for certain times, the satisfied approximate values of exterior orientation elements are obtained. By doing so, the procedures like positioning and measuring space control points in close range photogrammetry can be avoided. Obviously, this method can improve the surveying efficiency greatly and at the same time can decrease the surveying cost. And during such a process, only one small portable control frame with a couple of control points is employed, and there are no strict requirements for the space distribution of control points. In order to verify the effectiveness of this algorithm

Three-dimensional cardiac cine imaging using the kat ARC acceleration: Initial experience in clinical adult patients at 3T.

Science.gov (United States)

Okuda, Shigeo; Yamada, Yoshitake; Tanimoto, Akihiro; Fujita, Jun; Sano, Motoaki; Fukuda, Keiichi; Kuribayashi, Sachio; Jinzaki, Masahiro; Nozaki, Atsushi; Lai, Peng

2015-09-01

Three-dimensional cardiac cine imaging has demonstrated promising clinical 1.5-Tesla results; however, its application to 3T scanners has been limited because of the higher sensitivity to off-resonance artifacts. The aim of this study was to apply 3D cardiac cine imaging during a single breath hold in clinical patients on a 3T scanner using the kat ARC (k- and adaptive-t auto-calibrating reconstruction for Cartesian sampling) technique and to evaluate the interchangeability between 2D and 3D cine imaging for cardiac functional analysis and detection of abnormalities in regional wall motion. Following institutional review board approval, we obtained 2D cine images with an acceleration factor of two during multiple breath holds and 3D cine images with a net scan acceleration factor of 7.7 during a single breath hold in 20 patients using a 3T unit. Two readers independently evaluated the wall motion of the left ventricle (LV) using a 5-point scale, and the consistency in the detection of regional wall motion abnormality between 2D and 3D cine was analyzed by Cohen's kappa test. The LV volume was calculated at end-diastole and end-systole (LVEDV, LVESV); the ejection fraction (LVEF) and myocardial weight (LVmass) were also calculated. The relationship between functional parameters calculated for 2D and 3D cine images was analyzed using Pearson's correlation analysis. The bias and 95% limit of agreement (LA) were calculated using Bland-Altman plots. In addition, a qualitative evaluation of image quality was performed with regard to the myocardium-blood contrast, noise level and boundary definition. Despite slight degradation in image quality for 3D cine, excellent agreement was obtained for the detection of wall motion abnormalities between 2D and 3D cine images (κ=0.84 and 0.94 for each reader). Excellent correlations between the two imaging methods were shown for the evaluation of functional parameters (r>0.97). Slight differences in LVEDV, LVESV, LVEF and LVmass

A new clinical tool for the quantification of myocardial CT perfusion imaging in patients with suspected Ischemic Heart Disease

Energy Technology Data Exchange (ETDEWEB)

Ruiz Muñoz, A.; Dux-Santoy Hurtado, L.; Rodriguez Palomares, J.L.; Piella Fenoy, G.

2016-07-01

In the clinical practice, the evaluation of myocardial perfusion by using Computed Tomography (CT) Imaging is usually performed visually or semi-quantitatively. The scarcity of quantitative perfusion data not always allows a proper diagnose of patients which are suspected of suffering from some diseases, such as Ischemic Heart Disease (IHD). In this work, a clinical tool for the automatic quantification of myocardial perfusion in patients with suspected IHD is proposed. Myocardial perfusion is assessed based on a combined diagnosis protocol (CT/CTP protocol) which involves the acquisition of two contrastenhanced CT images, one obtained at rest and another acquired under pharmacological stress. The clinical tool allows the automatic quantification of perfusion in different myocardial segments defined according to the 16-AHA-segmentation model of the left ventricle, by providing the mean of Hounsfield Units in those regions. Based on this analysis, the clinicians can compare the values at baseline and at hyperemia, and they can better determine hypoperfusion defects in patients with IHD. The validation of the clinical tool was performed by comparing automatic and manual perfusion measurements of 10 patients with suspected IHD who were previously assessed with Single Photon Emission Computed Tomography (SPECT) for perfusion analysis. A strong linear correlation was found between the automatic and manual results. Afterwards, perfusion defects obtained from CT/CTP protocol were compared to perfusion defects from SPECT, to assess the applicability of this clinical tool for the diagnosis of IHD. (Author)

Clinical implementation of x-ray phase-contrast imaging: Theoretical foundations and design considerations

International Nuclear Information System (INIS)

Wu Xizeng; Liu Hong

2003-01-01

Theoretical foundation and design considerations of a clinical feasible x-ray phase contrast imaging technique were presented in this paper. Different from the analysis of imaging phase object with weak absorption in literature, we proposed a new formalism for in-line phase-contrast imaging to analyze the effects of four clinically important factors on the phase contrast. These are the body parts attenuation, the spatial coherence of spherical waves from a finite-size focal spot, and polychromatic x-ray and radiation doses to patients for clinical applications. The theory presented in this paper can be applied widely in diagnostic x-ray imaging procedures. As an example, computer simulations were conducted and optimal design parameters were derived for clinical mammography. The results of phantom experiments were also presented which validated the theoretical analysis and computer simulations

MR imaging and clinical findings of spontaneous spinal epidural hematoma

Energy Technology Data Exchange (ETDEWEB)

Kim, Sam Soo [Seoul City Boramae Hospital, Seoul (Korea, Republic of); Han, Moon Hee; Kim, Hyun Beom [College of Medicine, Seoul National University, Seoul (Korea, Republic of)] [and others

2000-01-01

To describe the MR imaging and clinical findings of spontaneous spinal epidural hematoma. The MR and clinical findings in six patients (M:F=3D4:2;adult:child=3D3:3) with spontaneous spinal epidural hematoma were reviewed. Five patients without any predisposing factor which might cause the condition and one with acute myelogenous leukemia were included. Emergency surgery was performed in two patients, and the other four were managed conservatively. The epidural lesion involved between three and seven vertebrae (mean:4.5), and relative to the spinal cord was located in the posterior-lateral (n=3D4), anterior (n=3D1), or right lateral (n=3D1) area. The hematoma was isointense (n=3D1) or hyperintense (n=3D5) with spinal cord on T1-weighted images, and hypointense (n=3D2) or hyperintense (n=3D4) on T2-weighted images. It was completely absorbed in four of five patients who underwent follow-up MR imaging, but not changed in one. The clinical outcome of these patients was complete recovery (n=3D4), spastic cerebral palsy (n=3D1), or unknown (n=3D1). Because of the lesion's characteristic signal intensity; MR imaging is very useful in the diagnosis and evaluation of spontaneous spinal epidural hematoma. (author)

Evaluation of parathyroid imaging methods with {sup 99m}Tc-MIBI. The comparison of planar images obtained using a pinhole collimator and a parallel-hole collimator

Energy Technology Data Exchange (ETDEWEB)

Fujii, Hirofumi; Iwasaki, Ryuichiro; Hashimoto, Jun; Nakamura, Kayoko; Kunieda, Etsuo; Sanmiya, Toshikazu; Kubo, Atsushi [Keio Univ., Tokyo (Japan). School of Medicine; Ogawa, Koichi; Inagaki, Kazutoshi

1999-07-01

Parathyroid scintigraphy with {sup 99m}Tc-MIBI was performed using two kinds of collimators, namely, a pinhole one and a parallel-hole one, to evaluate which one was more suitable for the detection of hyperfunctioning parathyroid lesions. In the studies using {sup 99m}Tc source, the pinhole collimator showed better efficiency and spatial resolution in the distance where the parathyroid scan are actually performed. In the phantom study, the nodular activities modeling parathyroid lesions were visualized better on the images obtained using the pinhole collimator. In clinical studies for 30 patients suspicious of hyperparathyroidism, hyperfunctioning parathyroid nodules were better detected when the pinhole collimator was used. In conclusion, the pinhole collimator was thought to be more suitable for parathyroid scintigraphy with {sup 99m}Tc-MIBI than the parallel-hole collimator. (author)

Tc-99m-diethyl-IDA imaging: clinical evaluation in jaundiced patients

International Nuclear Information System (INIS)

Pauwels, S.; Piret, L.; Schoutens, A.; Vandermoten, G.; Beckers, C.

1980-01-01

Hepatobiliary imaging with Tc-99m-N,α-(2,6-diethylacetanilide)-iminodiacetic acid (Tc-diethyl-IDA) was performed in 91 jaundiced patients with documented hepatobiliary damage and serum total bilirubin up to 35 mg/dl. There were 56 patients with obstructive jaundice and 35 with hepatocellular disease. Correct discrimination between hepatocellular and obstructive jaundice was possible with an overall accuracy of 90%. Agreement with the final clinical diagnosis was obtained in 97% of patients with hepatocellular disease, and in 86% of patients with obstructive jaundice. The reliability of the test was inversely related to the serum bilirubin levels below 10 mg/dl to 83% for bilirubin between 10 and 20 mg/dl. Above 20 mg/dl, the demonstration of a mechanical obstruction was possible in only one out of the four patients with obstructive jaundice. The high predictive values of the test illustrate that Tc-diethyl-IDA imaging constitutes a reliable method to demonstrate an obstructive cause for the jaundice as long as the bilirubin level remains below 20 mg/dl

Clinical use of gadobutrol for contrast-enhanced magnetic resonance imaging of neurological diseases

Directory of Open Access Journals (Sweden)

Cheng KT

2012-02-01

Full Text Available Kenneth T Cheng1, Hannah Y Cheng2, Kam Leung31Department of Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA; 2Freelance Technical Writer, New Orleans, LA, USA; 3National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USAAbstract: Contrast-enhanced magnetic resonance imaging (CE-MRI is an important clinical tool for diagnosing neurological diseases. The appropriate use of a suitable MRI contrast agent or contrast pharmaceutical is essential for CE-MRI to produce desirable diagnostic images. Currently, there are seven contrast agents (CAs or pharmaceuticals approved for clinical imaging of the central nervous system (CNS in the US, Europe, or Japan. All of the clinically approved CAs are water-soluble gadolinium-based contrast agents (GBCAs which do not penetrate the CNS blood–brain barrier (BBB. These agents are used for imaging CNS areas without a BBB, or various pathologies, such as tumors and infection that break down the BBB and allow CAs to enter into the surrounding parenchyma. Clinically, GBCAs are most useful for detecting primary and secondary cerebral neoplastic lesions. Among these CNS GBCAs, gadobutrol (Gd-BT-DO3A, Gadovist™ is a neutral, nonionic, macrocyclic compound that showed promising results from clinical trials of CNS imaging. In comparison with other GBCAs, Gd-BT-DO3A has relatively high in vitro kinetic stability and r1 relaxivity. Gd-BT-DO3A has been recently approved by the US Food and Drug Administration (FDA in 2011 for CNS imaging. A review of available literature shows that Gd-BT-DO3A exhibits similar safety and clinical efficacy profiles to other GBCAs. Gd-BT-DO3A has the distinguishing feature that it is the only clinical agent commercially available in a formulation of 1.0 M concentration with a relatively higher in vitro T1 shortening per unit volume than other clinical GBCAs which are only

A clinical gamma camera-based pinhole collimated system for high resolution small animal SPECT imaging

Energy Technology Data Exchange (ETDEWEB)

Mejia, J.; Galvis-Alonso, O.Y., E-mail: mejia_famerp@yahoo.com.b [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Dept. de Biologia Molecular; Castro, A.A. de; Simoes, M.V. [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Dept. de Clinica Medica; Leite, J.P. [Universidade de Sao Paulo (FMRP/USP), Ribeirao Preto, SP (Brazil). Fac. de Medicina. Dept. de Neurociencias e Ciencias do Comportamento; Braga, J. [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Div. de Astrofisica

2010-11-15

The main objective of the present study was to upgrade a clinical gamma camera to obtain high resolution tomographic images of small animal organs. The system is based on a clinical gamma camera to which we have adapted a special-purpose pinhole collimator and a device for positioning and rotating the target based on a computer-controlled step motor. We developed a software tool to reconstruct the target's three-dimensional distribution of emission from a set of planar projections, based on the maximum likelihood algorithm. We present details on the hardware and software implementation. We imaged phantoms and heart and kidneys of rats. When using pinhole collimators, the spatial resolution and sensitivity of the imaging system depend on parameters such as the detector-to-collimator and detector-to-target distances and pinhole diameter. In this study, we reached an object voxel size of 0.6 mm and spatial resolution better than 2.4 and 1.7 mm full width at half maximum when 1.5- and 1.0-mm diameter pinholes were used, respectively. Appropriate sensitivity to study the target of interest was attained in both cases. Additionally, we show that as few as 12 projections are sufficient to attain good quality reconstructions, a result that implies a significant reduction of acquisition time and opens the possibility for radiotracer dynamic studies. In conclusion, a high resolution single photon emission computed tomography (SPECT) system was developed using a commercial clinical gamma camera, allowing the acquisition of detailed volumetric images of small animal organs. This type of system has important implications for research areas such as Cardiology, Neurology or Oncology. (author)

The potential use of ultra-low radiation dose images in digital mammography-a clinical proof-of-concept study in craniocaudal views

NARCIS (Netherlands)

Bluekens, A. M. J.; Veldkamp, W. J. H.; Schuur, K. H.; Karssemeijer, N.; Broeders, M. J. M.; den Heeten, G. J.

2015-01-01

Objective: To estimate the potential of low-dose images in digital mammography by analysing the effect of substantial dose reduction in craniocaudal (CC) views on clinical performance. Methods: At routine mammography, additional CC views were obtained with about 10% of the standard dose. Five

The potential use of ultra-low radiation dose images in digital mammography--a clinical proof-of-concept study in craniocaudal views

NARCIS (Netherlands)

Bluekens, A.M.; Veldkamp, W.J.H.; Schuur, K.H.; Karssemeijer, N.; Broeders, M.J.; Heeten, GJ. den

2015-01-01

OBJECTIVE: To estimate the potential of low-dose images in digital mammography by analysing the effect of substantial dose reduction in craniocaudal (CC) views on clinical performance. METHODS: At routine mammography, additional CC views were obtained with about 10% of the standard dose. Five

Ultrasound-guided image fusion with computed tomography and magnetic resonance imaging. Clinical utility for imaging and interventional diagnostics of hepatic lesions

International Nuclear Information System (INIS)

Clevert, D.A.; Helck, A.; Paprottka, P.M.; Trumm, C.; Reiser, M.F.; Zengel, P.

2012-01-01

Abdominal ultrasound is often the first-line imaging modality for assessing focal liver lesions. Due to various new ultrasound techniques, such as image fusion, global positioning system (GPS) tracking and needle tracking guided biopsy, abdominal ultrasound now has great potential regarding detection, characterization and treatment of focal liver lesions. Furthermore, these new techniques will help to improve the clinical management of patients before and during interventional procedures. This article presents the principle and clinical impact of recently developed techniques in the field of ultrasound, e.g. image fusion, GPS tracking and needle tracking guided biopsy and discusses the results based on a feasibility study on 20 patients with focal hepatic lesions. (orig.) [de

Characterizing the inflammatory tissue response to acute myocardial infarction by clinical multimodality noninvasive imaging.

Science.gov (United States)

Wollenweber, Tim; Roentgen, Philipp; Schäfer, Andreas; Schatka, Imke; Zwadlo, Caroline; Brunkhorst, Thomas; Berding, Georg; Bauersachs, Johann; Bengel, Frank M

2014-09-01

Myocardial infarction (MI) triggers a systemic inflammatory response which determines subsequent healing. Experimentally, cardiac positron emission tomography and magnetic resonance imaging have been used successfully to obtain mechanistic insights. We explored the translational potential in patients early after MI. Positron emission tomography/computed tomography and cardiac magnetic resonance were performed in 15 patients sources of inflammatory cells. Positron emission tomography and cardiac magnetic resonance multimodality characterization of the acutely infarcted, inflamed myocardium may provide multiparametric end points for clinical studies aiming at support of infarct healing. © 2014 American Heart Association, Inc.

Imaging efficacy of a targeted imaging agent for fluorescence endoscopy

Science.gov (United States)

Healey, A. J.; Bendiksen, R.; Attramadal, T.; Bjerke, R.; Waagene, S.; Hvoslef, A. M.; Johannesen, E.

2008-02-01

Colorectal cancer is a major cause of cancer death. A significant unmet clinical need exists in the area of screening for earlier and more accurate diagnosis and treatment. We have identified a fluorescence imaging agent targeted to an early stage molecular marker for colorectal cancer. The agent is administered intravenously and imaged in a far red imaging channel as an adjunct to white light endoscopy. There is experimental evidence of preclinical proof of mechanism for the agent. In order to assess potential clinical efficacy, imaging was performed with a prototype fluorescence endoscope system designed to produce clinically relevant images. A clinical laparoscope system was modified for fluorescence imaging. The system was optimised for sensitivity. Images were recorded at settings matching those expected with a clinical endoscope implementation (at video frame rate operation). The animal model was comprised of a HCT-15 xenograft tumour expressing the target at concentration levels expected in early stage colorectal cancer. Tumours were grown subcutaneously. The imaging agent was administered intravenously at a dose of 50nmol/kg body weight. The animals were killed 2 hours post administration and prepared for imaging. A 3-4mm diameter, 1.6mm thick slice of viable tumour was placed over the opened colon and imaged with the laparoscope system. A receiver operator characteristic analysis was applied to imaging results. An area under the curve of 0.98 and a sensitivity of 87% [73, 96] and specificity of 100% [93, 100] were obtained.

Evaluation of random errors in Williams’ series coefficients obtained with digital image correlation

International Nuclear Information System (INIS)

Lychak, Oleh V; Holyns’kiy, Ivan S

2016-01-01

The use of the Williams’ series parameters for fracture analysis requires valid information about their error values. The aim of this investigation is the development of the method for estimation of the standard deviation of random errors of the Williams’ series parameters, obtained from the measured components of the stress field. Also, the criteria for choosing the optimal number of terms in the truncated Williams’ series for derivation of their parameters with minimal errors is proposed. The method was used for the evaluation of the Williams’ parameters, obtained from the data, and measured by the digital image correlation technique for testing a three-point bending specimen. (paper)

Challenges in clinical studies with multiple imaging probes

International Nuclear Information System (INIS)

Krohn, Kenneth A.; O'Sullivan, Finbarr; Crowley, John; Eary, Janet F.; Linden, Hannah M.; Link, Jeanne M.; Mankoff, David A.; Muzi, Mark; Rajendran, Joseph G.; Spence, Alexander M.; Swanson, Kristin R.

2007-01-01

This article addresses two related issues: (a) When a new imaging agent is proposed, how does the imager integrate it with other biomarkers, either sampled or imaged? (b) When we have multiple imaging agents, is the information additive or duplicative and how is this objectively determined? Molecular biology is leading to new treatment options with reduced normal tissue toxicity, and imaging should have a role in objectively evaluating new treatments. There are two roles for molecular characterization of disease. Molecular imaging measurements before therapy help predict the aggressiveness of disease and identify therapeutic targets and, therefore, help choose the optimal therapy for an individual. Measurements of specific biochemical processes made during or after therapy should be sensitive measures of tumor response. The rules of evidence are not fully developed for the prognostic role of imaging biomarkers, but the potential of molecular imaging provides compelling motivation to push forward with convincing validation studies. New imaging procedures need to be characterized for their effectiveness under realistic clinical conditions to improve the management of patients and achieve a better outcome. The purpose of this article is to promote a critical discussion within the molecular imaging community because our future value to the overall biomedical community will be in supporting better treatment outcomes rather than in detection

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.)

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.)

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.

A time-gated near-infrared spectroscopic imaging device for clinical applications.

Science.gov (United States)

Poulet, Patrick; Uhring, Wilfried; Hanselmann, Walter; Glazenborg, René; Nouizi, Farouk; Zint, Virginie; Hirschi, Werner

2013-03-01

A time-resolved, spectroscopic, diffuse optical tomography device was assembled for clinical applications like brain functional imaging. The entire instrument lies in a unique setup that includes a light source, an ultrafast time-gated intensified camera and all the electronic control units. The light source is composed of four near infrared laser diodes driven by a nanosecond electrical pulse generator working in a sequential mode at a repetition rate of 100 MHz. The light pulses are less than 80 ps FWHM. They are injected in a four-furcated optical fiber ended with a frontal light distributor to obtain a uniform illumination spot directed towards the head of the patient. Photons back-scattered by the subject are detected by the intensified CCD camera. There are resolved according to their time of flight inside the head. The photocathode is powered by an ultrafast generator producing 50 V pulses, at 100 MHz and a width corresponding to a 200 ps FWHM gate. The intensifier has been specially designed for this application. The whole instrument is controlled by an FPGA based module. All the acquisition parameters are configurable via software through an USB plug and the image data are transferred to a PC via an Ethernet link. The compactness of the device makes it a perfect device for bedside clinical applications. The instrument will be described and characterized. Preliminary data recorded on test samples will be presented.

Prospective clinical evaluation of an electronic portal imaging device

International Nuclear Information System (INIS)

Michalski, Jeff M.; Graham, Mary V.; Bosch, Walter R.; Wong, John; Gerber, Russell L.; Cheng, Abel; Tinger, Alfred; Valicenti, Richard K.

1996-01-01

Purpose: To determine whether the clinical implementation of an electronic portal imaging device can improve the precision of daily external beam radiotherapy. Methods and Materials: In 1991, an electronic portal imaging device was installed on a dual energy linear accelerator in our clinic. After training the radiotherapy technologists in the acquisition and evaluation of portal images, we performed a randomized study to determine whether online observation, interruption, and intervention would result in more precise daily setup. The patients were randomized to one of two groups: those whose treatments were actively monitored by the radiotherapy technologists and those that were imaged but not monitored. The treating technologists were instructed to correct the following treatment errors: (a) field placement error (FPE) > 1 cm; (b) incorrect block; (c) incorrect collimator setting; (d) absent customized block. Time of treatment delivery was recorded by our patient tracking and billing computers and compared to a matched set of patients not participating in the study. After the patients radiation therapy course was completed, an offline analysis of the patient setup error was planned. Results: Thirty-two patients were treated to 34 anatomical sites in this study. In 893 treatment sessions, 1,873 fields were treated (1,089 fields monitored and 794 fields unmonitored). Ninety percent of the treated fields had at least one image stored for offline analysis. Eighty-seven percent of these images were analyzed offline. Of the 1,011 fields imaged in the monitored arm, only 14 (1.4%) had an intervention recorded by the technologist. Despite infrequent online intervention, offline analysis demonstrated that the incidence of FPE > 10 mm in the monitored and unmonitored groups was 56 out of 881 (6.1%) and 95 out of 595 (11.2%), respectively; p 10 mm was confined to the pelvic fields. The time to treat patients in this study was 10.78 min (monitored) and 10.10 min (unmonitored

Evolution of modern nuclear medicine tumor-imaging diagnostics in clinical oncology

International Nuclear Information System (INIS)

Piperkova, E.

2000-01-01

The evolution of current nuclear medicine diagnostic is closely related to the technical progress in imaging equipment development, and application of radiopharmaceuticals (Rphs) with a different tumor-uptake mechanism. It is the aim of the study to present groups of tumor-imaging Rphs differing by tumor uptake mechanisms, used in clinical oncology. The obtained results are described, and compared with the ones reported by other researchers. Sensitivity and specificity of Rphs for cardio-scintigraphy with 99m Tc - MIBI and 201 Tl are relatively high, amounting to 93.7% and 60% respectively, in the various tumors. These indicators depend on the stage, location, histopathology, level of malignancy and biological activity of the neoplasm. 99m Tc - MIBI scintigraphy is endowed with considerable diagnostic potential for assaying multiple drug resistance (MDR), and is also a good criterion for its elimination following anti-MDR therapy. The obtained results show that radioimmunoscintigraphy (RIS) using different radiolabeled monoclonal antibodies (MoAb) have high sensitivity and specificity respectively: 86% and 80% in ovarian carcinoma with B72.3 antiTAG; 68.6% and 92.5% in colorectal carcinoma with B73.2 antiTAG, antiCEA, antiCA 19-9; 92% and 83% in breast cancer with antiCEA, 86.8% and 67-69% in malignant melanoma with 225.28s. Receptor scintigraphy may reach up to 86% sensitivity and 100% specificity in tumors saturated with somatostatin receptors. Positron emission tomography (PET) with 18F-FDG enhances the metabolic activity of tumor cells, and attains tumor-detecting rate amounting to 97%. Tumor imaging evolution characterized by the introduction and practical implementation of different Rphs, visualizing the functional and biochemical activity of tumor cells in the primary neoplasm, sentinel lymph nodes and distant metastases. radiolabelling of a variety of new biochemical substances, including DNA and RNA, drugs and lysosomes contributes to a successful imaging

Reliability of fish size estimates obtained from multibeam imaging sonar

Science.gov (United States)

Hightower, Joseph E.; Magowan, Kevin J.; Brown, Lori M.; Fox, Dewayne A.

2013-01-01

Multibeam imaging sonars have considerable potential for use in fisheries surveys because the video-like images are easy to interpret, and they contain information about fish size, shape, and swimming behavior, as well as characteristics of occupied habitats. We examined images obtained using a dual-frequency identification sonar (DIDSON) multibeam sonar for Atlantic sturgeon Acipenser oxyrinchus oxyrinchus, striped bass Morone saxatilis, white perch M. americana, and channel catfish Ictalurus punctatus of known size (20–141 cm) to determine the reliability of length estimates. For ranges up to 11 m, percent measurement error (sonar estimate – total length)/total length × 100 varied by species but was not related to the fish's range or aspect angle (orientation relative to the sonar beam). Least-square mean percent error was significantly different from 0.0 for Atlantic sturgeon (x̄  =  −8.34, SE  =  2.39) and white perch (x̄  = 14.48, SE  =  3.99) but not striped bass (x̄  =  3.71, SE  =  2.58) or channel catfish (x̄  = 3.97, SE  =  5.16). Underestimating lengths of Atlantic sturgeon may be due to difficulty in detecting the snout or the longer dorsal lobe of the heterocercal tail. White perch was the smallest species tested, and it had the largest percent measurement errors (both positive and negative) and the lowest percentage of images classified as good or acceptable. Automated length estimates for the four species using Echoview software varied with position in the view-field. Estimates tended to be low at more extreme azimuthal angles (fish's angle off-axis within the view-field), but mean and maximum estimates were highly correlated with total length. Software estimates also were biased by fish images partially outside the view-field and when acoustic crosstalk occurred (when a fish perpendicular to the sonar and at relatively close range is detected in the side lobes of adjacent beams). These sources of

NMR imaging

International Nuclear Information System (INIS)

Andrew, E.R.

1983-01-01

Since hydrogen is the most abundant element in all living organisms, proton NMR lends itself well as a method of investigation in biology and medicine. NMR imaging has some special advantages as a diagnostic tool: no ionizing radiation is used, it is noninvasive; it provides a safer means of imaging than the use of x-rays, gamma rays, positrons, or heavy ions. In contrast with ultrasound, the radiation penetrates the bony structures without attenuation. In additional to morphological information, NMR imaging provides additional diagnostic insights through relaxation parameters, which are not available from other imaging methods. In the decade since the first primitive NMR images were obtained, the quality of images now obtained approaches those from CT x-ray scanners. Prototype instruments are being constructed for clinical evaluation and the first whole-body scanners are beginning to appear on the market at costs comparable to CT scanners. Primary differences in equipment for conventional NMR and NMR imaging are the much larger aperture magnets that are required for the examination of human subjects and the addition of coils to generate field gradients and facilities for manipulating the gradients. Early results from clinical trials in many parts of the world are encouraging, and in a few years, the usefuleness of this modality of medical imaging to the medical profession in diagnosis and treatment of disease will be defined. 10 figures

Clinical evaluation of synthetic aperture harmonic imaging for scanning focal malignant liver lesions

DEFF Research Database (Denmark)

Brandt, Andreas Hjelm; Hemmsen, Martin Christian; Hansen, Peter Møller

2015-01-01

The purpose of the study was to perform a clinical comparison of synthetic aperture sequential beamformingtissue harmonic imaging (SASB-THI) sequences with a conventional imaging technique, dynamic receivefocusing with THI (DRF-THI). Both techniques used pulse inversion and were recorded interlea......The purpose of the study was to perform a clinical comparison of synthetic aperture sequential beamformingtissue harmonic imaging (SASB-THI) sequences with a conventional imaging technique, dynamic receivefocusing with THI (DRF-THI). Both techniques used pulse inversion and were recorded...

Virtual phantom magnetic resonance imaging (ViP MRI) on a clinical MRI platform.

Science.gov (United States)

Saint-Jalmes, Hervé; Bordelois, Alejandro; Gambarota, Giulio

2018-01-01

The purpose of this study was to implement Virtual Phantom Magnetic Resonance Imaging (ViP MRI), a technique that allows for generating reference signals in MR images using radiofrequency (RF) signals, on a clinical MR system and to test newly designed virtual phantoms. MRI experiments were conducted on a 1.5 T MRI scanner. Electromagnetic modelling of the ViP system was done using the principle of reciprocity. The ViP RF signals were generated using a compact waveform generator (dimensions of 26 cm × 18 cm × 16 cm), connected to a homebuilt 25 mm-diameter RF coil. The ViP RF signals were transmitted to the MRI scanner bore, simultaneously with the acquisition of the signal from the object of interest. Different types of MRI data acquisition (2D and 3D gradient-echo) as well as different phantoms, including the Shepp-Logan phantom, were tested. Furthermore, a uniquely designed virtual phantom - in the shape of a grid - was generated; this newly proposed phantom allows for the investigations of the vendor distortion correction field. High quality MR images of virtual phantoms were obtained. An excellent agreement was found between the experimental data and the inverse cube law, which was the expected functional dependence obtained from the electromagnetic modelling of the ViP system. Short-term time stability measurements yielded a coefficient of variation in the signal intensity over time equal to 0.23% and 0.13% for virtual and physical phantom, respectively. MR images of the virtual grid-shaped phantom were reconstructed with the vendor distortion correction; this allowed for a direct visualization of the vendor distortion correction field. Furthermore, as expected from the electromagnetic modelling of the ViP system, a very compact coil (diameter ~ cm) and very small currents (intensity ~ mA) were sufficient to generate a signal comparable to that of physical phantoms in MRI experiments. The ViP MRI technique was successfully implemented on a clinical MR

Effect of image resolution manipulation in rearfoot angle measurements obtained with photogrammetry.

Science.gov (United States)

Sacco, I C N; Picon, A P; Ribeiro, A P; Sartor, C D; Camargo-Junior, F; Macedo, D O; Mori, E T T; Monte, F; Yamate, G Y; Neves, J G; Kondo, V E; Aliberti, S

2012-09-01

The aim of this study was to investigate the influence of image resolution manipulation on the photogrammetric measurement of the rearfoot static angle. The study design was that of a reliability study. We evaluated 19 healthy young adults (11 females and 8 males). The photographs were taken at 1536 pixels in the greatest dimension, resized into four different resolutions (1200, 768, 600, 384 pixels) and analyzed by three equally trained examiners on a 96-pixels per inch (ppi) screen. An experienced physiotherapist marked the anatomic landmarks of rearfoot static angles on two occasions within a 1-week interval. Three different examiners had marked angles on digital pictures. The systematic error and the smallest detectable difference were calculated from the angle values between the image resolutions and times of evaluation. Different resolutions were compared by analysis of variance. Inter- and intra-examiner reliability was calculated by intra-class correlation coefficients (ICC). The rearfoot static angles obtained by the examiners in each resolution were not different (P > 0.05); however, the higher the image resolution the better the inter-examiner reliability. The intra-examiner reliability (within a 1-week interval) was considered to be unacceptable for all image resolutions (ICC range: 0.08-0.52). The whole body image of an adult with a minimum size of 768 pixels analyzed on a 96-ppi screen can provide very good inter-examiner reliability for photogrammetric measurements of rearfoot static angles (ICC range: 0.85-0.92), although the intra-examiner reliability within each resolution was not acceptable. Therefore, this method is not a proper tool for follow-up evaluations of patients within a therapeutic protocol.

Utilizing data grid architecture for the backup and recovery of clinical image data.

Science.gov (United States)

Liu, Brent J; Zhou, M Z; Documet, J

2005-01-01

Grid Computing represents the latest and most exciting technology to evolve from the familiar realm of parallel, peer-to-peer and client-server models. However, there has been limited investigation into the impact of this emerging technology in medical imaging and informatics. In particular, PACS technology, an established clinical image repository system, while having matured significantly during the past ten years, still remains weak in the area of clinical image data backup. Current solutions are expensive or time consuming and the technology is far from foolproof. Many large-scale PACS archive systems still encounter downtime for hours or days, which has the critical effect of crippling daily clinical operations. In this paper, a review of current backup solutions will be presented along with a brief introduction to grid technology. Finally, research and development utilizing the grid architecture for the recovery of clinical image data, in particular, PACS image data, will be presented. The focus of this paper is centered on applying a grid computing architecture to a DICOM environment since DICOM has become the standard for clinical image data and PACS utilizes this standard. A federation of PACS can be created allowing a failed PACS archive to recover its image data from others in the federation in a seamless fashion. The design reflects the five-layer architecture of grid computing: Fabric, Resource, Connectivity, Collective, and Application Layers. The testbed Data Grid is composed of one research laboratory and two clinical sites. The Globus 3.0 Toolkit (Co-developed by the Argonne National Laboratory and Information Sciences Institute, USC) for developing the core and user level middleware is utilized to achieve grid connectivity. The successful implementation and evaluation of utilizing data grid architecture for clinical PACS data backup and recovery will provide an understanding of the methodology for using Data Grid in clinical image data backup for

A comparison of clinical symptoms and magnetic resonance images in temporomandibular joint disorders

Energy Technology Data Exchange (ETDEWEB)

Choi, Yong Suk; Hwang, Eui Hwan; Lee, Sang Rae [Kyunghee University College of Medicine, Seoul (Korea, Republic of)

2003-06-15

To determine the relationship between clinical symptoms and magnetic resonance (MR) images in patients presenting with temporomandibular joint (TMJ) disorders. This study was based on 172 joints in 86 patients presenting with TMJ disorders. Joint pain and sound during jaw opening and closing movements were recorded, and the possible relationship between disc positions and bony changes of the condylar head and the articular fossa in MR images in the oblique sagittal planes were examined. Data were analyzed by Chi-square test. There was no statistically significant relationship between clinical symptoms and MR images in the patients with TMJ disorders. In the patient with TMJ disorders, joint pain and sound could not be specific clinical symptoms that are related with MR image findings, and asymptomatic joint did not necessarily imply that the joints are normal according to MR image findings.

Imaging manifestations and its clinical significance in patients with oncogenic osteomalacia

International Nuclear Information System (INIS)

Yu Wei; Lin Qiang; Zhang Yunqing; Jiang Bo; Jin Jin; Jiang Yan; Li Mei; Li Fang

2006-01-01

Objective: To compare images from different modality for detecting lesions in patients with oncogenic osteomalacia. Methods: Eight patients with oncogenic osteomalacia were recruited in this study. The age ranged from 28 to 69 years (mean age 44.1, 5 men and 3 women). All patients were diagnosed as osteomalacia according to their clinical and radiographic manifestations. Main laboratory tests included serum calcium, phosphorus, alkaline phosphatase activity, parathyroid hormone, urinary phosphorus as well as liver and renal functions. Octreotide scans were performed for all patients according to clinical request for confirming the oncogenic osteomalacia. Further examinations of MR imaging in 8 patients, spiral CT in four patients and conventional radiography in four patients were obtained after the octreotide scans respectively. All patients had operation for their tumor resections and for the pathologic diagnostic findings. Results: Abnormal laboratory findings in all patients included low serum phosphorus level (ranged from 0.29 to 0.65 mmol·L -1 ), elevated alkaline phosphatase activity (ranged from 36. 6 to 310.6 μmol·s -1 ·L -1 ) as well as urinary phosphorus level (ranged from 11.5 to 40. 9 mmol·L -1 ). Normal results included parathyroid hormone level, liver and renal functions. Pathology confirmed the diagnosis of 4 soft tissue tumors including 1 hemangiomas, 1 giant-cell tumor of tendon sheath, 1 hemangiopericytoma and 1 mesenchymal tumor, as well as 4 bone tumors including 1 malignant neurofibroma, 2 mesenchymal tumors and 1 fibroblastoma. All lesions were shown abnormal region of increasing uptake tracer on octreotide scans. However, the octreotide scans could not determine where (bone or soft tissues) the lesions located. MR imaging could differentiate the lesions within the bone or within the soft tissues in all patients. All lesions had hypo- or iso- signal intensity on T 1 WI and high signal intensity on T 2 WI with heterogeneous in 6 tumors and

Imaging of cystic fibrosis lung disease and clinical interpretation

Energy Technology Data Exchange (ETDEWEB)

Wielpuetz, M.O.; Eichinger, M.; Kauczor, H.U. [Heidelberg University Hospital (Germany). Dept. of Diagnostic and Interventional Radiology; Translational Lung Research Center Heidelberg (TLRC) (Germany); Heidelberg University Hospital (Germany). Dept. of Diagnostic and Interventional Radiology with Nuclear Medicine; Biederer, J. [Heidelberg University Hospital (Germany). Dept. of Diagnostic and Interventional Radiology; Translational Lung Research Center Heidelberg (TLRC) (Germany); Gross-Gerau Community Hospital (Germany). Radiologie Darmstadt; Wege, S. [Heidelberg University Hospital (Germany). Dept. of Pulmonology and Respiratory Medicine; Stahl, M.; Sommerburg, O. [Translational Lung Research Center Heidelberg (TLRC) (Germany); Heidelberg University Hospital (Germany). Div. of Pediatric Pulmonology and Allergy and Cystic Fibrosis Center; Mall, M.A. [Translational Lung Research Center Heidelberg (TLRC) (Germany); Heidelberg University Hospital (Germany). Div. of Pediatric Pulmonology and Allergy and Cystic Fibrosis Center; Heidelberg University Hospital (Germany). Dept. of Translational Pulmonology; Puderbach, M. [Heidelberg University Hospital (Germany). Dept. of Diagnostic and Interventional Radiology; Translational Lung Research Center Heidelberg (TLRC) (Germany); Heidelberg University Hospital (Germany). Dept. of Diagnostic and Interventional Radiology with Nuclear Medicine; Hufeland Hospital, Bad Langensalza (Germany). Dept. of Diagnostic and Interventional Radiology

2016-09-15

Progressive lung disease in cystic fibrosis (CF) is the life-limiting factor of this autosomal recessive genetic disorder. Increasing implementation of CF newborn screening allows for a diagnosis even in pre-symptomatic stages. Improvements in therapy have led to a significant improvement in survival, the majority now being of adult age. Imaging provides detailed information on the regional distribution of CF lung disease, hence longitudinal imaging is recommended for disease monitoring in the clinical routine. Chest X-ray (CXR), computed tomography (CT) and magnetic resonance imaging (MRI) are now available as routine modalities, each with individual strengths and drawbacks, which need to be considered when choosing the optimal modality adapted to the clinical situation of the patient. CT stands out with the highest morphological detail and has often been a substitute for CXR for regular severity monitoring at specialized centers. Multidetector CT data can be post-processed with dedicated software for a detailed measurement of airway dimensions and bronchiectasis and potentially a more objective and precise grading of disease severity. However, changing to CT was inseparably accompanied by an increase in radiation exposure of CF patients, a young population with high sensitivity to ionizing radiation and lifetime accumulation of dose. MRI as a cross-sectional imaging modality free of ionizing radiation can depict morphological hallmarks of CF lung disease at lower spatial resolution but excels with comprehensive functional lung imaging, with time-resolved perfusion imaging currently being most valuable.

Imaging vascular function for early stage clinical trials using dynamic contrast-enhanced magnetic resonance imaging

Energy Technology Data Exchange (ETDEWEB)

Leach, M.O.; Orton, M. [Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Cancer Research UK and EPSRC Cancer Imaging Centre, Sutton, Surrey (United Kingdom); Morgan, B. [Univ. of Leicester, College of Medicine, Biological Sciences and Psychology, Leicester (United Kingdom); Tofts, P.S. [Brighton and Sussex Medical School, Univ. of Sussex, Clinical Imaging Sciences Centre, Sussex (United Kingdom); Buckley, D.L. [University of Leeds, Division of Medical Physics, Leeds (United Kingdom); Huang, W. [Oregon Health and Science Univ., Advanced Imaging Research Centre, Portland, OR (United States); Horsfield, M.A. [Medical Physics Section, Leicester Royal Infirmary, Dept. of Cardiovascular Sciences, Leicester (United Kingdom); Chenevert, T.L. [Univ. of Michigan Health System, Ann Arbor, MI (United States); Collins, D.J. [Royal Marsden Hospital NHS Foundation Trust, Cancer Research UK and EPSRC Cancer Imaging Centre, Sutton, Surrey (United Kingdom); Jackson, A. [Univ. of Manchester, Wolfson Molecular Imaging Centre, Withington, Manchester, M20 3LJ (United Kingdom); Lomas, D. [Univ. of Cambridge, Dept. of Radiology, Cambridge (United Kingdom); Whitcher, B. [Unit 2 Greenways Business Park, Mango Solutions, Chippenham (United Kingdom); Clarke, L. [Cancer Imaging Program, Imaging Technology Development Branch, Rockville, MD (United States); Plummer, R. [Univ. of Newcastle Upon Tyne, The Medical School, Medical Oncology, Northern Inst. for Cancer Research, Newcastle Upon Tyne (United Kingdom); Judson, I. [Royal Marsden Hospital, Sutton, Surrey (United Kingdom); Jones, R. [Beatson West of Scotland Cancer Centre, Glasgow (United Kingdom); Alonzi, R. [Mount Vernon Cancer Centre, Northwood (United Kingdom); Brunner, T. [Gray Inst. for Radiation, Oncology and Biology, Oxford (United Kingdom); Koh, D.M. [Royal Marsden NHS Foundation Trust, Diagnostic Radiology, Sutton, Surrey (United Kingdom)] [and others

2012-07-15

Many therapeutic approaches to cancer affect the tumour vasculature, either indirectly or as a direct target. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has become an important means of investigating this action, both pre-clinically and in early stage clinical trials. For such trials, it is essential that the measurement process (i.e. image acquisition and analysis) can be performed effectively and with consistency among contributing centres. As the technique continues to develop in order to provide potential improvements in sensitivity and physiological relevance, there is considerable scope for between-centre variation in techniques. A workshop was convened by the Imaging Committee of the Experimental Cancer Medicine Centres (ECMC) to review the current status of DCE-MRI and to provide recommendations on how the technique can best be used for early stage trials. This review and the consequent recommendations are summarised here. (orig.)

Fat-suppressed MR images of both hands obtained using CHESS can be improved by rice pads

Energy Technology Data Exchange (ETDEWEB)

Moriya, Susumu, E-mail: smoyari@yahoo.co.jp [Ishikawa Clinic, 46-1 Shimokamo-Umenoki-cho, Sakyo-ku, Kyoto-shi, Kyoto 606-0851 (Japan); Miki, Yukio [Department of Radiology, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585 (Japan); Kamishima, Tamotsu [Department of Biomedical Sciences and Engineering, Hokkaido University Graduate School of Health Science, North-12 West-5 Kita-ku, Sapporo 060-0812 (Japan); Kanagaki, Mitsunori [Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University, 54 Shogoin-kawahara-cho, Sakyo-ku, Kyoto-shi, Kyoto 606-8507 (Japan); Yokobayashi, Tsuneo; Ishikawa, Mitsunori [Ishikawa Clinic, 46-1 Shimokamo-Umenoki-cho, Sakyo-ku, Kyoto-shi, Kyoto 606-0851 (Japan)

2012-09-15

When chemical shift selective (CHESS) imaging is used with magnetic resonance imaging (MRI) for simultaneous imaging of both hands for the evaluation of rheumatoid arthritis, the fat suppression effect is poor. We investigated whether these fat-suppressed images using CHESS could be improved with the use of rice pads. T1-weighted images were obtained with CHESS and the same imaging parameters were used with and without rice pads on the coronal plane of both hands in 10 healthy volunteers. Patients were placed in a prone position with both hands extended overhead. The fat-suppression effect was classified into four categories and scored for both sets of images, and visual assessments were made by one radiologist and one radiologic technologist. The evaluation score was 1.1 for the images made without rice pads, and 3.2 for the images made with rice pads. The fat suppression effect was thus significantly better in the images made using rice pads (P < 0.0001). Lingering fat signals disappeared almost completely in images of both hands using CHESS with rice pads, and it was confirmed that the images were improved and had good fat suppression. More accurate evaluation of inflammatory sites that occur in rheumatoid arthritis may thus be possible, promising better diagnostic accuracy.

Fat-suppressed MR images of both hands obtained using CHESS can be improved by rice pads

International Nuclear Information System (INIS)

Moriya, Susumu; Miki, Yukio; Kamishima, Tamotsu; Kanagaki, Mitsunori; Yokobayashi, Tsuneo; Ishikawa, Mitsunori

2012-01-01

When chemical shift selective (CHESS) imaging is used with magnetic resonance imaging (MRI) for simultaneous imaging of both hands for the evaluation of rheumatoid arthritis, the fat suppression effect is poor. We investigated whether these fat-suppressed images using CHESS could be improved with the use of rice pads. T1-weighted images were obtained with CHESS and the same imaging parameters were used with and without rice pads on the coronal plane of both hands in 10 healthy volunteers. Patients were placed in a prone position with both hands extended overhead. The fat-suppression effect was classified into four categories and scored for both sets of images, and visual assessments were made by one radiologist and one radiologic technologist. The evaluation score was 1.1 for the images made without rice pads, and 3.2 for the images made with rice pads. The fat suppression effect was thus significantly better in the images made using rice pads (P < 0.0001). Lingering fat signals disappeared almost completely in images of both hands using CHESS with rice pads, and it was confirmed that the images were improved and had good fat suppression. More accurate evaluation of inflammatory sites that occur in rheumatoid arthritis may thus be possible, promising better diagnostic accuracy

Diagnostic Accuracy of Clinical Examination and Imaging Findings for Identifying Subacromial Pain.

Science.gov (United States)

Cadogan, Angela; McNair, Peter J; Laslett, Mark; Hing, Wayne A

2016-01-01

The diagnosis of subacromial pathology is limited by the poor accuracy of clinical tests for specific pathologies. The aim of this study was to estimate the diagnostic accuracy of clinical examination and imaging features for identifying subacromial pain (SAP) defined by a positive response to diagnostic injection, and to evaluate the influence of imaging findings on the clinical diagnosis of SAP. In a prospective, diagnostic accuracy design, 208 consecutive patients presenting to their primary healthcare practitioner for the first time with a new episode of shoulder pain were recruited. All participants underwent a standardized clinical examination, shoulder x-ray series and diagnostic ultrasound scan. Results were compared with the response to a diagnostic block of xylocaineTM injected into the SAB under ultrasound guidance using ≥80% post-injection reduction in pain intensity as the positive anaesthetic response (PAR) criterion. Diagnostic accuracy statistics were calculated for combinations of clinical and imaging variables demonstrating the highest likelihood of a PAR. A PAR was reported by 34% of participants. In participants with no loss of passive external rotation, combinations of three clinical variables (anterior shoulder pain, strain injury, absence of symptoms at end-range external rotation (in abduction)) demonstrated 100% specificity for a PAR when all three were positive (LR+ infinity; 95%CI 2.9, infinity). A full-thickness supraspinatus tear on ultrasound increased the likelihood of a PAR irrespective of age (specificity 98% (95%CI 94, 100); LR+ 6.2; 95% CI 1.5, 25.7)). Imaging did not improve the ability to rule-out a PAR. Combinations of clinical examination findings and a full-thickness supraspinatus tear on ultrasound scan can help confirm, but not exclude, the presence of subacromial pain. Other imaging findings were of limited value for diagnosing SAP.

Quantitative imaging of the human upper airway: instrument design and clinical studies

Science.gov (United States)

Leigh, M. S.; Armstrong, J. J.; Paduch, A.; Sampson, D. D.; Walsh, J. H.; Hillman, D. R.; Eastwood, P. R.

2006-08-01

Imaging of the human upper airway is widely used in medicine, in both clinical practice and research. Common imaging modalities include video endoscopy, X-ray CT, and MRI. However, no current modality is both quantitative and safe to use for extended periods of time. Such a capability would be particularly valuable for sleep research, which is inherently reliant on long observation sessions. We have developed an instrument capable of quantitative imaging of the human upper airway, based on endoscopic optical coherence tomography. There are no dose limits for optical techniques, and the minimally invasive imaging probe is safe for use in overnight studies. We report on the design of the instrument and its use in preliminary clinical studies, and we present results from a range of initial experiments. The experiments show that the instrument is capable of imaging during sleep, and that it can record dynamic changes in airway size and shape. This information is useful for research into sleep disorders, and potentially for clinical diagnosis and therapies.

Personalized Medicine: how to Switch from the Concept to the Integration into the Clinical Development Plan to Obtain Marketing Authorization.

Science.gov (United States)

Becquemont, Laurent; Bordet, Régis; Cellier, Dominic

2012-01-01

One of the challenges of the coming years is to personalize medicine in order to provide each patient with an individualized treatment plan. The three objectives of personalized medicine are to refine diagnosis, rationalize treatment and engage patients in a preventive approach. Personalization can be characterized by various descriptors whether related to the field, biology, imaging, type of lesion of the entity to be treated, comorbidity factors, coprescriptions or the environment As part of personalized medicine focused on biological markers including genetics or genomics, the integration of the clinical development plan to obtain marketing authorization may be segmented in 3 stages with a known descriptor identified before clinical development, a known descriptor discovered during clinical development or a known descriptor known after clinical development. For each stage, it is important to clearly define the technical optimization elements, to specify the expectations and objectives, to examine the methodological aspects of each clinical development phase and finally to consider the fast changing regulatory requirements in view of the few registered therapeutics complying with the definition of personalized medicine as well as the significant technological breakthroughs according to the screened and selected biomarkers. These considerations should be integrated in view of the time required for clinical development from early phase to MA, i.e. more than 10 years. Moreover, business models related to the economic environment should be taken into account when deciding whether or not to retain a biomarker allowing the selection of target populations in a general population. © 2012 Société Française de Pharmacologie et de Thérapeutique.

Clinical usefulness of delayed exercise images on 99mTc-tetrofosmin myocardial SPECT in the diagnosis of vasospastic angina pectoris

International Nuclear Information System (INIS)

Ito, Kazuki; Zen, Kan; Hikosaka, Takatou; Adachi, Yoshihiko; Yoneyama, Satoshi; Katoh, Shuuji; Sugihara, Hiroki; Nakamura, Tomoki; Azuma, Akihiro

2000-01-01

This study was designed to evaluate the clinical usefulness of delayed exercise images in 99m Tc-tetrofosmin (TF) myocardial SPECT in the diagnosis of vasospastic angina pectoris. We studied 30 patients with vasospastic angina, 10 of 30 patients (group A) had both effort and rest angina, 20 of 30 patients (group B) had rest angina. A 370 MBq of TF was intravenously injected at peak exercise, and initial (EX-I) and delayed exercise (EX-D) images were obtained at 30 min and 180 min after the injection. An additional 740 MBq of TF was intravenously reinjected after EX-D image acquisition, and rest images were obtained 30 min after the reinjection. The left ventricular wall was divided into 9 segments. Regional myocardial uptakes of TF were scored by 4-point defect score (0=normal, 1=mildly reduced, 2=moderately reduced, and 3=severely reduced). Total defect score (TDS) was calculated from the sum of defect scores in 9 segments. Reverse redistribution (RR) was defined as increase of more than 2 in TDS on EX-D images. In group A, 4 of 10 cases (40%) showed decreased uptake on EX-I images, 6 of 10 cases (60%) revealed RR on EX-D images, and none of the patients showed decreased uptake on rest images. In group B, no one showed decreased uptake on EX-I and rest images, 11 of 20 cases (55%) revealed RR on EX-D images. The mean±SD of TDS were 2.9±3.4, 5.1±4.5, 0.5±0.5 on EX-I, EX-D, rest images in group A, and serially 0.4±0.5, 3.3±3.6, 0.4±0.5 in group B. Regional wall motion abnormality was reduced in regions with RR. RR on EX-D images may reflect ischemic damaged but viable myocardium in vasospastic angina. The clinical usefulness of exercise-rest TF imaging in detection of organic coronary artery disease has been well established. Therefore, exercise-rest TF imaging with additional delayed exercise image could evaluate not only organic coronary artery disease but also coronary artery vasospasm. (author)

Clinical magnetic resonance: imaging and spectroscopy

International Nuclear Information System (INIS)

Andrew, E.R.; Bydder, Graeme; Griffiths, John; Iles, Richard; Styles, Peter

1990-01-01

This book begins with a readable, comprehensive but non-mathematical introduction to the basic underlying principles of magnetic resonance. Further chapters include information on the theory and principles of MRI and MRS, the interpretation of MR images, the clinical applications and scope of MRI and MRS, practical aspects of spectroscopy and magnetic resonance, and also the practical problems associated with the siting, safety and operation of large MRI and MRS equipment. (author)

Morphological and Functional Measurements of the Heart Obtained by Magnetic Resonance Imaging in Brazilians

Energy Technology Data Exchange (ETDEWEB)

Macedo, Robson, E-mail: robmacedo@yahoo.com [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil); Fernandes, Juliano Lara [Universidade Estadual de Campinas, Campinas, SP (Brazil); Andrade, Solange Souza; Rochitte, Carlos Eduardo [Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Lima, Kênio Costa; Maciel, Álvaro Campos Cavalcanti [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil); Maciel, Fernanda Cunha; Alves, Geraldo Souza Pinho [Universidade Potiguar, Natal, RN (Brazil); Coelho, Otávio Rizzi [Universidade Estadual de Campinas, Campinas, SP (Brazil); Diniz, Rosiane Viana Zuza [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil)

2013-07-15

Still today, measurements used as a reference in the cardiac magnetic resonance imaging have been obtained mainly from studies carried out in North-American and European populations. To obtain measurements of the diastolic diameter, systolic diameter, end diastolic volume, end systolic volume, ejection fraction, and myocardial mass of the left and right ventricles in Brazilians. 54 men and 53 women, with mean age of 43.4 ± 13.1 years, asymptomatic, with no cardiomyopathies, have been subjected to the cardiac magnetic resonance imaging, using a balanced steady state free precession technique. The averages and the standard deviations of the parameters for the left ventricle have been: diastolic diameter =4.8 ± 0.5 cm; systolic diameter = 3.0 ± 0.6 cm; end diastolic volume = 128.4 ± 29.6 mL; end systolic volume = 45.2 ± 16.6 mL; ejection fraction = 65.5 ± 6.3%; mass = 95.2 ± 30.8 g. For the right ventricle, they have been: diastolic diameter = 3.9 ± 1.3 cm; systolic diameter = 2.5 ± 0.5 cm; end diastolic volume = 126.5 ± 30.7 mL; end systolic volume = 53.6 ± 18.4 mL; ejection fraction = 58.3 ± 8.0%, and mass = 26.1 ± 6.1 g. The masses and the volumes were significantly greater in the men, except for the end systolic volume of the left ventricle. The ejection fraction of the right ventricle has been significantly greater in the women. There has been a significant and inverted correlation of the systolic volume of the right volume with the progression of the age. This study has described, for the first time, cardiac measurements obtained through the cardiac magnetic resonance imaging in Brazilians, asymptomatic, with no cardiomyopathies, showing differences in accordance with gender and age.

Morphological and Functional Measurements of the Heart Obtained by Magnetic Resonance Imaging in Brazilians

International Nuclear Information System (INIS)

Macedo, Robson; Fernandes, Juliano Lara; Andrade, Solange Souza; Rochitte, Carlos Eduardo; Lima, Kênio Costa; Maciel, Álvaro Campos Cavalcanti; Maciel, Fernanda Cunha; Alves, Geraldo Souza Pinho; Coelho, Otávio Rizzi; Diniz, Rosiane Viana Zuza

2013-01-01

Still today, measurements used as a reference in the cardiac magnetic resonance imaging have been obtained mainly from studies carried out in North-American and European populations. To obtain measurements of the diastolic diameter, systolic diameter, end diastolic volume, end systolic volume, ejection fraction, and myocardial mass of the left and right ventricles in Brazilians. 54 men and 53 women, with mean age of 43.4 ± 13.1 years, asymptomatic, with no cardiomyopathies, have been subjected to the cardiac magnetic resonance imaging, using a balanced steady state free precession technique. The averages and the standard deviations of the parameters for the left ventricle have been: diastolic diameter =4.8 ± 0.5 cm; systolic diameter = 3.0 ± 0.6 cm; end diastolic volume = 128.4 ± 29.6 mL; end systolic volume = 45.2 ± 16.6 mL; ejection fraction = 65.5 ± 6.3%; mass = 95.2 ± 30.8 g. For the right ventricle, they have been: diastolic diameter = 3.9 ± 1.3 cm; systolic diameter = 2.5 ± 0.5 cm; end diastolic volume = 126.5 ± 30.7 mL; end systolic volume = 53.6 ± 18.4 mL; ejection fraction = 58.3 ± 8.0%, and mass = 26.1 ± 6.1 g. The masses and the volumes were significantly greater in the men, except for the end systolic volume of the left ventricle. The ejection fraction of the right ventricle has been significantly greater in the women. There has been a significant and inverted correlation of the systolic volume of the right volume with the progression of the age. This study has described, for the first time, cardiac measurements obtained through the cardiac magnetic resonance imaging in Brazilians, asymptomatic, with no cardiomyopathies, showing differences in accordance with gender and age

Comparison of biometric measurements obtained by the Verion Image-Guided System versus the auto-refracto-keratometer.

Science.gov (United States)

Velasco-Barona, Cecilio; Cervantes-Coste, Guadalupe; Mendoza-Schuster, Erick; Corredor-Ortega, Claudia; Casillas-Chavarín, Nadia L; Silva-Moreno, Alejandro; Garza-León, Manuel; Gonzalez-Salinas, Roberto

2018-06-01

To compare the biometric measurements obtained from the Verion Image-Guided System to those obtained by auto-refracto-keratometer in normal eyes. This is a prospective, observational, comparative study conducted at the Asociación para Evitar la Ceguera en México I.A.P., Mexico. Three sets of keratometry measurements were obtained using the image-guided system to assess the coefficient of variation, the within-subject standard deviation and intraclass correlation coefficient (ICC). A paired Student t test was used to assess statistical significance between the Verion and the auto-refracto-keratometer. A Pearson's correlation coefficient (r) was obtained for all measurements, and the level of agreement was verified using Bland-Altman plots. The right eyes of 73 patients were evaluated by each platform. The Verion coefficient of variation was 0.3% for the flat and steep keratometry, with the ICC being greater than 0.9 for all parameters measured. Paired t test showed statistically significant differences between groups (P = 0.0001). A good correlation was evidenced for keratometry values between platforms (r = 0.903, P = 0.0001 for K1, and r = 0.890, P = 0.0001). Bland-Altman plots showed a wide data spread for all variables. The image-guided system provided highly repeatable corneal power and keratometry measurements. However, significant differences were evidenced between the two platforms, and although values were highly correlated, they showed a wide data spread for all analysed variables; therefore, their interchangeable use for biometry assessment is not advisable.

Evaluation of image quality and radiation dose using gold nanoparticles and other clinical contrast agents in dual-energy Computed Tomography (CT): CT abdomen phantom

Science.gov (United States)

Zukhi, J.; Yusob, D.; Tajuddin, A. A.; Vuanghao, L.; Zainon, R.

2017-05-01

The aim of this study was to evaluate the image quality and radiation dose using commercial gold nanoparticles and clinical contrast agents in dual-energy Computed Tomography (CT). Five polymethyl methacrylate (PMMA) tubes were used in this study, where four tubes were filled with different contrast agents (barium, iodine, gadolinium, and gold nanoparticles). The fifth tube was filled with water. Two optically stimulated luminescence dosimeters (OSLD) were placed in each tube to measure the radiation dose. The tubes were placed in a fabricated adult abdominal phantom of 32 cm in diameter using PMMA. The phantom was scanned using a DECT at low energy (80 kV) and high energy (140 kV) with different pitches (0.6 mm and 1.0 mm) and different slice thickness (3.0 mm and 5.0 mm). The tube current was applied automatically using automatic exposure control (AEC) and tube current modulation recommended by the manufacturer (CARE Dose 4D, Siemens, Germany). The contrast-to-noise ratio (CNR) of each contrast agent was analyzed using Weasis software. Gold nanoparticles has highest atomic number (Z = 79) than barium (Z = 56), iodine (Z = 53) and gadolinium (Z = 64). The CNR value of each contrast agent increases when the slice thickness increases. The radiation dose obtained from this study decreases when the pitch increases. The optimal imaging parameters for gold nanoparticles and other clinical contrast agents is obtained at pitch value of 1.0 mm and slice thickness of 5.0 mm. Low noise and low radiation dose obtained at these imaging parameters. The optimal imaging parameters obtained in this study can be applied in multiple contrast agents imaging.

Evaluation of image quality and radiation dose using gold nanoparticles and other clinical contrast agents in dual-energy Computed Tomography (CT): CT abdomen phantom

International Nuclear Information System (INIS)

Zukhi, J; Yusob, D; Vuanghao, L; Zainon, R; Tajuddin, A A

2017-01-01

The aim of this study was to evaluate the image quality and radiation dose using commercial gold nanoparticles and clinical contrast agents in dual-energy Computed Tomography (CT). Five polymethyl methacrylate (PMMA) tubes were used in this study, where four tubes were filled with different contrast agents (barium, iodine, gadolinium, and gold nanoparticles). The fifth tube was filled with water. Two optically stimulated luminescence dosimeters (OSLD) were placed in each tube to measure the radiation dose. The tubes were placed in a fabricated adult abdominal phantom of 32 cm in diameter using PMMA. The phantom was scanned using a DECT at low energy (80 kV) and high energy (140 kV) with different pitches (0.6 mm and 1.0 mm) and different slice thickness (3.0 mm and 5.0 mm). The tube current was applied automatically using automatic exposure control (AEC) and tube current modulation recommended by the manufacturer (CARE Dose 4D, Siemens, Germany). The contrast-to-noise ratio (CNR) of each contrast agent was analyzed using Weasis software. Gold nanoparticles has highest atomic number (Z = 79) than barium (Z = 56), iodine (Z = 53) and gadolinium (Z = 64). The CNR value of each contrast agent increases when the slice thickness increases. The radiation dose obtained from this study decreases when the pitch increases. The optimal imaging parameters for gold nanoparticles and other clinical contrast agents is obtained at pitch value of 1.0 mm and slice thickness of 5.0 mm. Low noise and low radiation dose obtained at these imaging parameters. The optimal imaging parameters obtained in this study can be applied in multiple contrast agents imaging. (paper)

Fat-suppressed MR images of both hands obtained using CHESS can be improved by rice pads.

Science.gov (United States)

Moriya, Susumu; Miki, Yukio; Kamishima, Tamotsu; Kanagaki, Mitsunori; Yokobayashi, Tsuneo; Ishikawa, Mitsunori

2012-09-01

When chemical shift selective (CHESS) imaging is used with magnetic resonance imaging (MRI) for simultaneous imaging of both hands for the evaluation of rheumatoid arthritis, the fat suppression effect is poor. We investigated whether these fat-suppressed images using CHESS could be improved with the use of rice pads. T1-weighted images were obtained with CHESS and the same imaging parameters were used with and without rice pads on the coronal plane of both hands in 10 healthy volunteers. Patients were placed in a prone position with both hands extended overhead. The fat-suppression effect was classified into four categories and scored for both sets of images, and visual assessments were made by one radiologist and one radiologic technologist. The evaluation score was 1.1 for the images made without rice pads, and 3.2 for the images made with rice pads. The fat suppression effect was thus significantly better in the images made using rice pads (PCHESS with rice pads, and it was confirmed that the images were improved and had good fat suppression. More accurate evaluation of inflammatory sites that occur in rheumatoid arthritis may thus be possible, promising better diagnostic accuracy. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Multiscale integration of -omic, imaging, and clinical data in biomedical informatics.

Science.gov (United States)

Phan, John H; Quo, Chang F; Cheng, Chihwen; Wang, May Dongmei

2012-01-01

This paper reviews challenges and opportunities in multiscale data integration for biomedical informatics. Biomedical data can come from different biological origins, data acquisition technologies, and clinical applications. Integrating such data across multiple scales (e.g., molecular, cellular/tissue, and patient) can lead to more informed decisions for personalized, predictive, and preventive medicine. However, data heterogeneity, community standards in data acquisition, and computational complexity are big challenges for such decision making. This review describes genomic and proteomic (i.e., molecular), histopathological imaging (i.e., cellular/tissue), and clinical (i.e., patient) data; it includes case studies for single-scale (e.g., combining genomic or histopathological image data), multiscale (e.g., combining histopathological image and clinical data), and multiscale and multiplatform (e.g., the Human Protein Atlas and The Cancer Genome Atlas) data integration. Numerous opportunities exist in biomedical informatics research focusing on integration of multiscale and multiplatform data.

Self-image and eating disorder symptoms in normal and clinical adolescents.

Science.gov (United States)

Forsén Mantilla, Emma; Bergsten, Katja; Birgegård, Andreas

2014-01-01

Eating disorders (ED) are psychiatric disorders of multifactorial origin, predominantly appearing in adolescence. Negative self-image is identified as risk factor, but the association between self-image and ED in adolescents or sex differences regarding such associations remains unclear. The study aimed to investigate the relationship between specific self-image aspects and ED symptoms in normal and clinical adolescents, including sex differences. Participants included 855 ED patients (girls=813, boys=42) and 482 normal adolescents (girls=238, boys=244), 13-15 years. Stepwise regression demonstrated strong associations between self-image and ED in normal adolescents (girls: R(2)=.31, boys: R(2)=.08), and stronger associations in patients (girls: R(2)=.64, boys: R(2)=.69). Qualitative sex differences were observed in patients. Connections between specific self-image aspects and ED have implications for clinical management of ED. The strong link between self-image variables and ED symptoms in normal girls, but not boys, is discussed in terms of the continuity-discontinuity hypothesis. Copyright © 2013 Elsevier Ltd. All rights reserved.

Intramuscular leukemic relapse: clinical signs and imaging findings. A multicentric analysis

Energy Technology Data Exchange (ETDEWEB)

Surov, Alexey [Martin Luther University Halle-Wittenberg, Department of Radiology, Halle (Germany); University of Leipzig, Department of Diagnostic and Interventional Radiology, Leipzig (Germany); Kiratli, Hayyam [Hacettepe University School of Medicine, Department of Ophthalmology, Ankara (Turkey); Im, Soo Ah [Seoul St. Mary' s Hospital, Department of Radiology, Seoul (Korea, Republic of); Manabe, Yasuhiro [National Hospital Organization Okayama Medical Center, Department of Neurology, Okayama (Japan); O' Neill, Alibhe; Shinagare, Atul B. [Brigham and Women' s Hospital, Department of Radiology, Boston, MA (United States); Spielmann, Rolf Peter [Martin Luther University Halle-Wittenberg, Department of Radiology, Halle (Germany)

2014-09-26

Leukemia is a group of malignant diseases involving peripheral blood and bone marrow. Extramedullary tumor manifestation in leukemia can also occur. They more often involve lymph nodes, skin, and bones. Intramuscular leukemic relapse (ILR) is very unusual. The aim of this analysis was to summarize the reported data regarding clinical signs and radiological features of ILR. The PubMed database was searched for publications related to ILR. After an analysis of all identified articles, 20 publications matched the inclusion criteria. The authors of the 20 publications were contacted and provided imaging of their cases for review. The following were recorded: age, gender, primary diagnosis, clinical signs, pattern, localization and size of the intramuscular leukemic relapse. Images of 16 patients were provided [8 computer tomographic (CT) images and 15 magnetic resonance images, MRI]. Furthermore, one patient with ILR was identified in our institutional database. Therefore, images of 17 patients were available for further analysis. Overall, 32 cases with ILR were included in the analysis. In most cases acute myeloid leukemia was diagnosed. Most ILRs were localized in the extremities (44 %) and in the extraocular muscles (44 %). Clinically, ILR manifested as local pain, swelling and muscle weakness. Radiologically, ILR presented most frequently with diffuse muscle infiltration. On postcontrast CT/MRI, most lesions demonstrated homogeneous enhancement. ILRs were hypo-/isointense on T1w and hyperintense on T2w images. ILR manifests commonly as focal pain, swelling and muscle weakness. ILR predominantly involved the extraocular musculature and the extremities. Radiologically, diffuse muscle infiltration was the most common imaging finding. (orig.)

Feasibility of using ‘lung density’ values estimated from EIT images for clinical diagnosis of lung abnormalities in mechanically ventilated ICU patients

International Nuclear Information System (INIS)

Nebuya, Satoru; Koike, Tomotaka; Imai, Hiroshi; Iwashita, Yoshiaki; Brown, Brian H; Soma, Kazui

2015-01-01

This paper reports on the results of a study which compares lung density values obtained from electrical impedance tomography (EIT), clinical diagnosis and CT values (HU) within a region of interest in the lung. The purpose was to assess the clinical use of lung density estimation using EIT data. In 11 patients supported by a mechanical ventilator, the consistency of regional lung density measurements as estimated by EIT was validated to assess the feasibility of its use in intensive care medicine. There were significant differences in regional lung densities recorded in the supine position between normal lungs and diseased lungs associated with pneumonia, atelectasis and pleural effusion (normal; 240 ± 71.7 kg m"−"3, pneumonia; 306 ± 38.6 kg m"−"3, atelectasis; 497 ± 130 kg m"−"3, pleural effusion; 467 ± 113 kg m"−"3: Steel–Dwass test, p < 0.05). In addition, in order to compare lung density with CT image pixels, the image resolution of CT images, which was originally 512 × 512 pixels, was changed to 16 × 16 pixels to match that of the EIT images. The results of CT and EIT images from five patients in an intensive care unit showed a correlation coefficient of 0.66 ± 0.13 between the CT values (HU) and the lung density values (kg m"−"3) obtained from EIT. These results indicate that it may be possible to obtain a quantitative value for regional lung density using EIT. (paper)

Effective choices for diagnostic imaging in clinical practice. Excerpts from a report of a WHO Scientific Group on Clinical Diagnostic Imaging

International Nuclear Information System (INIS)

1992-01-01

There are so many different methods of diagnostic imaging that medical practitioners may need guidance to choose the best through the maze of options for each clinical problem. Advice may be required for more than just the first choice, because the first imaging procedure does not always give the desired answer and, depending on the results, further imaging may have to undertaken. The alternative is to submit the patient to a barrage of imaging and hope that one type, at least provides the diagnosis. This is a quite unacceptable way to practice medicine because of the cost and the risk of radiation damage from unnecessary examinations. The choice of the most effective imaging is often difficult and frequently controversial. The sequence to be followed vries with many factors: the equipment available, the skills of the practitioner, the expected quality of the results, the quality of interpretation, and conclusion which can be drawn

NCI Workshop Report: Clinical and Computational Requirements for Correlating Imaging Phenotypes with Genomics Signatures

Directory of Open Access Journals (Sweden)

Rivka Colen

2014-10-01

Full Text Available The National Cancer Institute (NCI Cancer Imaging Program organized two related workshops on June 26–27, 2013, entitled “Correlating Imaging Phenotypes with Genomics Signatures Research” and “Scalable Computational Resources as Required for Imaging-Genomics Decision Support Systems.” The first workshop focused on clinical and scientific requirements, exploring our knowledge of phenotypic characteristics of cancer biological properties to determine whether the field is sufficiently advanced to correlate with imaging phenotypes that underpin genomics and clinical outcomes, and exploring new scientific methods to extract phenotypic features from medical images and relate them to genomics analyses. The second workshop focused on computational methods that explore informatics and computational requirements to extract phenotypic features from medical images and relate them to genomics analyses and improve the accessibility and speed of dissemination of existing NIH resources. These workshops linked clinical and scientific requirements of currently known phenotypic and genotypic cancer biology characteristics with imaging phenotypes that underpin genomics and clinical outcomes. The group generated a set of recommendations to NCI leadership and the research community that encourage and support development of the emerging radiogenomics research field to address short-and longer-term goals in cancer research.

Clinical imaging guidelines part 4: challenges in identifying, engaging and collaborating with stakeholders.

Science.gov (United States)

Bettmann, Michael A; Oikarinen, Helja; Rehani, Madan; Holmberg, Ola; del Rosario Perez, Maria; Naidoo, Anusha; Do, Kyung-Hyun; Dreyer, Keith; Ebdon-Jackson, Steve

2015-04-01

The effective development and use of clinical imaging guidelines requires an understanding of who the stakeholders are, what their interests in the process are, and what roles they should play. If the appropriate stakeholders are not engaged in the right roles, it is unlikely that clinical imaging guidelines will be successfully developed, relied on, and actually used. Some stakeholders are obvious: for the development of clinical imaging guidelines, both imagers and those who request examinations, such as general practitioners, internists, and medical specialists, must be involved. To gain acceptance, other relevant groups are stakeholders, including medical societies, other health care professionals, insurers, health IT experts and vendors, and patients. The role of stakeholders must be dictated by their specific interest. For some, involvement in the creation of guidelines is the right role. For others, such as regulators or insurers, reviews or invitations to comment are required, and for others, such as medical educators, it is probably sufficient to provide information and create awareness. Only through a careful consideration of who the stakeholders are and what are their interests are the successful development, acceptance, and use of clinical imaging guidelines likely to occur. Future efforts must focus on collaboration, particularly among groups that create clinical imaging guidelines and those that can support their use, and on regulatory roles and mandates. Copyright © 2015 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Building blocks for a clinical imaging informatics environment.

Science.gov (United States)

Kohli, Marc D; Warnock, Max; Daly, Mark; Toland, Christopher; Meenan, Chris; Nagy, Paul G

2014-04-01

Over the past 20 years, imaging informatics has been driven by the widespread adoption of radiology information and picture archiving and communication and speech recognition systems. These three clinical information systems are commonplace and are intuitive to most radiologists as they replicate familiar paper and film workflow. So what is next? There is a surge of innovation in imaging informatics around advanced workflow, search, electronic medical record aggregation, dashboarding, and analytics tools for quality measures (Nance et al., AJR Am J Roentgenol 200:1064-1070, 2013). The challenge lies in not having to rebuild the technological wheel for each of these new applications but instead attempt to share common components through open standards and modern development techniques. The next generation of applications will be built with moving parts that work together to satisfy advanced use cases without replicating databases and without requiring fragile, intense synchronization from clinical systems. The purpose of this paper is to identify building blocks that can position a practice to be able to quickly innovate when addressing clinical, educational, and research-related problems. This paper is the result of identifying common components in the construction of over two dozen clinical informatics projects developed at the University of Maryland Radiology Informatics Research Laboratory. The systems outlined are intended as a mere foundation rather than an exhaustive list of possible extensions.

Clinical Features and Patterns of Imaging in Cerebral Venous Sinus ...

African Journals Online (AJOL)

Background: Cerebral venous sinus thrombosis (CVST) is an uncommon neurological deficit. It shows a wide range of clinical manifestations that may mimic many other neurological disorders and lead to misdiagnosis. Imaging plays a key role in the diagnosis. Objective: To evaluate the clinical characteristics and patterns ...

Differences of Perceived Image Generated through the Web Site: Empirical Evidence Obtained in Spanish Destinations

Science.gov (United States)

Blazquez-Resino, Juan J.; Muro-Rodriguez, Ana I.; Perez-Jimenez, Israel R.

2016-01-01

In this paper, a study of the perceived destination image created by promotional Web Pages is expounded in an attempt to identify their differences as generators of destination image in the consumers' mind. Specifically, it seeks to analyse whether the web sites of different Spanish regions improve the image that consumers have of the destination, identifying their main dimensions and analysing its effect on satisfaction and intentions of the future behavior of potential visitors. To achieve these objectives and verify the hypotheses, a laboratory experiment was performed, where it was determined what changes are produced in the tourist's previous image after browsing the tourist webs of three different regions. Moreover, it analyses the differences in the effect of the perceived image on satisfaction and potential visitors' future behavioral intentions. The results obtained enable us to identify differences in the composition of the perceived image according to the destination, while confirming the significant effect of different perceived image dimensions regarding satisfaction. The results allow managers to gain a better understanding of the effectiveness of their sites from a consumer perspective as well as suggestions to follow in order to achieve greater efficiency in their communication actions in order to improve the motivation of visitors to go to the destination. PMID:27933027

Differences of perceived image generated through the Web site: Empirical Evidence Obtained in Spanish Destinations

Directory of Open Access Journals (Sweden)

Juan Jose Blazquez-Resino

2016-11-01

Full Text Available In this paper, a study of the perceived destination image created by promotional Web Pages is expounded in an attempt to identify their differences as generators of destination image in the consumers’ mind. Specifically, it seeks to analyse whether the web sites of different Spanish regions improve the image that consumers have of the destination, identifying their main dimensions and analysing its effect on satisfaction and intentions of the future behaviour of potential visitors. To achieve these objectives and verify the hypotheses, a laboratory experiment was performed, where it was determined what changes are produced in the tourist´s previous image after browsing the tourist webs of three different regions. Moreover, it analyses the differences in the effect of the perceived image on satisfaction and potential visitors´ future behavioural intentions. The results obtained enable us to identify differences in the composition of the perceived image according to the destination, while confirming the significant effect of different perceived image dimensions regarding satisfaction. The results allow managers to gain a better understanding of the effectiveness of their sites from a consumer perspective as well as suggestions to follow in order to achieve greater efficiency in their communication actions in order to improve the motivation of visitors to go to the destination.

[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.

[3D imaging benefits in clinical pratice of orthodontics].

Science.gov (United States)

Frèrejouand, Emmanuel

2016-12-01

3D imaging possibilities raised up in the last few years in the orthodontic field. In 2016, it can be used for diagnosis improvement and treatment planning by using digital set up combined to CBCT. It is relevant for orthodontic mechanic updating by creating visible or invisible customised appliances. It forms the basis of numerous scientific researches. The author explains the progress 3D imaging brings to diagnosis and clinics but also highlights the requirements it creates. The daily use of these processes in orthodontic clinical practices needs to be regulated regarding the benefit/risk ratio and the patient satisfaction. The command of the digital work flow created by these technics requires habits modifications from the orthodontist and his staff. © EDP Sciences, SFODF, 2016.

Anatomic Illustrations of Cranial Ultrasound Images Obtained Through the Mastoid Fontanelle in Neonates

Energy Technology Data Exchange (ETDEWEB)

Kim, Bong Man; Lee, Young Seok [Dankook University Hospital, Cheonan (Korea, Republic of)

2011-09-15

Neonatal cranial sonography performed through the mastoid fontanelle is more useful to evaluate the peripheral structures at the convexity of the cerebral hemispheres and brainstem rather than that performed through the anterior fontanelle. The purpose of this study is to demonstrate the anatomy of the extracerebral CSF space and brainstem and to suggest appropriate scan planes for performing neonatal cranial sonography through the mastoid fontanelle using MRI and multiplanar reconstruction programs. A neonate with normal features on ultrasonography and good image quality on MRI, including the 3D-SPGR axial scans, was selected. We made the reconstructed MR images corresponding to the sonongraphic planes and the anatomic models of the neonatal cranial sonographic images by using axial MRI as the standard reference on the same screen. We demonstrated the sonographic images at the levels of the body of the caudate nucleus and lentiform nucleus, the head of the caudate nucleus and thalamus, the third ventricle and midbrain, and the midbrain and cerebellar vermis on the oblique axial scans. Four oblique coronal images at the levels of the periventricular white matter, basal ganglia, thalamus and tentorium were also obtained. We illustrated the anatomic atlas with including four oblique axial scans and four oblique coronal scans that corresponded to the neonatal cranial sonographic images through the mastoid fontanelle. We objectively analyzed the anatomy of the extracerebral CSF space and brainstem by using MRI and multiplanar reconstruction programs and we provided the standardized sonographic scan planes through the mastoid fontanelle. This study will be very helpful for evaluating the abnormalities of the peripheral structures at the convexity of the cerebral hemispheres and brainstem

Imaging of Mucosal Inflammation: Current Technological Developments, Clinical Implications, and Future Perspectives

Directory of Open Access Journals (Sweden)

Maximilian J. Waldner

2017-10-01

Full Text Available In recent years, various technological developments markedly improved imaging of mucosal inflammation in patients with inflammatory bowel diseases. Although technological developments such as high-definition-, chromo-, and autofluorescence-endoscopy led to a more precise and detailed assessment of mucosal inflammation during wide-field endoscopy, probe-based and stationary confocal laser microscopy enabled in vivo real-time microscopic imaging of mucosal surfaces within the gastrointestinal tract. Through the use of fluorochromes with specificity against a defined molecular target combined with endoscopic techniques that allow ultrastructural resolution, molecular imaging enables in vivo visualization of single molecules or receptors during endoscopy. Molecular imaging has therefore greatly expanded the clinical utility and applications of modern innovative endoscopy, which include the diagnosis, surveillance, and treatment of disease as well as the prediction of the therapeutic response of individual patients. Furthermore, non-invasive imaging techniques such as computed tomography, magnetic resonance imaging, scintigraphy, and ultrasound provide helpful information as supplement to invasive endoscopic procedures. In this review, we provide an overview on the current status of advanced imaging technologies for the clinical non-invasive and endoscopic evaluation of mucosal inflammation. Furthermore, the value of novel methods such as multiphoton microscopy, optoacoustics, and optical coherence tomography and their possible future implementation into clinical diagnosis and evaluation of mucosal inflammation will be discussed.

Acceptance criteria for reprocessed AcuNav catheters: comparison between functionality testing and clinical image assessment.

Science.gov (United States)

Bank, Alan J; Berry, James M; Wilson, Robert F; Lester, Bruce R

2009-03-01

The AcuNav-catheter is a vector-phased array ultrasound catheter that has shown great utility for both diagnosis and electrophysiological interventions. To test the feasibility of limited catheter reuse and to ensure that reprocessed catheters would produce acceptable clinical images, the present study compared the 2-D and Doppler image quality, as determined by clinical assessment, with the catheter's functional status as determined by the FirstCall 2000 transducer tester. Reprocessed catheters from four functional categories, two acceptable and two unacceptable, were used to collect images, 2-D and Doppler, from a porcine heart. The images were blinded and then rated by clinical evaluation. The study found that catheter images from all functional categories were found to be clinically acceptable except for those from the lowest unacceptable category. In addition, examination of tip deflection characteristics showed no significant difference between new and reprocessed catheters. We conclude that reprocessed AcuNav catheters that pass functional tests are able to produce clinical images, 2-D and Doppler, which are equivalent to their new counterparts.

NMR imaging of the head-neck region. Topography of function - clinical findings - imaging and spectroscopy

International Nuclear Information System (INIS)

Vogl, T.J.

1991-01-01

The book on nmr imaging in the head-neck region offers, on a total of 221 pages, 344 detailed representations with 141 figures and 44 tables. It provides information as to the relevant topography of function, presents clinical findings, explains imaging characteristics and also takes account of spectroscopic procedures. The multifarious methods of investigation are described and discussed in connection with the differential diagnoses. A score of suitable diagnostic measures is assigned to each region of examination. The method's value is assessed against that of other imaging techniques. (orig.) [de

Imaging: Guiding the Clinical Translation of Cardiac Stem Cell Therapy

Science.gov (United States)

Nguyen, Patricia K.; Lan, Feng; Wang, Yongming; Wu, Joseph C.

2011-01-01

Stem cells have been touted as the holy grail of medical therapy with promises to regenerate cardiac tissue, but it appears the jury is still out on this novel therapy. Using advanced imaging technology, scientists have discovered that these cells do not survive nor engraft long-term. In addition, only marginal benefit has been observed in large animal studies and human trials. However, all is not lost. Further application of advanced imaging technology will help scientists unravel the mysteries of stem cell therapy and address the clinical hurdles facing its routine implementation. In this review, we will discuss how advanced imaging technology will help investigators better define the optimal delivery method, improve survival and engraftment, and evaluate efficacy and safety. Insights gained from this review may direct the development of future preclinical investigations and clinical trials. PMID:21960727

Initial clinical experiences with dopamine D2 receptor imaging by means of 2'-iodospiperone and single-photon emission computed tomography

International Nuclear Information System (INIS)

Yonekura, Yoshiharu; Saji, Hideo; Iwasaki, Yasushi

1995-01-01

Dopamine D 2 receptor imaging was performed with 123 I labeled 2'-iodospiperone (2'-ISP) and single-photon emission computed tomography (SPECT) in 9 patients: 4 with idiopathic Parkinson's disease, 2 with parkinsonism, 1 with Wilson's disease and 2 with pituitary tumor, and the results were compared with the data for 9 normal subjects. Following an intravenous injection of 123 I-2'-ISP, early (within 30 min) and late (between 2 and 4 hr) SPECT images were obtained by means of a multi-detector SPECT scanner or a rotating gamma camera. In normal subjects, early SPECT images demonstrated uniform distribution of radioactivity in the cerebral gray matter and cerebellum reflecting regional cerebral blood flow, whereas late SPECT images showed high radioactivity only in the basal ganglia. All the patients with Parkinson's disease also demonstrated symmetrical basal ganglia uptake in the late SPECT images, but it was diminished in parkinsonism and Wilson's disease. One patient with a growth hormone-producing pituitary tumor had a positive uptake in the tumor. These preliminary clinical data demonstrated that 2'-ISP can be used for SPECT imaging of D 2 dopamine receptors and may be of clinical value for the diagnosis and planning of the treatment of neurological diseases. (author)

Recent advances in computational methods and clinical applications for spine imaging

CERN Document Server

Glocker, Ben; Klinder, Tobias; Li, Shuo

2015-01-01

This book contains the full papers presented at the MICCAI 2014 workshop on Computational Methods and Clinical Applications for Spine Imaging. The workshop brought together scientists and clinicians in the field of computational spine imaging. The chapters included in this book present and discuss the new advances and challenges in these fields, using several methods and techniques in order to address more efficiently different and timely applications involving signal and image acquisition, image processing and analysis, image segmentation, image registration and fusion, computer simulation, image based modeling, simulation and surgical planning, image guided robot assisted surgical and image based diagnosis. The book also includes papers and reports from the first challenge on vertebra segmentation held at the workshop.

Image De-Identification Methods for Clinical Research in the XDS Environment

NARCIS (Netherlands)

Aryanto, K. Y. E.; van Kernebeek, G.; Berendsen, B.; Oudkerk, M.; van Ooijen, P. M. A.

To investigate possible de-identification methodologies within the Cross-Enterprise Document Sharing for imaging (XDS-I) environment in order to provide strengthened support for image data exchange as part of clinical research projects. De-identification, using anonymization or pseudonymization, is

Multimodal imaging of bone metastases: From preclinical to clinical applications

Directory of Open Access Journals (Sweden)

Stephan Ellmann

2015-10-01

Full Text Available Metastases to the skeletal system are commonly observed in cancer patients, highly affecting the patients' quality of life. Imaging plays a major role in detection, follow-up, and molecular characterisation of metastatic disease. Thus, imaging techniques have been optimised and combined in a multimodal and multiparametric manner for assessment of complementary aspects in osseous metastases. This review summarises both application of the most relevant imaging techniques for bone metastasis in preclinical models and the clinical setting.

[Clinical, pathological and imaging features of primary pelvic Ewing's sarcoma].

Science.gov (United States)

Liu, J; Chen, Y; Ling, X L; Gong, Y; Ding, J P; Zhang, Z K; Wang, Y J

2016-07-19

To explore the clinical, pathological and imaging features of Ewing's sarcoma in pelvis and to improve knowledge and diagnosis of the disease. A retrospective analysis of the clinical, pathological and imaging data of pathologically confirmed 13 cases of Ewing's sarcoma in pelvis was carried out between May 2008 and March 2016 in the Affiliated Hospital of Hangzhou Normal University, the Third Hospital of Hebei Medical University and the Second Hospital of Hebei Medical University. The median age 13 cases of pelvic primary Ewing's sarcoma was 17 years old.The X-ray and CT imagings showed osteolytic and mixed bone destruction, CT showed mixed type in 10 cases, 8 cases of bone tumors as a flocculent, 10 cases of bone expansion failure, 10 cases of periosteal reaction, the layered 5 cases, radial in 5 cases.Thirteen cases showed soft tissue mass, soft tissue mass was equal or slightly lower density.Four cases showed heterogeneous contrast enhancement.The lesions showed low signal in T1WI and mixed high signal in T2WI of magnetic resonance imaging(MRI). The boundary of the lesions were obscure, and 5 cases had patchy necrosis area, and 9 cases had incomplete false capsule, surrounding soft tissue was violated.Four cases showed heterogeneous contrast enhancement after MRI enhancement scan. The age of onset of Ewing's sarcoma of the pelvis is more concentrated in about 15 years.The imaging feaures are mixed bone destruction and more bone is swelling and permeability damage, soft tissue mass is larger, bone tumor is cloudy or acicular, periosteal reaction in a layered and radial, most cases show that the false envelope is not complete.Combined with clinical and imaging examination, the diagnosis of the disease can be made.

Quality image and incident air kerma evaluation in X-ray chest exams

International Nuclear Information System (INIS)

Campos de O, P. M.; Do Carmo S, P.; De Sousa L, M. A.; Da Silva, T. A.

2017-10-01

The procedures optimization for obtaining diagnostic quality images is an important factor to the patients radiation levels submitted to diagnostic radiology examinations was the lowest as reasonably practicable. Two methodologies for image quality parameters evaluation were applied in the routine of three diagnostic radiology clinics (A, B and C), two with digital image processing and one with chemical processing in Belo Horizonte, Brazil. The incident air kerma was evaluated for the radiographic techniques used in the clinic routine chest exams, approved in accordance with European Image Quality Criteria. It was possible to determine that the Fluke Biomedical X-ray Phantom test objects coupled to the Leeds Test Objects (TOR CDR) obtained better results than Gammex s Radiographic Survey Phantom (RSV), because the low and high contrast structures present in the RSV were not visualized in lower energies. The three clinics presented very similar results in all image quality parameters in the evaluation with the TOR CDR test object. However, clinic C presented an low contrast structures result 28.1 % lower than clinical B, although the average Ka,i to obtain their images was 33.4 % superior. The clinic A results present the best relation between image quality and radiation dose in patients. It was verified the optimization doses possibility in diagnostic radiology services with digital processing system, without significant reduction in image quality. Patients submitted to the highest radiation levels belonged to the clinic that presented the worst results in the image quality parameters evaluated. (Author)

Pre-clinical functional magnetic resonance imaging. Pt. I. The kidney

Energy Technology Data Exchange (ETDEWEB)

Zoellner, Frank G.; Kalayciyan, Raffi; Chacon-Caldera, Jorge; Zimmer, Fabian; Schad, Lothar R. [Heidelberg Univ., Mannheim (Germany). Computer Assisted Clinical Medicine

2014-07-01

The prevalence of chronic kidney disease (CKD) is increasing worldwide. In Europe alone, at least 8% of the population currently has some degree of CKD. CKD is associated with serious comorbidity, reduced life expectancy, and high economic costs; hence, the early detection and adequate treatment of kidney disease is important. Pre-clinical research can not only give insights into the mechanisms of the various kidney diseases but it also allows for investigating the outcome of new drugs developed to treat kidney disease. Functional magnetic resonance imaging provides non-invasive access to tissue and organ function in animal models. Advantages over classical animal research approaches are numerous: the same animal might be repeatedly imaged to investigate a progress or a treatment of disease over time. This has also a direct impact on animal welfare and the refinement of classical animal experiments as the number of animals in the studies might be reduced. In this paper, we review current state of the art in functional magnetic resonance imaging with a focus on pre-clinical kidney imaging.

Pre-clinical functional magnetic resonance imaging. Pt. I. The kidney

International Nuclear Information System (INIS)

Zoellner, Frank G.; Kalayciyan, Raffi; Chacon-Caldera, Jorge; Zimmer, Fabian; Schad, Lothar R.

2014-01-01

The prevalence of chronic kidney disease (CKD) is increasing worldwide. In Europe alone, at least 8% of the population currently has some degree of CKD. CKD is associated with serious comorbidity, reduced life expectancy, and high economic costs; hence, the early detection and adequate treatment of kidney disease is important. Pre-clinical research can not only give insights into the mechanisms of the various kidney diseases but it also allows for investigating the outcome of new drugs developed to treat kidney disease. Functional magnetic resonance imaging provides non-invasive access to tissue and organ function in animal models. Advantages over classical animal research approaches are numerous: the same animal might be repeatedly imaged to investigate a progress or a treatment of disease over time. This has also a direct impact on animal welfare and the refinement of classical animal experiments as the number of animals in the studies might be reduced. In this paper, we review current state of the art in functional magnetic resonance imaging with a focus on pre-clinical kidney imaging.

CT and MR imaging of the liver. Clinical importance of nutritional status

International Nuclear Information System (INIS)

Leander, P.; Sjoeberg, S.; Hoeglund, P.

2000-01-01

Purpose: In an experimental study in rats a correlation between nutritional status and hepatic attenuation in CT and signal intensities in MR imaging was shown. Is physiological nutritional status of importance in clinical CT and MR imaging? Material and methods: In a cross-over study including 12 healthy volunteers (6 women and 6 men, mean age 34 years), CT and MR imaging of the liver were performed with nutritional status at three different levels, i.e., normal, fasting and after glycogen-rich meals. CT and MR were performed on clinical imaging systems and hepatic attenuation and signal intensity, respectively, were assessed. In MR, T1-weighted, proton density-weighted and T2-weighted pulse-sequences were used. Results: In CT there were significantly (p<0.01) higher liver attenuations in normal nutritional status and after glycogen rich-meals compared to the fasting condition. The difference between fasting and glycogen-rich meals were 10.5 HU for men, 7.4 for women and mean 8.8 HU for all 12 volunteers. In MR imaging the differences were small and non-significant. The results of this study are in accordance with an earlier experimental study in rats. Conclusion: In CT it may be of importance not to have patients in a fasting condition as it lowers the attenuation in normal liver tissue. The findings are important for planning of clinical studies where hepatic attenuation will be assessed and may be of some importance in clinical CT. In MR imaging the results indicate that the nutritional status is of less importance

Quantitative comparison of OSEM and penalized likelihood image reconstruction using relative difference penalties for clinical PET

International Nuclear Information System (INIS)

Ahn, Sangtae; Asma, Evren; Cheng, Lishui; Manjeshwar, Ravindra M; Ross, Steven G; Miao, Jun; Jin, Xiao; Wollenweber, Scott D

2015-01-01

Ordered subset expectation maximization (OSEM) is the most widely used algorithm for clinical PET image reconstruction. OSEM is usually stopped early and post-filtered to control image noise and does not necessarily achieve optimal quantitation accuracy. As an alternative to OSEM, we have recently implemented a penalized likelihood (PL) image reconstruction algorithm for clinical PET using the relative difference penalty with the aim of improving quantitation accuracy without compromising visual image quality. Preliminary clinical studies have demonstrated visual image quality including lesion conspicuity in images reconstructed by the PL algorithm is better than or at least as good as that in OSEM images. In this paper we evaluate lesion quantitation accuracy of the PL algorithm with the relative difference penalty compared to OSEM by using various data sets including phantom data acquired with an anthropomorphic torso phantom, an extended oval phantom and the NEMA image quality phantom; clinical data; and hybrid clinical data generated by adding simulated lesion data to clinical data. We focus on mean standardized uptake values and compare them for PL and OSEM using both time-of-flight (TOF) and non-TOF data. The results demonstrate improvements of PL in lesion quantitation accuracy compared to OSEM with a particular improvement in cold background regions such as lungs. (paper)

Multimodality molecular imaging - from target description to clinical studies

International Nuclear Information System (INIS)

Schober, O.; Rahbar, K.; Riemann, B.

2009-01-01

This highlight lecture was presented at the closing session of the Annual Congress of the European Association of Nuclear Medicine (EANM) in Munich on 15 October 2008. The Congress was a great success: there were more than 4,000 participants, and 1,597 abstracts were submitted. Of these, 1,387 were accepted for oral or poster presentation, with a rejection rate of 14%. In this article a choice was made from 100 of the 500 lectures which received the highest scores by the scientific review panel. This article outlines the major findings and trends at the EANM 2008, and is only a brief summary of the large number of outstanding abstracts presented. Among the great number of oral and poster presentations covering nearly all fields of nuclear medicine some headlines have to be defined highlighting the development of nuclear medicine in the 21st century. This review focuses on the increasing impact of molecular and multimodality imaging in the field of nuclear medicine. In addition, the question may be asked as to whether the whole spectrum of nuclear medicine is nothing other than molecular imaging and therapy. Furthermore, molecular imaging will and has to go ahead to multimodality imaging. In view of this background the review was structured according to the single steps of molecular imaging, i.e. from target description to clinical studies. The following topics are addressed: targets, radiochemistry and radiopharmacy, devices and computer science, animals and preclinical evaluations, and patients and clinical evaluations. (orig.)

A review of methods of clinical image quality evaluation in mammography

International Nuclear Information System (INIS)

Li Yanpeng; Poulos, Ann; McLean, Donald; Rickard, Mary

2010-01-01

Purpose: Consistency in evaluation of mammography images in research and clinical practice is dependent on a standardised clinical image quality evaluation system. Currently two such systems are available-one developed by the American College of Radiology (ACR) and the other by the European Commission (EU guidelines). The purpose of this study was to review mammography clinical evaluation methods in research studies and their adherence to these systems. Method: A total of 23 research articles were reviewed from the period 2000-2006, 11 of these studies used digital images. The focus of the review was the criteria and rating scales used. Results: Only 5 studies used either the ACR (3) or EU guidelines (2). The remainder included aspects of these systems together with a range of other criteria and rating scales. Variation was found in the categories of criteria used, number of criteria, the descriptors of the criteria and the instructions used to evaluate the criteria. Instructions were frequently not specific and open to individual interpretation. Although breast density is an important criterion of image quality and contributes to perception of breast lesions, inclusion of this criterion was not universal, and even when used the area of breast density to be evaluated was not identified, thus enhancing inter-observer variability. Scales that were absolute or relative were used for evaluation, all of which incorporated inconsistent numbers of steps. Conclusion: Low adherence to ACR and EU Guidelines has resulted in considerable variation in the evaluation methods used in research studies. The implications of this variability are considerable both for evaluation of image quality in research outcomes and clinical practice.

Object detection from images obtained through underwater turbulence medium

Science.gov (United States)

Furhad, Md. Hasan; Tahtali, Murat; Lambert, Andrew

2017-09-01

Imaging through underwater experiences severe distortions due to random fluctuations of temperature and salinity in water, which produces underwater turbulence through diffraction limited blur. Lights reflecting from objects perturb and attenuate contrast, making the recognition of objects of interest difficult. Thus, the information available for detecting underwater objects of interest becomes a challenging task as they have inherent confusion among the background, foreground and other image properties. In this paper, a saliency-based approach is proposed to detect the objects acquired through an underwater turbulent medium. This approach has drawn attention among a wide range of computer vision applications, such as image retrieval, artificial intelligence, neuro-imaging and object detection. The image is first processed through a deblurring filter. Next, a saliency technique is used on the image for object detection. In this step, a saliency map that highlights the target regions is generated and then a graph-based model is proposed to extract these target regions for object detection.

Level-set-based reconstruction algorithm for EIT lung images: first clinical results.

Science.gov (United States)

Rahmati, Peyman; Soleimani, Manuchehr; Pulletz, Sven; Frerichs, Inéz; Adler, Andy

2012-05-01

We show the first clinical results using the level-set-based reconstruction algorithm for electrical impedance tomography (EIT) data. The level-set-based reconstruction method (LSRM) allows the reconstruction of non-smooth interfaces between image regions, which are typically smoothed by traditional voxel-based reconstruction methods (VBRMs). We develop a time difference formulation of the LSRM for 2D images. The proposed reconstruction method is applied to reconstruct clinical EIT data of a slow flow inflation pressure-volume manoeuvre in lung-healthy and adult lung-injury patients. Images from the LSRM and the VBRM are compared. The results show comparable reconstructed images, but with an improved ability to reconstruct sharp conductivity changes in the distribution of lung ventilation using the LSRM.

Level-set-based reconstruction algorithm for EIT lung images: first clinical results

International Nuclear Information System (INIS)

Rahmati, Peyman; Adler, Andy; Soleimani, Manuchehr; Pulletz, Sven; Frerichs, Inéz

2012-01-01

We show the first clinical results using the level-set-based reconstruction algorithm for electrical impedance tomography (EIT) data. The level-set-based reconstruction method (LSRM) allows the reconstruction of non-smooth interfaces between image regions, which are typically smoothed by traditional voxel-based reconstruction methods (VBRMs). We develop a time difference formulation of the LSRM for 2D images. The proposed reconstruction method is applied to reconstruct clinical EIT data of a slow flow inflation pressure–volume manoeuvre in lung-healthy and adult lung-injury patients. Images from the LSRM and the VBRM are compared. The results show comparable reconstructed images, but with an improved ability to reconstruct sharp conductivity changes in the distribution of lung ventilation using the LSRM. (paper)

Clinical and Imaging Findings in Childhood Posterior Reversible Encephalopathy Syndrome

Science.gov (United States)

GUNGOR, Serdal; KILIC, Betul; TABEL, Yilmaz; SELIMOGLU, Ayse; OZGEN, Unsal; YILMAZ, Sezai

2018-01-01

Objective Posterior reversible encephalopathy syndrome (PRES) is characterized by typical radiologic findings in the posterior regions of the cerebral hemispheres and cerebellum. The symptoms include headache, nausea, vomiting, visual disturbances, focal neurologic deficits, and seizures. The aim of this study is to evaluate the clinical and radiological features of PRES in children and to emphasize the recognition of atypical features. Materials & Methods We retrospectively examined 23 children with PRES from Mar 2010-Apr 2015 in Inonu University Turgut Ozal Medical Center in Turkey. We compared the clinical features and cranial MRI findings between underlying diseases of PRES. Results The most common precipitating factors were hypertension (78.2%) and medications, namely immunosuppressive and antineoplastic agents (60.8%). Manifestations included mental changes (100%), seizures (95.6%), headache (60.8%), and visual disturbances (21.7%) of mean 3.6 (range 1-10) days' duration. Cranial magnetic resonance imaging (MRI) showed bilateral occipital lesions in all patients, associated in 82.6% with less typical distribution of lesions in frontal, temporal or parietal lobes, cerebellum, corpus callosum, basal ganglia, thalamus, and brain stem. Frontal involvement was predominant, observed in 56.5% of patients. Clinical recovery was followed by radiologic resolution in all patients. Conclusion PRES is often unsuspected by the clinician, thus radiologists may be the first to suggest this diagnosis on an MRI obtained for seizures or encephalopathy. Atypical MRI finding is seen quite often. Rapid diagnosis and treatment are required to avoid a devastating outcome. PMID:29379559

Lateral epicondylitis and beyond: imaging of lateral elbow pain with clinical-radiologic correlation

International Nuclear Information System (INIS)

Kotnis, Nikhil A.; Chiavaras, Mary M.; Harish, Srinivasan

2012-01-01

The diagnosis of lateral epicondylitis is often straightforward and can be made on the basis of clinical findings. However, radiological assessment is valuable where the clinical picture is less clear or where symptoms are refractory to treatment. Demographics, aspects of clinical history, or certain physical signs may suggest an alternate diagnosis. Knowledge of the typical clinical presentation and imaging findings of lateral epicondylitis, in addition to other potential causes of lateral elbow pain, is necessary. These include entrapment of the posterior interosseous and lateral antebrachial cutaneous nerves, posterolateral rotatory instability, posterolateral plica syndrome, Panner's disease, osteochondritis dissecans of the capitellum, radiocapitellar overload syndrome, occult fractures and chondral-osseous impaction injuries, and radiocapitellar arthritis. Knowledge of these potential masquerades of lateral epicondylitis and their characteristic clinical and imaging features is essential for accurate diagnosis. The goal of this review is to provide an approach to the imaging of lateral elbow pain, discussing the relevant anatomy, various causes, and discriminating factors, which will allow for an accurate diagnosis. (orig.)

High-speed imaging at 3 tesla. A technical and clinical review with an emphasis on whole-brain 3D imaging

International Nuclear Information System (INIS)

Naganawa, Shinji; Kawai, Hisashi; Fukatsu, Hiroshi; Ishigaki, Takeo; Komada, Tomomi

2005-01-01

Improvements to the inherently high specific-absorption rate (SAR) of high-speed imaging at 3T are necessary in order to render this method clinically feasible. Various efforts have been undertaken to improve the associated hardware and software. In this review, we focus on whole-brain isotropic 3D imaging with a turbo spin-echo sequence with variable flip-angle echo trains (3D-TSE-VFL) and present its technical and clinical features. This sequence can be used to acquire images of various contrasts including T 2 -weighted, fat-suppressed T 2 -weighted, fluid-attenuated inversion recovery (FLAIR), fat-suppressed FLAIR, and STIR (short tau inversion recovery). Various aspects of 3D-TSE-VFL are discussed, including CSF (cerebrospinal fluid) and metal artifacts, STIR contrast, small-part visualization other than brain, and the possibility of serial subtraction. Some images from clinical cases are presented. (author)

Clinical significance of dynamic magnetic resonance imaging in the evaluation of wrist joint in Rheumatoid arthritis

International Nuclear Information System (INIS)

Shim, Yong Woon; Suh, Jin Suck; Lee, Soo Kon; Lee, Ji Soo; Cho, Jae Hyun

1996-01-01

To assess the role of contrast-enhanced dynamic Magnetic Resonance Imaging in evaluation disease activity of rheumatoid arthritis. Forty-seven wrist joints with rheumatoid arthritis were examined prospectively. Coronal images of the wrist were obtained using fat-suppression Fast multi-planar spoiled gradient recalled (FMPSPGR) acquisition in the steady state ; TR/TE 102/6.4 msec, flip angle = 60, 4 slices per sequence, FOV = 8 cm, matrix 256 X 192 at 1.5 Tesla. Scans were carried out once before and five to eight times after an intravenous Gd-DPTA injection, at 30-second-intervals. The enhancement of synovium were measured, the enhancement ratio was calculated(postcontrast SNR/precontrast SNR) and time-enhancement ratio curves were plotted. Patients were divided into three groups according to the ratio of initial to peak enhancement : less than 30% ; 30-80% more than 80%. Differences among the three groups were statistically tested using clinical indices and laboratory data as variable. Comparing one group with another, there were no significant differences in clinical indices and laboratory data except for the parameter of grip strength. Enhancement pattern measured in a single wrist joint was not comparable to a clinical index in predicting disease activity in rheumatoid arthritis

Obtaining TEM images with a uniform deviation parameter

International Nuclear Information System (INIS)

Eades, Alwyn

2006-01-01

In transmission electron microscopes made during the last quarter of a century, it has been impossible to take images in which the diffraction contrast conditions are uniform across the field of view. This is inconvenient when, for example, imaging dislocations at a relatively low magnification. The problem arises because modern microscopes use immersion lenses in which the sample sits in a high magnetic field. The resulting helical trajectories of the electrons at the sample plane mean that it is not possible to make a beam that is parallel at the sample. Results of a method to overcome this problem are presented. It is shown that a simple modification to the microscope (which, on a computer-controlled microscope, could be implemented in software) can be used to produce images in which the deviation parameter is essentially constant across many microns of image. By a happy accident, this method can be used, not only to correct for the helicity imparted by immersion lenses, but also to correct for buckling of the sample (up to a point)

Diffusion weighted imaging demystified. The technique and potential clinical applications for soft tissue imaging

International Nuclear Information System (INIS)

Ahlawat, Shivani; Fayad, Laura M.

2018-01-01

Diffusion-weighted imaging (DWI) is a fast, non-contrast technique that is readily available and easy to integrate into an existing imaging protocol. DWI with apparent diffusion coefficient (ADC) mapping offers a quantitative metric for soft tissue evaluation and provides information regarding the cellularity of a region of interest. There are several available methods of performing DWI, and artifacts and pitfalls must be considered when interpreting DWI studies. This review article will review the various techniques of DWI acquisition and utility of qualitative as well as quantitative methods of image interpretation, with emphasis on optimal methods for ADC measurement. The current clinical applications for DWI are primarily related to oncologic evaluation: For the assessment of de novo soft tissue masses, ADC mapping can serve as a useful adjunct technique to routine anatomic sequences for lesion characterization as cyst or solid and, if solid, benign or malignant. For treated soft tissue masses, the role of DWI/ADC mapping in the assessment of treatment response as well as recurrent or residual neoplasm in the setting of operative management is discussed, especially when intravenous contrast medium cannot be given. Emerging DWI applications for non-neoplastic clinical indications are also reviewed. (orig.)

Diffusion weighted imaging demystified. The technique and potential clinical applications for soft tissue imaging

Energy Technology Data Exchange (ETDEWEB)

Ahlawat, Shivani [The Johns Hopkins Medical Institutions, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Fayad, Laura M. [The Johns Hopkins Medical Institutions, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); The Johns Hopkins Medical Institutions, Department of Oncology, Baltimore, MD (United States); The Johns Hopkins Medical Institutions, Department of Orthopaedic Surgery, Baltimore, MD (United States)

2018-03-15

Diffusion-weighted imaging (DWI) is a fast, non-contrast technique that is readily available and easy to integrate into an existing imaging protocol. DWI with apparent diffusion coefficient (ADC) mapping offers a quantitative metric for soft tissue evaluation and provides information regarding the cellularity of a region of interest. There are several available methods of performing DWI, and artifacts and pitfalls must be considered when interpreting DWI studies. This review article will review the various techniques of DWI acquisition and utility of qualitative as well as quantitative methods of image interpretation, with emphasis on optimal methods for ADC measurement. The current clinical applications for DWI are primarily related to oncologic evaluation: For the assessment of de novo soft tissue masses, ADC mapping can serve as a useful adjunct technique to routine anatomic sequences for lesion characterization as cyst or solid and, if solid, benign or malignant. For treated soft tissue masses, the role of DWI/ADC mapping in the assessment of treatment response as well as recurrent or residual neoplasm in the setting of operative management is discussed, especially when intravenous contrast medium cannot be given. Emerging DWI applications for non-neoplastic clinical indications are also reviewed. (orig.)

Quantitative Clinical Imaging Methods for Monitoring Intratumoral Evolution.

Science.gov (United States)

Kim, Joo Yeun; Gatenby, Robert A

2017-01-01

Solid tumors are multiscale, open, complex, dynamic systems: complex because they have many interacting components, dynamic because both the components and their interactions can change with time, and open because the tumor freely communicates with surrounding and even distant host tissue. Thus, it is not surprising that striking intratumoral variations are commonly observed in clinical imaging such as MRI and CT and that several recent studies found striking regional variations in the molecular properties of cancer cells from the same tumor. Interestingly, this spatial heterogeneity in molecular properties of tumor cells is typically ascribed to branching clonal evolution due to accumulating mutations while macroscopic variations observed in, for example, clinical MRI scans are usually viewed as functions of blood flow. The clinical significance of spatial heterogeneity has not been fully determined but there is a general consensus that the varying intratumoral landscape along with patient factors such as age, morbidity and lifestyle, contributes significantly to the often unpredictable response of individual patients within a disease cohort treated with the same standard-of-care therapy.Here we investigate the potential link between macroscopic tumor heterogeneity observed by clinical imaging and spatial variations in the observed molecular properties of cancer cells. We build on techniques developed in landscape ecology to link regional variations in the distribution of species with local environmental conditions that define their habitat. That is, we view each region of the tumor as a local ecosystem consisting of environmental conditions such as access to nutrients, oxygen, and means of waste clearance related to blood flow and the local population of tumor cells that both adapt to these conditions and, to some extent, change them through, for example, production of angiogenic factors. Furthermore, interactions among neighboring habitats can produce broader

Dry Kit Development And Clinical Test Of 99mTc-L,L-ECD Radiopharmaceutical For Vrain Perfusion Imaging

International Nuclear Information System (INIS)

Kartini, Nani; Sofyan, Rohestri; Rukmini; Iswahyudi

2000-01-01

Technetium- 99m ethyl cysteinate dimer ( 99m Tc-L,L-ECD) has been synthesized and formulated based on ligand exchanged reaction with 99mTc-glucoheptonate. Considering the low stability of the dry kit produced, it was fairly necessary to develop the manufacture of L,L-ECD dry kit in order to obtain a more stable one that meet the requirements as brain perfusion imaging radiopharmaceutical. Experiment was done by modifying the packing of dry kit components of the previous formulation. Characteristics of 99m Tc-L,L-ECD produced from this formulation were studied by carrying out the sterility and toxicity test, then followed with clinical test to some volunteers. Evaluation of brain perfusion was done by tomography technique using gamma camera at Nuclear Medicine Installation, Hasan Sadikin Hospital. The modified formulation obtained consist of three components i.e. main ligand L,L-ECD; exchange ligand Ca-glucoheptonate and HaOH. Its stability could reach 8 months at-10 derajat C of storage. Effects of toxicity on mice did not appear. The result of clinical study shows that the radiopharmaceutical was distributed very rapidly in the blood brain circulations and retained in the brain for about one hour. The body scanning indicates that the substance was excreted in the brain for about one hour. The body scanning indicates that the substance was excreted though kidney, liver and spleen. Based on the results obtained the radiopharmaceutical could be promoted to be used for brain perfusion imaging

Clinical and imaging assessment of cognitive dysfunction in multiple sclerosis

DEFF Research Database (Denmark)

Rocca, Maria A; Amato, Maria P; De Stefano, Nicola

2015-01-01

In patients with multiple sclerosis (MS), grey matter damage is widespread and might underlie many of the clinical symptoms, especially cognitive impairment. This relation between grey matter damage and cognitive impairment has been lent support by findings from clinical and MRI studies. However...... that causes clinical symptoms to trigger. Findings on cortical reorganisation support the contribution of brain plasticity and cognitive reserve in limiting cognitive deficits. The development of clinical and imaging biomarkers that can monitor disease development and treatment response is crucial to allow...

Functional imaging in oncology. Clinical applications. Vol. 2

Energy Technology Data Exchange (ETDEWEB)

Luna, Antonio [Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Radiology; MRI Health Time Group, Jaen (Spain); Vilanova, Joan C. [Girona Univ. (Spain). Clinica Girona - Hospital Sta. Caterina; Hygino da Cruz, L. Celso Jr. (ed.) [CDPI and IRM, Rio de Janeiro (Brazil). Dept. of Radiology; Rossi, Santiago E. [Centro de Diagnostico, Buenos Aires (Argentina)

2014-06-01

Easy-to-read manual on new functional imaging techniques in oncology. Explains current clinical applications and outlines future avenues. Includes numerous high-quality illustrations to highlight the major teaching points. In the new era of functional and molecular imaging, both currently available imaging biomarkers and biomarkers under development are expected to lead to major changes in the management of oncological patients. This two-volume book is a practical manual on the various imaging techniques capable of delivering functional information on cancer, including diffusion MRI, perfusion CT and MRI, dual-energy CT, spectroscopy, dynamic contrast-enhanced ultrasonography, PET, and hybrid modalities. This second volume considers the applications and benefits of these techniques in a wide range of tumor types, including their role in diagnosis, prediction of treatment outcome, and early evaluation of treatment response. Each chapter addresses a specific malignancy and is written by one or more acclaimed experts. The lucid text is complemented by numerous high-quality illustrations that highlight key features and major teaching points.

Functional imaging in oncology. Clinical applications. Vol. 2

International Nuclear Information System (INIS)

Luna, Antonio; Vilanova, Joan C.

2014-01-01

Easy-to-read manual on new functional imaging techniques in oncology. Explains current clinical applications and outlines future avenues. Includes numerous high-quality illustrations to highlight the major teaching points. In the new era of functional and molecular imaging, both currently available imaging biomarkers and biomarkers under development are expected to lead to major changes in the management of oncological patients. This two-volume book is a practical manual on the various imaging techniques capable of delivering functional information on cancer, including diffusion MRI, perfusion CT and MRI, dual-energy CT, spectroscopy, dynamic contrast-enhanced ultrasonography, PET, and hybrid modalities. This second volume considers the applications and benefits of these techniques in a wide range of tumor types, including their role in diagnosis, prediction of treatment outcome, and early evaluation of treatment response. Each chapter addresses a specific malignancy and is written by one or more acclaimed experts. The lucid text is complemented by numerous high-quality illustrations that highlight key features and major teaching points.

Clinical evaluation of 2D versus 3D whole-body PET image quality using a dedicated BGO PET scanner

International Nuclear Information System (INIS)

Visvikis, D.; Griffiths, D.; Costa, D.C.; Bomanji, J.; Ell, P.J.

2005-01-01

Three-dimensional positron emission tomography (3D PET) results in higher system sensitivity, with an associated increase in the detection of scatter and random coincidences. The objective of this work was to compare, from a clinical perspective, 3D and two-dimensional (2D) acquisitions in terms of whole-body (WB) PET image quality with a dedicated BGO PET system. 2D and 3D WB emission acquisitions were carried out in 70 patients. Variable acquisition parameters in terms of time of emission acquisition per axial field of view (aFOV) and slice overlap between sequential aFOVs were used during the 3D acquisitions. 3D and 2D images were reconstructed using FORE+WLS and OSEM respectively. Scatter correction was performed by convolution subtraction and a model-based scatter correction in 2D and 3D respectively. All WB images were attenuation corrected using segmented transmission scans. Images were blindly assessed by three observers for the presence of artefacts, confidence in lesion detection and overall image quality using a scoring system. Statistically significant differences between 2D and 3D image quality were only obtained for 3D emission acquisitions of 3 min. No statistically significant differences were observed for image artefacts or lesion detectability scores. Image quality correlated significantly with patient weight for both modes of operation. Finally, no differences were seen in image artefact scores for the different axial slice overlaps considered, suggesting the use of five slice overlaps in 3D WB acquisitions. 3D WB imaging using a dedicated BGO-based PET scanner offers similar image quality to that obtained in 2D considering similar overall times of acquisitions. (orig.)

Integration of Medical Imaging Including Ultrasound into a New Clinical Anatomy Curriculum

Science.gov (United States)

Moscova, Michelle; Bryce, Deborah A.; Sindhusake, Doungkamol; Young, Noel

2015-01-01

In 2008 a new clinical anatomy curriculum with integrated medical imaging component was introduced into the University of Sydney Medical Program. Medical imaging used for teaching the new curriculum included normal radiography, MRI, CT scans, and ultrasound imaging. These techniques were incorporated into teaching over the first two years of the…

The Clinical Role of 99mTc-(V)-DMSA Imaging in Patients with Head and Neck Cancer

International Nuclear Information System (INIS)

Bae, Sun Kun; Lee, Jae Tae; Park, June Sik

1995-01-01

99m Tc-(V)-DMSA is a tumor seeking agent that has been used to image medullary carcinoma of thyroid, soft tissue sarcoma and lung cancer. This study was designed to assess the clinical role of DMSA in the diagnosis of head and neck cancers. We has evaluated the diagnostic efficacy of planar and SPECT imaging using 99m Tc-(V)-DMSA. Sixty-eight patients with head and neck mass were included in this study. All subjects were diagnosed by biopsy or surgery. Planar and SPECT images were obtained at 2 or 3 hour after intravenous injection of 740 MBq(20 mCi) 99m Tc-(V)-DMSA. Seventeen patients also underwent SPECT imaging using dual head camera. The diagnostic sensitivity of 99m Tc-(V)-DMSA planar and SPECT imaging was 65% and 90%, and specificity was 80% and 66%, respectively. The sensitivity of planar imaging in squamous cell carcinoma was similar to overall sensitivity. Six metastatic lesion were first diagnosed by scintigraphy. But benign lesions such as Kikuchi syndrome, tuberculous lymphadenitis also revealed increased uptake. 99m Tc-(V)-DMSA imaging seems to be a promising method in the evaluation of patients with head and neck mass. We recommend SPECT imaging to delineate anatomic localization of the lesion.

Imaging system for obtaining space- and time-resolved plasma images on TMX

International Nuclear Information System (INIS)

Koehler, H.A.; Frerking, C.E.

1980-01-01

A Reticon 50 x 50 photodiode array camera has been placed on Livermore's Tandem Mirror Experiment to view a 56-cm diameter plasma source of visible, vacuum-ultraviolet, and x-ray photons. The compact camera views the source through a pinhole, filters, a fiber optic coupler, a microchannel plate intensifier (MCPI), and a reducer. The images are digitized (at 3.3 MHz) and stored in a large, high-speed memory that has a capacity of 45 images. A local LSI-11 microprocessor provides immediate processing and display of the data. The data are also stored on floppy disks that can be further processed on the large Livermore Computer System. The temporal resolution is limited by the fastest MCPI gate. The number of images recorded is determined by the read-out time of the Reticon camera (minimum 0.9 msec). The spatial resolution of approximately 1.4 cm is fixed by the geometry and the pinhole of 0.025 cm. Typical high-quality color representation of some plasma images are included

Nuclear Medicine imaging of infection and inflammation Part 3: Clinical applications

International Nuclear Information System (INIS)

Gnanasegaran, G.; Croasdale, J.; Buscombe, J.R.

2005-01-01

Prompt localization of infection sites is essential for initiating appropriate therapeutic measures. There have been major advances in the management of patients suffering from infective and/or inflammatory disorders as a result of introduction of newer drugs with high sensitivity and specificity. However diagnosis of infection / inflammation still remains a major clinical problem. Although the typical signs of infection and inflammation are useful in localizing the pathology at superficial sites, infection and inflammation of internal structures are often difficult to localize without the aid of imaging procedures. Radionuclide imaging is an important diagnostic tool for the evaluation of patho-physiological processes of infection and inflammation. A spectrum of radiopharmaceuticals and a number of imaging protocols have been used in clinical practice. However every method differs in its potential to gather information at the cellular and molecular level. This review addresses some of the applications of radionuclide infection imaging procedures in musculoskeletal system, lymphatic system, in immunocompromised patients and in patients suffering from fever of unknown origin. (author)

Development and clinical implementation of an enhanced display algorithm for use in networked electronic portal imaging

International Nuclear Information System (INIS)

Heuvel, Frank van den; Han, Ihn; Chungbin, Suzanne; Strowbridge, Amy; Tekyi-Mensah, Sam; Ragan, Don P.

1999-01-01

Purpose: To introduce and clinically validate a preprocessing algorithm that allows clinical images from an electronic portal imaging device (EPID) to be displayed on any computer monitor, without loss of clinical usability. The introduction of such a system frees EPI systems from the constraints of fixed viewing workstations and increases mobility of the images in a department. Methods and Materials: The preprocessing algorithm, together with its variable parameters is introduced. Clinically, the algorithm is tested using an observer study of 316 EPID images of the pelvic region in the framework of treatment of carcinoma of the cervix and endometrium. Both anterior-posterior (AP/PA) and latero-lateral (LAT) images were used. The images scored were taken from six different patients, five of whom were obese, female, and postmenopausal. The result is tentatively compared with results from other groups. The scoring system, based on the number of visible landmarks in the port, is proposed and validated. Validation was performed by having the observer panel score images with artificially induced noise levels. A comparative study was undertaken with a standard automatic window and leveling display technique. Finally, some case studies using different image sites and EPI detectors are presented. Results: The image quality for all images in this study was deemed to be clinically useful (mean score > 1). Most of the images received a score which was second highest (AP/PA landmarks ≥ 6 and LAT landmarks ≥ 5). Obesity, which has been an important factor determining the image quality, was not seen to be a factor here. Compared to standard techniques a highly significant improvement was determined with regard to clinical usefulness. The algorithm performs fast (less than 9 seconds) and needs no additional user interaction in most of the cases. The algorithm works well on both direct detection portal imagers and camera-based imagers whether analog or digital cameras

PET in tumor imaging: research only or a cost effective clinical tool?

International Nuclear Information System (INIS)

Wahl, R.L.

1997-01-01

PET imaging has for many years been a versatile tool for non-invasive imaging of neuro-physiology and, indeed, whole body physiology. Quantitative PET imaging of trace amounts of radioactivity is scientifically elegant and can be very complex. This lecture focuses on whether and where this test is clinically useful. Because of the research tradition, PET imaging has been perceived as an 'expensive' test, as it costs more per scan than CT and MRI scans at most institutions. Such a superficial analysis is incorrect, however, as it is increasingly recognized that imaging costs, which in some circumstances will be increased by the use of PET, are only a relatively small component of patient care costs. Thus, PET may raise imaging costs and the number of imaging procedures in some settings, though PET may reduce imaging test numbers in other settings. However, the analysis must focus on the total costs of patient management. Analyses focused on total patient care costs, including cost of hospitalization and cost surgery as well as imaging costs, have shown that PET can substantially reduce total patient care costs in several settings. This is achieved by providing a more accurate diagnosis, and thus having fewer instances of an incorrect diagnosis resulting in subsequent inappropriate surgery or investigations. Several institutions have shown scenarios in which PET for tumor imaging is cost effective. While the specific results of the analyses vary based on disease prevalence and cost input values for each procedure, as well as the projected performance of PET, the similar results showing total care cost savings in the management of several common cancers, strongly supports the rational for the use of PET in cancer management. In addition, promising clinical results are forthcoming in several other illnesses, suggesting PET will have broader utility than these uses, alone. Thus, while PET is an 'expensive' imaging procedure and has considerable utility as a research

Clinical comparison between 100 mm photofluorography and digital (1024/sup 2/) fluoroscopic image acquisition

International Nuclear Information System (INIS)

Hynes, D.M.; Edmonds, E.W.; Rowlands, J.A.; Porter, A.J.; Toth, B.D.

1986-01-01

The authors describe current work in progress in which a clinical image can be recorded on both 100-mm film and a 1,024/sup 2/ image store with the same exposure. The 100-mm film is exposed in the usual manner. However, the same radiation exposure is utilized by the optics of the beam splitter to transfer the output image of the intensifier into a 1,024/sup 2/ image store and thence to hard copy by multiformat camera or laser printer. Comparative phantom and clinical images will be presented, along with observations on dose rates needed for diagnostic digital imaging. Use of this system may allow fluoroscopic dose rates to be reduced

Initial clinical experiences with dopamine D{sub 2} receptor imaging by means of 2`-iodospiperone and single-photon emission computed tomography

Energy Technology Data Exchange (ETDEWEB)

Yonekura, Yoshiharu [Fukui Medical Schoool, Matsuoka (Japan). Biomedical Imaging Research Center; Saji, Hideo; Iwasaki, Yasushi [and others

1995-08-01

Dopamine D{sub 2} receptor imaging was performed with {sup 123}I labeled 2`-iodospiperone (2`-ISP) and single-photon emission computed tomography (SPECT) in 9 patients: 4 with idiopathic Parkinson`s disease, 2 with parkinsonism, 1 with Wilson`s disease and 2 with pituitary tumor, and the results were compared with the data for 9 normal subjects. Following an intravenous injection of {sup 123}I-2`-ISP, early (within 30 min) and late (between 2 and 4 hr) SPECT images were obtained by means of a multi-detector SPECT scanner or a rotating gamma camera. In normal subjects, early SPECT images demonstrated uniform distribution of radioactivity in the cerebral gray matter and cerebellum reflecting regional cerebral blood flow, whereas late SPECT images showed high radioactivity only in the basal ganglia. All the patients with Parkinson`s disease also demonstrated symmetrical basal ganglia uptake in the late SPECT images, but it was diminished in parkinsonism and Wilson`s disease. One patient with a growth hormone-producing pituitary tumor had a positive uptake in the tumor. These preliminary clinical data demonstrated that 2`-ISP can be used for SPECT imaging of D{sub 2} dopamine receptors and may be of clinical value for the diagnosis and planning of the treatment of neurological diseases. (author).

WE-DE-207A-00: Advances in Image-Guided Neurointerventions-Clinical Pull and Technology Push

Energy Technology Data Exchange (ETDEWEB)

NONE

2016-06-15

1. Parallels in the evolution of x-ray angiographic systems and devices used for minimally invasive endovascular therapy Charles Strother - DSA, invented by Dr. Charles Mistretta at UW-Madison, was the technology which enabled the development of minimally invasive endovascular procedures. As DSA became widely available and the potential benefits for accessing the cerebral vasculature from an endovascular approach began to be apparent, industry began efforts to develop tools for use in these procedures. Along with development of catheters, embolic materials, pushable coils and the GDC coils there was simultaneous development and improvement of 2D DSA image quality and the introduction of 3D DSA. Together, these advances resulted in an enormous expansion in the scope and numbers of minimally invasive endovascular procedures. The introduction of flat detectors for c-arm angiographic systems in 2002 provided the possibility of the angiographic suite becoming not just a location for vascular imaging where physiological assessments might also be performed. Over the last decade algorithmic and hardware advances have been sufficient to now realize this potential in clinical practice. The selection of patients for endovascular treatments is enhanced by this dual capability. Along with these advances has been a steady reduction in the radiation exposure required so that today, vascular and soft tissue images may be obtained with equal or in many cases less radiation exposure than is the case for comparable images obtained with multi-detector CT. Learning Objectives: To understand the full capabilities of today’s angiographic suite To understand how c-arm cone beam CT soft tissue imaging can be used for assessments of devices, blood flow and perfusion. Advances in real-time x-ray neuro-endovascular image guidance Stephen Rudin - Reacting to the demands on real-time image guidance for ever finer neurovascular interventions, great improvements in imaging chains are being

WE-DE-207A-00: Advances in Image-Guided Neurointerventions-Clinical Pull and Technology Push

International Nuclear Information System (INIS)

2016-01-01

1. Parallels in the evolution of x-ray angiographic systems and devices used for minimally invasive endovascular therapy Charles Strother - DSA, invented by Dr. Charles Mistretta at UW-Madison, was the technology which enabled the development of minimally invasive endovascular procedures. As DSA became widely available and the potential benefits for accessing the cerebral vasculature from an endovascular approach began to be apparent, industry began efforts to develop tools for use in these procedures. Along with development of catheters, embolic materials, pushable coils and the GDC coils there was simultaneous development and improvement of 2D DSA image quality and the introduction of 3D DSA. Together, these advances resulted in an enormous expansion in the scope and numbers of minimally invasive endovascular procedures. The introduction of flat detectors for c-arm angiographic systems in 2002 provided the possibility of the angiographic suite becoming not just a location for vascular imaging where physiological assessments might also be performed. Over the last decade algorithmic and hardware advances have been sufficient to now realize this potential in clinical practice. The selection of patients for endovascular treatments is enhanced by this dual capability. Along with these advances has been a steady reduction in the radiation exposure required so that today, vascular and soft tissue images may be obtained with equal or in many cases less radiation exposure than is the case for comparable images obtained with multi-detector CT. Learning Objectives: To understand the full capabilities of today’s angiographic suite To understand how c-arm cone beam CT soft tissue imaging can be used for assessments of devices, blood flow and perfusion. Advances in real-time x-ray neuro-endovascular image guidance Stephen Rudin - Reacting to the demands on real-time image guidance for ever finer neurovascular interventions, great improvements in imaging chains are being

Evaluation of a cloud-based local-read paradigm for imaging evaluations in oncology clinical trials for lung cancer

International Nuclear Information System (INIS)

Sueoka-Aragane, Naoko; Kobayashi, Naomi; Bonnard, Eric; Charbonnier, Colette; Yamamichi, Junta; Mizobe, Hideaki; Kimura, Shinya

2015-01-01

Although tumor response evaluated with radiological imaging is frequently used as a primary endpoint in clinical trials, it is difficult to obtain precise results because of inter- and intra-observer differences. To evaluate usefulness of a cloud-based local-read paradigm implementing software solutions that standardize imaging evaluations among international investigator sites for clinical trials of lung cancer. Two studies were performed: KUMO I and KUMO I Extension. KUMO I was a pilot study aiming at demonstrating the feasibility of cloud implementation and identifying issues regarding variability of evaluations among sites. Chest CT scans at three time-points from baseline to progression, from 10 patients with lung cancer who were treated with EGFR tyrosine kinase inhibitors, were evaluated independently by two oncologists (Japan) and one radiologist (France), through a cloud-based software solution. The KUMO I Extension was performed based on the results of KUMO I. KUMO I showed discordance rates of 40% for target lesion selection, 70% for overall response at the first time-point, and 60% for overall response at the second time-point. Since the main reason for the discordance was differences in the selection of target lesions, KUMO I Extension added a cloud-based quality control service to achieve a consensus on the selection of target lesions, resulting in an improved rate of agreement of response evaluations. The study shows the feasibility of imaging evaluations at investigator sites, based on cloud services for clinical studies involving multiple international sites. This system offers a step forward in standardizing evaluations of images among widely dispersed sites

Adaptive digital image processing in real time: First clinical experiences

International Nuclear Information System (INIS)

Andre, M.P.; Baily, N.A.; Hier, R.G.; Edwards, D.K.; Tainer, L.B.; Sartoris, D.J.

1986-01-01

The promise of computer image processing has generally not been realized in radiology, partly because the methods advanced to date have been expensive, time-consuming, or inconvenient for clinical use. The authors describe a low-cost system which performs complex image processing operations on-line at video rates. The method uses a combination of unsharp mask subtraction (for low-frequency suppression) and statistical differencing (which adjusts the gain at each point of the image on the basis of its variation from a local mean). The operator interactively adjusts aperture size, contrast gain, background subtraction, and spatial noise reduction. The system is being evaluated for on-line fluoroscopic enhancement, for which phantom measurements and clinical results, including lithotripsy, are presented. When used with a video camera, postprocessing of radiographs was advantageous in a variety of studies, including neonatal chest studies. Real-time speed allows use of the system in the reading room as a ''variable view box.''

Malignant round cell tumours of bone: atypical clinical and imaging features

International Nuclear Information System (INIS)

Saifuddin, A.; Whelan, J.; Pringle, J.A.S.; Cannon, S.R.

2000-01-01

Objective. To describe the clinical, radiological and MRI features of six atypical cases of histologically proven appendicular Ewing sarcoma/ primitive neuroectodermal tumour (PNET). Design. Retrospective review of case notes and available imaging was carried out. Patients. Six patients (4 male, 2 female; mean age 27 years, range 19-44 years), presenting over a 77-month period, were identified from the Bone Tumour Register. All had unusual clinical and imaging features for Ewing sarcoma/PNET.Results and conclusions. Four tumours were centred on the distal femoral metaphysis, one in the proximal tibial metaphysis and one in the distal tibial metaphysis. Plain radiographs were available in four cases and showed minor cortical changes. MRI demonstrated a relatively small, eccentrically located intraosseous component with a large, eccentric extraosseous component. Extension into the epiphysis was seen in three cases and into the adjacent joint in two cases. Intraosseous ''skip'' metastases were present in three cases. The clinical and imaging features were atypical for conventional intraosseous Ewing sarcoma/PNET and the exact site of origin (intraosseous, periosteal or soft-tissue) was unclear. (orig.)

Congenital Simple Hamartoma of Retinal Pigment Epithelium: Clinical and Imaging Findings

Directory of Open Access Journals (Sweden)

Mehmet Yasin Teke

2012-01-01

Full Text Available Congenital simple hamartoma of retinal pigment epithelium (CSHRPE is a rare, asymptomatic, and incidentally detected benign lesion. However, it is very important to do the differential diagnosis from other pigmented retinal lesions. Its clinical presentation and imaging findings are very helpful in doing this differentiation. This paper presents clinical and imaging findings of a 56-year-old woman with incidentally detected CSHRPE. The lesion was small, heavily pigmented, well circumscribed, and slightly elevated. Optical coherence tomography (OCT scanning was diagnostic and showed an elevated retina at the site of the lesion, increased optical reflectivity on its inner surface, optical shadowing of deeper structures, and clearly cut tumor margins. Ocular ultrasonography, fluorescein angiography, and fundus autofluorescence imaging which is firstly described in this report did not show any characteristic finding.

Magnetic resonance imaging of injuries to the ankle joint: can it predict clinical outcome?

Science.gov (United States)

Zanetti, M; De Simoni, C; Wetz, H H; Zollinger, H; Hodler, J

1997-02-01

To predict clinical outcome after ankle sprains on the basis of magnetic resonance (MR) findings. Twenty-nine consecutive patients (mean age 32.9 years, range 13-60 years) were examined clinically and with MR imaging both after trauma and following standardized conservative therapy. Various MR abnormalities were related to a clinical outcome score. There was a tendency for a better clinical outcome in partial, rather than complete, tears of the anterior talofibular ligament and when there was no fluid within the peroneal tendon sheath at the initial MR examination (P = 0.092 for either abnormality). A number of other MR features did not significantly influence clinical outcome, including the presence of a calcaneofibular ligament lesion and a bone bruise of the talar dome. Clinical outcome after ankle sprain cannot consistently be predicted by MR imaging, although MR imaging may be more accurate when the anterior talofibular ligament is only partially torn and there are no signs of injury to the peroneal tendon sheath.

Magnetic resonance imaging and clinical features of glenoid labral flap tears

Energy Technology Data Exchange (ETDEWEB)

Stewart, Jessica K.; Vinson, Emily N. [Duke University Hospital, Department of Radiology, Durham, NC (United States); Taylor, Dean C. [Duke University Hospital, Department of Orthopaedic Surgery, Durham, NC (United States)

2017-08-15

Displaced flaps of glenoid labral tissue are an uncommonly encountered finding on MRI of the shoulder, and are of unclear clinical significance. The purpose of this study is to describe the imaging characteristics of displaced glenoid labral flaps, evaluate for any common concomitant injuries, and identify the typical clinical presentation and management of patients with this lesion. This retrospective, observational study was approved by the institutional review board. Nineteen patients with flap-type tears of the labrum on preoperative MRI were identified. Each examination was retrospectively reviewed by two radiologists for size, location, and signal intensity of the displaced flap of tissue, in addition to any co-existing labrum or cartilage pathological conditions and clinical information. All displaced flaps extended from the inferior margin of the glenoid into the axillary recess. The average size of the visualized flap was 10.9 by 6.0 by 2.6 mm. Seventy percent of the flaps had signal intensity isointense to labrum and hypointense to hyaline cartilage on T2-weighted images. All 19 patients had concomitant labral pathological conditions and 63% had cartilage defects, visualized on MRI. Clinical evidence of shoulder instability was seen in 83% of patients, and 67% were managed surgically. Glenoid labral flap tears have distinct imaging characteristics that may aid in their identification. Their presence should prompt careful evaluation of the glenoid articular cartilage. Recognition of a labral flap tear may have clinical importance, as 83% of patients with this finding demonstrated clinical evidence of shoulder instability, often requiring surgical intervention. (orig.)

Magnetic resonance imaging and clinical features of glenoid labral flap tears

International Nuclear Information System (INIS)

Stewart, Jessica K.; Vinson, Emily N.; Taylor, Dean C.

2017-01-01

Displaced flaps of glenoid labral tissue are an uncommonly encountered finding on MRI of the shoulder, and are of unclear clinical significance. The purpose of this study is to describe the imaging characteristics of displaced glenoid labral flaps, evaluate for any common concomitant injuries, and identify the typical clinical presentation and management of patients with this lesion. This retrospective, observational study was approved by the institutional review board. Nineteen patients with flap-type tears of the labrum on preoperative MRI were identified. Each examination was retrospectively reviewed by two radiologists for size, location, and signal intensity of the displaced flap of tissue, in addition to any co-existing labrum or cartilage pathological conditions and clinical information. All displaced flaps extended from the inferior margin of the glenoid into the axillary recess. The average size of the visualized flap was 10.9 by 6.0 by 2.6 mm. Seventy percent of the flaps had signal intensity isointense to labrum and hypointense to hyaline cartilage on T2-weighted images. All 19 patients had concomitant labral pathological conditions and 63% had cartilage defects, visualized on MRI. Clinical evidence of shoulder instability was seen in 83% of patients, and 67% were managed surgically. Glenoid labral flap tears have distinct imaging characteristics that may aid in their identification. Their presence should prompt careful evaluation of the glenoid articular cartilage. Recognition of a labral flap tear may have clinical importance, as 83% of patients with this finding demonstrated clinical evidence of shoulder instability, often requiring surgical intervention. (orig.)

Clinical findings and diagnostic imaging of small intestinal rupture due to blunt abdominal trauma

International Nuclear Information System (INIS)

Takahashi, Hitoshi; Sakata, Ikuhiro; Ogawa, Masaaki; Izumoto, Gentaro; Kim, Akio; Maeda, Shigenari; Yasutomi, Masayuki; Yamamoto, Toshio

1987-01-01

Eight patients with small intestinal rupture due to blunt abdominal trauma were analyzed by their clinical findings and diagnostic imaging (plain film, ultrasound and computed tomography). Computed tomography was most useful for identification of intraabdominal extraluminal free air (pneumoperitoneum) and this finding was obtained in seven out of the eight patients (87.5 %). Intraabdominal fluid collection was observed in All the patients and was most clearly detectable by ultrasound and computed tomography. These examinations may be applied to identification of properties of the fluid collection. All the patients eventually developed peritonitis when laparotomy was decided. Thus, close follow up observation of abdominal physical signs was also of critical importance. (author)

Image registration in the brain: a test of clinical accuracy

International Nuclear Information System (INIS)

Rosenman, Julian; Miller, Elizabeth P.; Rinker, Lillian; Mukherji, Suresh; Tracton, Gregg; Cullip, Tim J.; Muller, Keith E.; DeLuca, Marla C.; Major, Stacey A.; Sailer, Scott; Varia, Mahesh

1997-01-01

Purpose/Objective: Accurate localization of tumor and normal structures is a critical step in the radiation treatment planning processes and has direct implications for tumor control success as well as normal tissue morbidity. We conducted a study to determine the accuracy of transferring tumor information from diagnostic images to the simulation films and planning CT with conventional methods using the best clinical judgment and compared that to tumor localization using 3D registration software. Materials and Methods: We measured the accuracy with which experienced clinicians could localize tumor volume from diagnostic images to either simulation films or a planning CT, with and without 3D registration software. To obtain absolute registration truth we used the method of identical pairs wherein a CT data set was duplicated and one copy resliced along a different plane than the original while maintaining the exact mathematical transformation between them. A tumor was then added to the resliced CT which became the surrogate diagnostic image. Because we were concerned that a CT/CT pair might be too easy to register, a simulated MR made by re-colorizing the resliced CT (to become a facsimile MR or fMR) was also used as a surrogate diagnostic image. Finally we studied the registration accuracy when a CT/(real)MR pair was used. The registration in this case could not be guaranteed to be exact, but the studies were obtained under carefully controlled conditions and were registered from bony landmarks using commercial radiosurgery software. A team of experts then placed the tumor from the resliced CT, fMR, or real MR to an AP and lateral 'isocenter simulation film' (a digitally reconstructed radiograph made from the unmarked CT) and to the 'planning CT' - also the unmarked CT. A registration of the data sets (CT/CT, CT/fMR and CT/MR) was also done using our 3D registration software. A total of thirty-six tasks on four subjects were performed. Four analyses (each with

Container-Based Clinical Solutions for Portable and Reproducible Image Analysis.

Science.gov (United States)

Matelsky, Jordan; Kiar, Gregory; Johnson, Erik; Rivera, Corban; Toma, Michael; Gray-Roncal, William

2018-05-08

Medical imaging analysis depends on the reproducibility of complex computation. Linux containers enable the abstraction, installation, and configuration of environments so that software can be both distributed in self-contained images and used repeatably by tool consumers. While several initiatives in neuroimaging have adopted approaches for creating and sharing more reliable scientific methods and findings, Linux containers are not yet mainstream in clinical settings. We explore related technologies and their efficacy in this setting, highlight important shortcomings, demonstrate a simple use-case, and endorse the use of Linux containers for medical image analysis.

The Role of Clinical Cardiac Magnetic Resonance Imaging in China: Current Status and the Future

Directory of Open Access Journals (Sweden)

Shi Chen, MD

2016-12-01

Full Text Available Cardiac magnetic resonance (CMR imaging plays an important role in the diagnosis and management of cardiovascular diseases. The state-of-the-art CMR imaging has many advantages in cardiac imaging, including excellent spatial and temporal resolution, unrestricted imaging field, no exposure to ionizing radiation, excellent tissue contrast, and unique myocardial tissue characterization. Clinical CMR imaging is used during the cardiovascular diagnostic workup in the United States and some European countries. Use of CMR imaging is emerging in hospitals in China and has a promising future. This review briefly describes the real-world clinical application of CMR imaging in China and discuss obstacles for its future development.

Disc pathology after whiplash injury. A prospective magnetic resonance imaging and clinical investigation.

Science.gov (United States)

Pettersson, K; Hildingsson, C; Toolanen, G; Fagerlund, M; Björnebrink, J

1997-02-01

This study was used to evaluate the relationship between magnetic resonance imaging findings and clinical findings after whiplash injury. To identify initial soft-tissue damage after whiplash injury, the development of disc pathology, and the relationship of disc pathology to clinical findings. Although a few studies have reported pathological magnetic resonance imaging findings after whiplash injuries, there is no prospective study published to our knowledge. Thirty-nine patients, 20 women and 19 men with a mean age of 32 years, were treated for whiplash injury. Magnetic resonance imaging and clinical examination were performed in a blinded manner at a mean of 11 days after trauma. The procedure was repeated at a 2-year follow-up visit. Two patients could not be examined with the second magnetic resonance imaging because of claustrophobia and pregnancy, respectively. The authors found 13 patients (33%) with disc herniations with medullary (six cases) or dura (seven cases) impingement over the 2-year follow-up period. At the follow-up examination all patients with medullary impingement had persistent or increased symptoms, and three of 27 patients (11%) with no or slight changes on magnetic resonance imaging had persistent symptoms. No ligament injuries were diagnosed. Although disc pathology seems to be one contributing factor in the development of chronic symptoms after whiplash injury, it may be unnecessary to examine these patients in the acute phase with magnetic resonance imaging; correlating initial symptoms and signs to magnetic resonance imaging findings is difficult because of the relatively high proportion of false-positive results. Magnetic resonance imaging is indicated later in the course of treatment in patients with persistent arm pain, neurologic deficits or clinical signs of nerve root compression to diagnose disc herniations requiring surgery.

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.

An evaluation of the regional cerebral blood flow (rCBF) measurement by xenon-enhanced dynamic CT with helical scanning technique and the functional imaging by multiplanar reconstruction (MPR). Fundamental study and clinical application

International Nuclear Information System (INIS)

Watanabe, Kenichi

1997-01-01

We evaluated the quantitative rCBF by xenon-enhanced dynamic CT with helical scanning technique on all brain regions, and also examined clinical usefulness of coronal and sagittal section images which are similar to SPECT images obtained by the functional multiplanar reconstitution (MPR) imaging of many successive flow maps. We used 14 clinical cases. The conventional xenon-enhanced CT was simple and ideal method to measure rCBF, however, it had disadvantages; it gives a few laminagraphical images or only the axial directional images, compared to SPECT or PET. There is a risk to overlook lesions out of the image or not to obtain the whole images of the lesion. Although the helical scanning technique has a methodological characteristics to use adjacent data for the image reconstitution, it is by no means inferior to the conventional method in the contrast resolution or the image resolution when the co-helical function and an appropriate reconstituted function were used. It has an advantage to scan all brain regions by only one cycle of scanning. Furthermore on making good use of the property that the helical scanning technique can give the successive data, we can observe rCBF by coronal and sagittal images when many flow maps were made up by reconstituted images of the narrow steps. This shows the clinical usefulness of this technique. One of the future problem to be solved is to decrease the exposure dose. (K.H.)

Lateral epicondylitis and beyond: imaging of lateral elbow pain with clinical-radiologic correlation

Energy Technology Data Exchange (ETDEWEB)

Kotnis, Nikhil A. [McMaster University, Departments of Radiology, Hamilton, ON (Canada); Sheffield Teaching Hospitals, Department of Medical Physics and Medical Imaging, Sheffield (United Kingdom); Chiavaras, Mary M. [McMaster University, Departments of Radiology, Hamilton, ON (Canada); Harish, Srinivasan [McMaster University, Departments of Radiology, Hamilton, ON (Canada); St. Joseph' s Healthcare, Department of Diagnostic Imaging, Hamilton, ON (Canada)

2012-04-15

The diagnosis of lateral epicondylitis is often straightforward and can be made on the basis of clinical findings. However, radiological assessment is valuable where the clinical picture is less clear or where symptoms are refractory to treatment. Demographics, aspects of clinical history, or certain physical signs may suggest an alternate diagnosis. Knowledge of the typical clinical presentation and imaging findings of lateral epicondylitis, in addition to other potential causes of lateral elbow pain, is necessary. These include entrapment of the posterior interosseous and lateral antebrachial cutaneous nerves, posterolateral rotatory instability, posterolateral plica syndrome, Panner's disease, osteochondritis dissecans of the capitellum, radiocapitellar overload syndrome, occult fractures and chondral-osseous impaction injuries, and radiocapitellar arthritis. Knowledge of these potential masquerades of lateral epicondylitis and their characteristic clinical and imaging features is essential for accurate diagnosis. The goal of this review is to provide an approach to the imaging of lateral elbow pain, discussing the relevant anatomy, various causes, and discriminating factors, which will allow for an accurate diagnosis. (orig.)

Clinical features and 123I-FP-CIT SPECT imaging in drug-induced parkinsonism and Parkinson's disease

International Nuclear Information System (INIS)

Diaz-Corrales, Francisco J.; Escobar-Delgado, Teresa; Sanz-Viedma, Salome; Garcia-Solis, David; Mir, Pablo

2010-01-01

To determine clinical predictors and accuracy of 123 I-FP-CIT SPECT imaging in the differentiation of drug-induced parkinsonism (DIP) and Parkinson's disease (PD). Several clinical features and 123 I-FP-CIT SPECT images in 32 patients with DIP, 25 patients with PD unmasked by antidopaminergic drugs (PDu) and 22 patients with PD without a previous history of antidopaminergic treatment (PDc) were retrospectively evaluated. DIP and PD shared all clinical features except symmetry of parkinsonian signs which was more frequently observed in patients with DIP (46.9%) than in patients with PDu (16.0%, p 123 I-FP-CIT SPECT images were normal in 29 patients with DIP (90.6%) and abnormal in all patients with PD, and this imaging technique showed high levels of accuracy. DIP and PD are difficult to differentiate based on clinical signs. The precision of clinical diagnosis could be reliably enhanced by 123 I-FP-CIT SPECT imaging. (orig.)

Ulnar-sided wrist pain. II. Clinical imaging and treatment

Energy Technology Data Exchange (ETDEWEB)

Watanabe, Atsuya; Souza, Felipe [Brigham and Women' s Hospital, Department of Radiology, Boston, MA (United States); Vezeridis, Peter S.; Blazar, Philip [Brigham and Women' s Hospital, Department of Orthopaedic Surgery, Boston, MA (United States); Yoshioka, Hiroshi [Brigham and Women' s Hospital, Department of Radiology, Boston, MA (United States); University of California-Irvine, Department of Radiological Sciences, Irvine, CA (United States); UC Irvine Medical Center, Department of Radiological Sciences, Orange, CA (United States)

2010-09-15

Pain at the ulnar aspect of the wrist is a diagnostic challenge for hand surgeons and radiologists due to the small and complex anatomical structures involved. In this article, imaging modalities including radiography, arthrography, ultrasound (US), computed tomography (CT), CT arthrography, magnetic resonance (MR) imaging, and MR arthrography are compared with regard to differential diagnosis. Clinical imaging findings are reviewed for a more comprehensive understanding of this disorder. Treatments for the common diseases that cause the ulnar-sided wrist pain including extensor carpi ulnaris (ECU) tendonitis, flexor carpi ulnaris (FCU) tendonitis, pisotriquetral arthritis, triangular fibrocartilage complex (TFCC) lesions, ulnar impaction, lunotriquetral (LT) instability, and distal radioulnar joint (DRUJ) instability are reviewed. (orig.)

Multi-layer imager design for mega-voltage spectral imaging

Science.gov (United States)

Myronakis, Marios; Hu, Yue-Houng; Fueglistaller, Rony; Wang, Adam; Baturin, Paul; Huber, Pascal; Morf, Daniel; Star-Lack, Josh; Berbeco, Ross

2018-05-01

The architecture of multi-layer imagers (MLIs) can be exploited to provide megavoltage spectral imaging (MVSPI) for specific imaging tasks. In the current work, we investigated bone suppression and gold fiducial contrast enhancement as two clinical tasks which could be improved with spectral imaging. A method based on analytical calculations that enables rapid investigation of MLI component materials and thicknesses was developed and validated against Monte Carlo computations. The figure of merit for task-specific imaging performance was the contrast-to-noise ratio (CNR) of the gold fiducial when the CNR of bone was equal to zero after a weighted subtraction of the signals obtained from each MLI layer. Results demonstrated a sharp increase in the CNR of gold when the build-up component or scintillation materials and thicknesses were modified. The potential for low-cost, prompt implementation of specific modifications (e.g. composition of the build-up component) could accelerate clinical translation of MVSPI.

Multimodality imaging techniques.

Science.gov (United States)

Martí-Bonmatí, Luis; Sopena, Ramón; Bartumeus, Paula; Sopena, Pablo

2010-01-01

In multimodality imaging, the need to combine morphofunctional information can be approached by either acquiring images at different times (asynchronous), and fused them through digital image manipulation techniques or simultaneously acquiring images (synchronous) and merging them automatically. The asynchronous post-processing solution presents various constraints, mainly conditioned by the different positioning of the patient in the two scans acquired at different times in separated machines. The best solution to achieve consistency in time and space is obtained by the synchronous image acquisition. There are many multimodal technologies in molecular imaging. In this review we will focus on those multimodality image techniques more commonly used in the field of diagnostic imaging (SPECT-CT, PET-CT) and new developments (as PET-MR). The technological innovations and development of new tracers and smart probes are the main key points that will condition multimodality image and diagnostic imaging professionals' future. Although SPECT-CT and PET-CT are standard in most clinical scenarios, MR imaging has some advantages, providing excellent soft-tissue contrast and multidimensional functional, structural and morphological information. The next frontier is to develop efficient detectors and electronics systems capable of detecting two modality signals at the same time. Not only PET-MR but also MR-US or optic-PET will be introduced in clinical scenarios. Even more, MR diffusion-weighted, pharmacokinetic imaging, spectroscopy or functional BOLD imaging will merge with PET tracers to further increase molecular imaging as a relevant medical discipline. Multimodality imaging techniques will play a leading role in relevant clinical applications. The development of new diagnostic imaging research areas, mainly in the field of oncology, cardiology and neuropsychiatry, will impact the way medicine is performed today. Both clinical and experimental multimodality studies, in

Hypoxic-Ischemic Encephalopathy With Clinical and Imaging Abnormalities Limited to Occipital Lobe.

Science.gov (United States)

Parmar, Hemant A; Trobe, Jonathan D

2016-09-01

The vulnerable brain areas in hypoxic-ischemic encephalopathy (HIE) following systemic hypotension are typically the neocortex, deep cerebral gray nuclei, hippocampus, cerebellum, and the parieto-occipital arterial border zone region. The visual cortex is not commonly recognized as a target in this setting. Single-institution review from 2007 to 2015 of patients who suffered cortical visual loss as an isolated clinical manifestation following systemic hypotension and whose brain imaging showed abnormalities limited to the occipital lobe. Nine patients met inclusion criteria. Visual loss at outset ranged from hand movements to 20/20, but all patients had homonymous field loss at best. In 1 patient, imaging was initially normal but 4 months later showed encephalomalacia. In 2 patients, imaging was initially subtle enough to be recognized as abnormal only when radiologists were advised that cortical visual loss was present. The occipital lobe may be an isolated target in HIE with cortical visual loss as the only clinical manifestation. Imaging performed in the acute period may appear normal or disclose abnormalities subtle enough to be overlooked. Radiologists informed of the clinical manifestations may be more attune to these abnormalities, which will become more apparent months later when occipital volume loss develops.

Image artifacts from MR-based attenuation correction in clinical, whole-body PET/MRI

DEFF Research Database (Denmark)

Keller, Sune H; Holm, Søren; Hansen, Adam E

2013-01-01

Integrated whole-body PET/MRI tomographs have become available. PET/MR imaging has the potential to supplement, or even replace combined PET/CT imaging in selected clinical indications. However, this is true only if methodological pitfalls and image artifacts arising from novel MR-based attenuation...

Metanephric Adenoma: clinical, imaging, and histological findings

Energy Technology Data Exchange (ETDEWEB)

Torricelli, Fabio Cesar Miranda; Marchini, Giovanni Scala, E-mail: fabio_torri@yahoo.com.b [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Medicina. Dept. de Urologica; Campos, Rodrigo Sousa Madeira [Hospital do Servidor Publico Estadual, Sao Paulo, SP (Brazil). Dept. de Urologia; Gil, Antonio Otero [Instituto Dante Pazanezzi, Sao Paulo, SP (Brazil)

2011-07-01

Metanephric adenoma (MA), also designated nephrogenic nephroma or renal epithelial tumor resembling immature nephron, has just been recently recognized as a special type of benign renal epithelial tumor. Only few reports are found in the literature regarding this rare renal tumor. The purpose of this paper is to describe our clinical, imaging and histological / immunohistochemical observations of MA diagnosed in two patients and compare these data to previous information reported in medical databases (author)

Acute appendicitis in children: comparison of clinical diagnosis with ultrasound and CT imaging

International Nuclear Information System (INIS)

Karakas, S.P.; Guelfguat, M.; Springer, S.; Singh, S.P.; Leonidas, J.C.

2000-01-01

Background. There is strong evidence that imaging with ultrasound and CT can be of substantial diagnostic value in the diagnosis of acute appendicitis in children, but there is limited information of the impact of imaging on the management of these patients and its possible effect on surgical findings. Objective. We studied the impact of imaging in the management of acute appendicitis, in particular its effect on the rate of negative appendectomies and perforations. Patients and methods. We reviewed retrospectively the clinical records and imaging findings of 633 consecutive children and adolescents seen on an emergency basis with clinical suspicion of acute appendicitis. Two hundred seventy patients were operated upon on clinical evidence alone, while 360 were referred for US or CT, and occasionally both, because of doubtful clinical findings. Results. Acute appendicitis was found in 237 of those on clinical grounds alone, 68 of whom had perforation and related complications. Thus the rate of negative exploration and the rate of perforation were13 % and 29 %, respectively. One hundred eighty-two patients had preoperative US (sensitivity 74 %, specificity 94 %), 119 had CT (sensitivity 84 %, specificity 99 %), and 59 had both US and CT (sensitivity 75 %, specificity 100 %, but often with interpretation at variance with each other). The rate of negative appendectomy and perforation was 8 % and 23 %, respectively, for US, 5 % and 54 % for CT, and 9 % and 71 % when both examinations were performed. There is no statistical significance between the rates of diagnostic performance of US, CT, or their combination, nor between the negative appendectomy rates of each group, but the rate of perforation was significantly higher when CT was performed, alone or after US. Conclusion. The retrospective nature of the study prevents precise definition of the clinical characteristics and selection criteria for diagnostic examinations that may contribute to the management of children

Proposed alteration of images of molecular orbitals obtained using a scanning tunneling microscope as a probe of electron correlation.

Science.gov (United States)

Toroz, Dimitrios; Rontani, Massimo; Corni, Stefano

2013-01-04

Scanning tunneling spectroscopy (STS) allows us to image single molecules decoupled from the supporting substrate. The obtained images are routinely interpreted as the square moduli of molecular orbitals, dressed by the mean-field electron-electron interaction. Here we demonstrate that the effect of electron correlation beyond the mean field qualitatively alters the uncorrelated STS images. Our evidence is based on the ab initio many-body calculation of STS images of planar molecules with metal centers. We find that many-body correlations alter significantly the image spectral weight close to the metal center of the molecules. This change is large enough to be accessed experimentally, surviving to molecule-substrate interactions.

MCTP system model based on linear programming optimization of apertures obtained from sequencing patient image data maps

Energy Technology Data Exchange (ETDEWEB)

Ureba, A. [Dpto. Fisiología Médica y Biofísica. Facultad de Medicina, Universidad de Sevilla, E-41009 Sevilla (Spain); Salguero, F. J. [Nederlands Kanker Instituut, Antoni van Leeuwenhoek Ziekenhuis, 1066 CX Ámsterdam, The Nederlands (Netherlands); Barbeiro, A. R.; Jimenez-Ortega, E.; Baeza, J. A.; Leal, A., E-mail: alplaza@us.es [Dpto. Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, E-41009 Sevilla (Spain); Miras, H. [Servicio de Radiofísica, Hospital Universitario Virgen Macarena, E-41009 Sevilla (Spain); Linares, R.; Perucha, M. [Servicio de Radiofísica, Hospital Infanta Luisa, E-41010 Sevilla (Spain)

2014-08-15

irradiation case (Case II) solved with photon and electron modulated beams (IMRT + MERT); and a prostatic bed case (Case III) with a pronounced concave-shaped PTV by using volumetric modulated arc therapy. In the three cases, the required target prescription doses and constraints on organs at risk were fulfilled in a short enough time to allow routine clinical implementation. The quality assurance protocol followed to check CARMEN system showed a high agreement with the experimental measurements. Conclusions: A Monte Carlo treatment planning model exclusively based on maps performed from patient imaging data has been presented. The sequencing of these maps allows obtaining deliverable apertures which are weighted for modulation under a linear programming formulation. The model is able to solve complex radiotherapy treatments with high accuracy in an efficient computation time.

MCTP system model based on linear programming optimization of apertures obtained from sequencing patient image data maps

International Nuclear Information System (INIS)

Ureba, A.; Salguero, F. J.; Barbeiro, A. R.; Jimenez-Ortega, E.; Baeza, J. A.; Leal, A.; Miras, H.; Linares, R.; Perucha, M.

2014-01-01

irradiation case (Case II) solved with photon and electron modulated beams (IMRT + MERT); and a prostatic bed case (Case III) with a pronounced concave-shaped PTV by using volumetric modulated arc therapy. In the three cases, the required target prescription doses and constraints on organs at risk were fulfilled in a short enough time to allow routine clinical implementation. The quality assurance protocol followed to check CARMEN system showed a high agreement with the experimental measurements. Conclusions: A Monte Carlo treatment planning model exclusively based on maps performed from patient imaging data has been presented. The sequencing of these maps allows obtaining deliverable apertures which are weighted for modulation under a linear programming formulation. The model is able to solve complex radiotherapy treatments with high accuracy in an efficient computation time

MCTP system model based on linear programming optimization of apertures obtained from sequencing patient image data maps.

Science.gov (United States)

Ureba, A; Salguero, F J; Barbeiro, A R; Jimenez-Ortega, E; Baeza, J A; Miras, H; Linares, R; Perucha, M; Leal, A

2014-08-01

with photon and electron modulated beams (IMRT + MERT); and a prostatic bed case (Case III) with a pronounced concave-shaped PTV by using volumetric modulated arc therapy. In the three cases, the required target prescription doses and constraints on organs at risk were fulfilled in a short enough time to allow routine clinical implementation. The quality assurance protocol followed to check CARMEN system showed a high agreement with the experimental measurements. A Monte Carlo treatment planning model exclusively based on maps performed from patient imaging data has been presented. The sequencing of these maps allows obtaining deliverable apertures which are weighted for modulation under a linear programming formulation. The model is able to solve complex radiotherapy treatments with high accuracy in an efficient computation time.

Imaging and clinical analysis of 12 cases with melioidosis

International Nuclear Information System (INIS)

Yu Anle; Chen Hai; Li Qun

2007-01-01

Objective: Imaging and clinical manifestations of melioidosis were analyzed in order to improve our understanding of the disease and to reduce the rate of misdiagnosis. Methods: From 2001 to 2006, 12 melioidosis cases were confirmed by blood, pus and sputum culture. All cases were examined with radiography, and nine of them with CT and 2 with US. The imaging and clinical data were assessed retrospectively. Results: Ten of 12 cases revealed lung abnormalities, the main organ involved by melioidosis in the body. The appearances were observed as follows: diffused sheets and sheets fused partly in bilateral fields of the lungs can be seen on chest radiograph; homogeneous dense shadow of the lobe or segment were observed on plain chest film and CT; blurred strips radiated from hilum were revealed on plain chest film; multitude nodules in 2 lungs showed on CT; cavity with air and liquid be seen on plain chest film and CT; patches and granules in superior and middle fields or (and) inferior fields be seen on plain chest film and CT; arc shadow of water attenuation in dorsal thorax showed on CT. Infections outside the lung can be observed in orbital, lumbar muscle, liver and spleen in 1 case, and thighbone osteomyelitis with multi abscesses in one case. Conclusion: Alhough medioidosis has no characteristic imaging appearances, the disease's location, extent, severity and quantity objectively can be demonstrated by imaging, final confirmation is necessary using the culture of blood, pus and sputum. (authors)

Improvement of the clinical use of computed radiography for mobile chest imaging: Image quality and patient dose

Science.gov (United States)

Rill, Lynn Neitzey

Chest radiography is technically difficult because of the wide variation of tissue attenuations in the chest and limitations of screen-film systems. Mobile chest radiography, performed bedside on hospital inpatients, presents additional difficulties due to geometrical and equipment limitations inherent to mobile x-ray procedures and the severity of illness in patients. Computed radiography (CR) offers a new approach for mobile chest radiography by utilizing a photostimulable phosphor. Photostimulable phosphors are more efficient in absorbing lower-energy x-rays than standard intensifying screens and overcome some image quality limitations of mobile chest imaging, particularly because of the inherent latitude. This study evaluated changes in imaging parameters for CR to take advantage of differences between CR and screen-film radiography. Two chest phantoms, made of acrylic and aluminum, simulated x-ray attenuation for average-sized and large- sized adult chests. The phantoms contained regions representing the lungs, heart and subdiaphragm. Acrylic and aluminum disks (1.9 cm diameter) were positioned in the chest regions to make signal-to-noise ratio (SNR) measurements for different combinations of imaging parameters. Disk thicknesses (contrast) were determined from disk visibility. Effective dose to the phantom was also measured for technique combinations. The results indicated that using an anti-scatter grid and lowering x- ray tube potential improved the SNR significantly; however, the dose to the phantom also increased. An evaluation was performed to examine the clinical applicability of the observed improvements in SNR. Parameter adjustments that improved phantom SNRs by more than 50% resulted in perceived image quality improvements in the lung region of clinical mobile chest radiographs. Parameters that produced smaller improvements in SNR had no apparent effect on clinical image quality. Based on this study, it is recommended that a 3:1 grid be used for

MR imaging of pregnancy luteoma: a case report and correlation with the clinical features

Energy Technology Data Exchange (ETDEWEB)

Kao, Hung Wen; Wu, Ching Jiunn; Chung, Kuo Teng; Wang, Sheng Ru; Chen, Cheng Yu [Tri-Service General Hospital, National Defense Medical Center, Taipei (Taiwan)

2005-03-15

We report here on a 26-year-old pregnant female who developed hirsutism and virilization during her third trimester along with a significantly elevated serum testosterone level. Abdominal US and MR imaging studies were performed, and they showed unique imaging features that may suggest the diagnosis of pregnancy luteoma in the clinical context. After the delivery, the serum testosterone level continued to decrease, and it returned to normal three weeks postpartum. The follow-up imaging findings were closely correlated with the clinical presentation.

Body Dysmorphic Disorder and Other Clinically Significant Body Image Concerns in Adolescent Psychiatric Inpatients: Prevalence and Clinical Characteristics

Science.gov (United States)

Dyl, Jennifer; Kittler, Jennifer; Phillips, Katharine A.; Hunt, Jeffrey I.

2006-01-01

Background: This study assessed prevalence and clinical correlates of body dysmorphic disorder (BDD), eating disorders (ED), and other clinically significant body image concerns in 208 consecutively admitted adolescent inpatients. It was hypothesized that adolescents with BDD would have higher levels of depression, anxiety, and suicidality.…

The robustness of DLP hyperspectral imaging for clinical and surgical utility

Science.gov (United States)

Zuzak, Karel J.; Wehner, Eleanor; Rao, Shekar; Litorja, Maritoni; Allen, David W.; Singer, Mike; Purdue, Gary; Ufret-Vincenty, Rafael; White, Jonathan; Cadeddu, Jeffrey; Livingston, Edward

2010-02-01

Utilizing seed funding from Texas Instruments, a DLP (R)Hyperspectral Imaging system was developed by integrating a focal-plane array, FPA, detector with a DLP based spectrally tunable illumination source. Software is used to synchronize FPA with DLP hardware for collecting spectroscopic images as well as running novel illumination schemes and chemometric deconvolution methods for producing gray scale or color encoded images visualizing molecular constituents at video rate. Optical spectra and spectroscopic image data of a variety of live human organs and diseased tissue collected from patients during surgical procedures and clinical visits being cataloged for a database will be presented.

Fractal analysis of en face tomographic images obtained with full field optical coherence tomography

Energy Technology Data Exchange (ETDEWEB)

Gao, Wanrong; Zhu, Yue [Department of Optical Engineering, Nanjing University of Science and Technology, Jiangsu (China)

2017-03-15

The quantitative modeling of the imaging signal of pathological areas and healthy areas is necessary to improve the specificity of diagnosis with tomographic en face images obtained with full field optical coherence tomography (FFOCT). In this work, we propose to use the depth-resolved change in the fractal parameter as a quantitative specific biomarker of the stages of disease. The idea is based on the fact that tissue is a random medium and only statistical parameters that characterize tissue structure are appropriate. We successfully relate the imaging signal in FFOCT to the tissue structure in terms of the scattering function and the coherent transfer function of the system. The formula is then used to analyze the ratio of the Fourier transforms of the cancerous tissue to the normal tissue. We found that when the tissue changes from the normal to cancerous the ratio of the spectrum of the index inhomogeneities takes the form of an inverse power law and the changes in the fractal parameter can be determined by estimating slopes of the spectra of the ratio plotted on a log-log scale. The fresh normal and cancer liver tissues were imaged to demonstrate the potential diagnostic value of the method at early stages when there are no significant changes in tissue microstructures. (copyright 2016 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Building Imaging Institutes of Patient Care Outcomes: Imaging as a Nidus for Innovation in Clinical Care, Research, and Education.

Science.gov (United States)

Petrou, Myria; Cronin, Paul; Altaee, Duaa K; Kelly, Aine M; Foerster, Bradley R

2018-05-01

Traditionally, radiologists have been responsible for the protocol of imaging studies, imaging acquisition, supervision of imaging technologists, and interpretation and reporting of imaging findings. In this article, we outline how radiology needs to change and adapt to a role of providing value-based, integrated health-care delivery. We believe that the way to best serve our specialty and our patients is to undertake a fundamental paradigm shift in how we practice. We describe the need for imaging institutes centered on disease entities (eg, lung cancer, multiple sclerosis) to not only optimize clinical care and patient outcomes, but also spur the development of a new educational focus, which will increase opportunities for medical trainees and other health professionals. These institutes will also serve as unique environments for testing and implementing new technologies and for generating new ideas for research and health-care delivery. We propose that the imaging institutes focus on how imaging practices-including new innovations-improve patient care outcomes within a specific disease framework. These institutes will allow our specialty to lead patient care, provide the necessary infrastructure for state-of-the art-education of trainees, and stimulate innovative and clinically relevant research. Copyright © 2018 The Association of University Radiologists. All rights reserved.

Clinical value of SPECT/CT imaging in the diagnosis of bone metastasis

International Nuclear Information System (INIS)

Wang Xinhua; Zhao Yanping; Lu Haijian; Dong Zhanfei

2010-01-01

Objective: To evaluate the clinical value of 99 Tc m -methylene diphosphonic acid (MDP) SPECT/CT imaging for the diagnosis of bone metastasis. Methods: Patients suspected for bone metastasis and with bone pain of unknown origin were included in this study (n=237). All cases underwent SPECT and CT imaging at 180 min after 99 Tc m -MDP injection. Diagnosis was confirmed by pathology (n=21), more than 2 kinds of radiologieal imaging (MRI, CT, X-ray) (n=106), and clinical follow up in 2 years (n=110). χ 2 -test was used to compare the results of planar and SPECT/CT imaging using SAS 6.12 software. Results: In 237 patients, planar imaging of 142 cases matched the final diagnosis in which 72 had benign lesions and 70 had bone metastases. The definite coincidence rate was 95.30% (142/149). SPECT/CT imaging of 224 cases matched the final diagnosis in which 104 had benign lesions and 120 cases diagnosed as bone metastases. The coincidence and definite coincidence rates were 94.51% (224/237), and 99.48% (192/193). Difference in the definite coincidence rate between planar and SPECT/CT imaging was statistically significant (χ 2 = 5.37, P=0.024). Conclusion: SPECT/CT imaging is valuable for accurate localization of osseous pathology and for improvement of diagnosing bone metastasis. (authors)

The clinical evaluation of combining radionuclide imaging with radioimmunoassay for hashimoto's thyroiditis

International Nuclear Information System (INIS)

Huang Chenggang; Chen Xiaoyan; Deng Yan

2003-01-01

By analysing nuclide image characteristics and radioimmunoassay data of 61 cases with Hashimoto's thyroiditis (HT), HT can be classified five types as below: uneven distribution, diffusion, with hyperfunction, with nodules, nearly normal. The results of radionuclide imaging and the radioimmunoassay of all the types indicate that HT can be preliminarily diagnosed by conscientiously analysing nuclide image characteristics and radioimmunoassay data and linking clinical symptoms and signs

Indications, advantages and limitations of perinatal postmortem imaging in clinical practice

International Nuclear Information System (INIS)

Arthurs, Owen J.; Taylor, Andrew M.; Sebire, Neil J.

2015-01-01

Just as there is a range of paediatric imaging techniques available during life, a similar repertoire is available as part of the foetal and perinatal postmortem examination. In this article, we review the literature regarding the diagnostic utility of postmortem radiography, US, CT and MRI in this clinical setting. There is limited direct evidence on the diagnostic utility of any of these techniques, apart from postmortem MRI, which when combined with other noninvasive investigations, has been shown to be highly sensitive and specific for many foetal postmortem diagnoses. The main disadvantages of postmortem MRI include the longer duration of imaging, the need for appropriate training in the interpretation of normal postmortem changes, and possible non-diagnostic imaging examinations in early gestation fetuses. As less-invasive autopsy becomes increasingly available, the true utility of these techniques will evolve, and clinical guidelines for maximal diagnostic yield can be developed. (orig.)

Indications, advantages and limitations of perinatal postmortem imaging in clinical practice

Energy Technology Data Exchange (ETDEWEB)

Arthurs, Owen J. [Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Radiology, London (United Kingdom); University College London, Institute of Child Health, London (United Kingdom); Taylor, Andrew M. [Great Ormond Street Hospital for Children NHS Foundation Trust, Cardiorespiratory Division, London (United Kingdom); Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science, London (United Kingdom); Sebire, Neil J. [University College London, Institute of Child Health, London (United Kingdom); Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Histopathology, London (United Kingdom)

2015-04-01

Just as there is a range of paediatric imaging techniques available during life, a similar repertoire is available as part of the foetal and perinatal postmortem examination. In this article, we review the literature regarding the diagnostic utility of postmortem radiography, US, CT and MRI in this clinical setting. There is limited direct evidence on the diagnostic utility of any of these techniques, apart from postmortem MRI, which when combined with other noninvasive investigations, has been shown to be highly sensitive and specific for many foetal postmortem diagnoses. The main disadvantages of postmortem MRI include the longer duration of imaging, the need for appropriate training in the interpretation of normal postmortem changes, and possible non-diagnostic imaging examinations in early gestation fetuses. As less-invasive autopsy becomes increasingly available, the true utility of these techniques will evolve, and clinical guidelines for maximal diagnostic yield can be developed. (orig.)

Functional brain imaging in the clinical assessment of consciousness.

Directory of Open Access Journals (Sweden)

Michael S Rafii

2010-11-01

Full Text Available Recent findings suggest that functional brain imaging might be used to identify consciousness in patients diagnosed with persistent vegetative state and minimally conscious state. Michael Rafii and James Brewer discuss the potential for fMRI's wider implementation in clinical practice, and associated caveats.

Overhauser-enhanced MR imaging (OMRI)

International Nuclear Information System (INIS)

Golman, K.; Leunbach, I.; Ardenkjaer-Larsen, J.H.; Wistrand, L.G.; Petersson, J.S.; Ehnholm, G.J.; Jaervi, A.; Vahasalo, S.

1998-01-01

Purpose: To evaluate a new single-electron contrast agent for Overhauser-enhanced MR imaging. The contrast agents that are currently available give enhancement factors that are too low to make the technique a valid option for routine clinical use. Material and Methods: MR images were generated directly following the injection of the substance into rats. The MR scanner was operated at a main magnetic field of 0.01 T and equipped with a separate rf-transmitter tuned to the electron paramagnetic resonance frequency of the contrast agent. Results: As expected, the images generated show a high level of enhancement in areas where the contrast agent was present, and a maximum enhancement of 60 times the normal proton signal was obtained in the vascular area. The signal-to-noise ratios in the images were superior to those previously attained. Conclusion: The new contrast agent makes it possible to generate MR images with both morphological and functional information at 0.01 T. The signal-to-noise ratios found in the generated images were of the same order as, or better than, those obtained with the standard clinical routine. (orig.)

Consensus recommendations for a standardized Brain Tumor Imaging Protocol in clinical trials

NARCIS (Netherlands)

B.M. Ellingson (Benjamin M.); M. Bendszus (Martin); J. Boxerman (Jerrold); D. Barboriak (Daniel); B.J. Erickson (Bradley J.); M. Smits (Marion); S.J. Nelson (Sarah J.); E. Gerstner (Elizabeth); B. Alexander (Brian); G. Goldmacher (Gregory); W. Wick (Wolfgang); M.A. Vogelbaum (Michael); M. Weller (Michael); E. Galanis (Evanthia); J. Kalpathy-Cramer (Jayashree); L. Shankar; P. Jacobs (Paula); W.B. Pope (Whitney B.); D. Yang (Dewen); C. Chung (Caroline); R.H. Knopp; S. Cha (Soonme); M.J. van den Bent (Martin); S.M. Chang (Susan); W.K. Al Yung; T.F. Cloughesy (Timothy F.); P.Y. Wen (Patrick Y.); M.R. Gilbert (Mark R.); A. Whitney (Andrew); D. Sandak (David); A. Musella (Al); C. Haynes (Chas); M. Wallace (Max); D.F. Arons (David F.); A. Kingston (Ann)

2015-01-01

textabstractA recent joint meeting was held on January 30, 2014, with the US Food and Drug Administration (FDA), National Cancer Institute (NCI), clinical scientists, imaging experts, pharmaceutical and biotech companies, clinical trials cooperative groups, and patient advocate groups to discuss

Feasibility of using 'lung density' values estimated from EIT images for clinical diagnosis of lung abnormalities in mechanically ventilated ICU patients.

Science.gov (United States)

Nebuya, Satoru; Koike, Tomotaka; Imai, Hiroshi; Iwashita, Yoshiaki; Brown, Brian H; Soma, Kazui

2015-06-01

This paper reports on the results of a study which compares lung density values obtained from electrical impedance tomography (EIT), clinical diagnosis and CT values (HU) within a region of interest in the lung. The purpose was to assess the clinical use of lung density estimation using EIT data. In 11 patients supported by a mechanical ventilator, the consistency of regional lung density measurements as estimated by EIT was validated to assess the feasibility of its use in intensive care medicine. There were significant differences in regional lung densities recorded in the supine position between normal lungs and diseased lungs associated with pneumonia, atelectasis and pleural effusion (normal; 240 ± 71.7 kg m(-3), pneumonia; 306 ± 38.6 kg m(-3), atelectasis; 497 ± 130 kg m(-3), pleural effusion; 467 ± 113 kg m(-3): Steel-Dwass test, p EIT images. The results of CT and EIT images from five patients in an intensive care unit showed a correlation coefficient of 0.66 ± 0.13 between the CT values (HU) and the lung density values (kg m(-3)) obtained from EIT. These results indicate that it may be possible to obtain a quantitative value for regional lung density using EIT.

Clinical evaluation of Synthetic Aperture Sequential Beamforming and Tissue Harmonic Imaging

DEFF Research Database (Denmark)

Brandt, Andreas Hjelm; Hemmsen, Martin Christian; Hansen, Peter Møller

2014-01-01

This study determines if the data reduction achieved by the combination Synthetic Aperture Sequential Beamforming (SASB) and Tissue Harmonic Imaging (THI) affects image quality. SASB-THI was evaluated against the combination of Dynamic Received Focusing and Tissue Harmonic Imaging (DRF-THI). A BK...... equally good image quality although a data reduction of 64 times is achieved with SASB-THI.......This study determines if the data reduction achieved by the combination Synthetic Aperture Sequential Beamforming (SASB) and Tissue Harmonic Imaging (THI) affects image quality. SASB-THI was evaluated against the combination of Dynamic Received Focusing and Tissue Harmonic Imaging (DRF-THI). A BK...... liver pathology were scanned to set a clinical condition, where ultrasonography is often performed. A total of 114 sequences were recorded and evaluated by five radiologists. The evaluators were blinded to the imaging technique, and each sequence was shown twice with different left-right positioning...

Imaging systems and methods for obtaining and using biometric information

Science.gov (United States)

McMakin, Douglas L [Richland, WA; Kennedy, Mike O [Richland, WA

2010-11-30

Disclosed herein are exemplary embodiments of imaging systems and methods of using such systems. In one exemplary embodiment, one or more direct images of the body of a clothed subject are received, and a motion signature is determined from the one or more images. In this embodiment, the one or more images show movement of the body of the subject over time, and the motion signature is associated with the movement of the subject's body. In certain implementations, the subject can be identified based at least in part on the motion signature. Imaging systems for performing any of the disclosed methods are also disclosed herein. Furthermore, the disclosed imaging, rendering, and analysis methods can be implemented, at least in part, as one or more computer-readable media comprising computer-executable instructions for causing a computer to perform the respective methods.

Contrast-enhanced magnetic resonance imaging of pulmonary lesions: Description of a technique aiming clinical practice

International Nuclear Information System (INIS)

Koenigkam-Santos, Marcel; Optazaite, Elzbieta; Sommer, Gregor; Safi, Seyer; Heussel, Claus Peter; Kauczor, Hans-Ulrich

2015-01-01

To propose a technique for evaluation of pulmonary lesions using contrast-enhanced MRI; to assess morphological patterns of enhancement and correlate quantitative analysis with histopathology. Material and methods: Thirty-six patients were prospectively studied. Volumetric-interpolated T1W images were obtained during consecutive breath holds after bolus triggered contrast injection. Volume coverage of first three acquisitions was limited (higher temporal resolution) and last acquisition obtained at 4th min. Two radiologists individually evaluated the patterns of enhancement. Region-of-interest-based signal intensity (SI)-time curves were created to assess quantitative parameters. Results: Readers agreed moderately to substantially concerning lesions’ enhancement pattern. SI-time curves could be created for all lesions. In comparison to benign, malignant lesions showed higher values of maximum enhancement, early peak, slope and 4th min enhancement. Early peak >15% showed 100% sensitivity to detect malignancy, maximum enhancement >40% showed 100% specificity. Conclusions: The proposed technique is robust, simple to perform and can be applied in clinical scenario. It allows visual evaluation of enhancement pattern/progression together with creation of SI-time curves and assessment of derived quantitative parameters. Perfusion analysis was highly sensitive to detect malignancy, in accordance to what is recommended by most recent guidelines on imaging evaluation of pulmonary lesions

Contrast-enhanced magnetic resonance imaging of pulmonary lesions: Description of a technique aiming clinical practice

Energy Technology Data Exchange (ETDEWEB)

Koenigkam-Santos, Marcel, E-mail: marcelk46@yahoo.com.br [Department of Diagnostic and Interventional Radiology, University of Heidelberg, Im Neuenheimer Feld 110, 69120 Heidelberg (Germany); Radiology Department, German Cancer Research Center (Deutsches Krebsforschungszentrum – DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Department of Radiology, University Hospital of the School of Medicine of Ribeirao Preto, University of Sao Paulo, Avenida Bandeirantes 3900, Campus Universitario Monte Alegre, 14048 900 Ribeirao Preto, Sao Paulo (Brazil); Optazaite, Elzbieta, E-mail: optazaite@andrulis.eu [Diagnostic and Interventional Radiology with Nuclear Medicine, Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstraße 5, 69126 Heidelberg (Germany); Sommer, Gregor, E-mail: gregor.sommer@usb.ch [Clinic of Radiology and Nuclear Medicine, University Hospital Basel, Petersgraben 4, CH-4031 Basel (Switzerland); Safi, Seyer, E-mail: seyer.safi@gmail.com [Surgery Department, Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstraße 5, 69126 Heidelberg (Germany); Heussel, Claus Peter, E-mail: heussel@uni-heidelberg.de [Diagnostic and Interventional Radiology with Nuclear Medicine, Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstraße 5, 69126 Heidelberg (Germany); Translational Lung Research Center (TLRC), Member of the German Center for Lung Research (DZL), Im Neuenheimer Feld 350, 69120 Heidelberg (Germany); Kauczor, Hans-Ulrich, E-mail: hans-ulrich.kauczor@med.uni-heidelberg.de [Department of Diagnostic and Interventional Radiology, University of Heidelberg, Im Neuenheimer Feld 110, 69120 Heidelberg (Germany); Translational Lung Research Center (TLRC), Member of the German Center for Lung Research (DZL), Im Neuenheimer Feld 350, 69120 Heidelberg (Germany); and others

2015-01-15

To propose a technique for evaluation of pulmonary lesions using contrast-enhanced MRI; to assess morphological patterns of enhancement and correlate quantitative analysis with histopathology. Material and methods: Thirty-six patients were prospectively studied. Volumetric-interpolated T1W images were obtained during consecutive breath holds after bolus triggered contrast injection. Volume coverage of first three acquisitions was limited (higher temporal resolution) and last acquisition obtained at 4th min. Two radiologists individually evaluated the patterns of enhancement. Region-of-interest-based signal intensity (SI)-time curves were created to assess quantitative parameters. Results: Readers agreed moderately to substantially concerning lesions’ enhancement pattern. SI-time curves could be created for all lesions. In comparison to benign, malignant lesions showed higher values of maximum enhancement, early peak, slope and 4th min enhancement. Early peak >15% showed 100% sensitivity to detect malignancy, maximum enhancement >40% showed 100% specificity. Conclusions: The proposed technique is robust, simple to perform and can be applied in clinical scenario. It allows visual evaluation of enhancement pattern/progression together with creation of SI-time curves and assessment of derived quantitative parameters. Perfusion analysis was highly sensitive to detect malignancy, in accordance to what is recommended by most recent guidelines on imaging evaluation of pulmonary lesions.

Bioluminescent imaging: a critical tool in pre-clinical oncology research.

LENUS (Irish Health Repository)

O'Neill, Karen

2010-02-01

Bioluminescent imaging (BLI) is a non-invasive imaging modality widely used in the field of pre-clinical oncology research. Imaging of small animal tumour models using BLI involves the generation of light by luciferase-expressing cells in the animal following administration of substrate. This light may be imaged using an external detector. The technique allows a variety of tumour-associated properties to be visualized dynamically in living models. The increasing use of BLI as a small-animal imaging modality has led to advances in the development of xenogeneic, orthotopic, and genetically engineered animal models expressing luciferase genes. This review aims to provide insight into the principles of BLI and its applications in cancer research. Many studies to assess tumour growth and development, as well as efficacy of candidate therapeutics, have been performed using BLI. More recently, advances have also been made using bioluminescent imaging in studies of protein-protein interactions, genetic screening, cell-cycle regulators, and spontaneous cancer development. Such novel studies highlight the versatility and potential of bioluminescent imaging in future oncological research.

Comparison of Measurements of the Uterus and Cervix Obtained by Magnetic Resonance and Transabdominal Ultrasound Imaging to Identify the Brachytherapy Target in Patients With Cervix Cancer

International Nuclear Information System (INIS)

Dyk, Sylvia van; Kondalsamy-Chennakesavan, Srinivas; Schneider, Michal; Bernshaw, David; Narayan, Kailash

2014-01-01

Purpose: To compare measurements of the uterus and cervix obtained with magnetic resonance imaging (MRI) and transabdominal ultrasound to determine whether ultrasound can identify the brachytherapy target and be used to guide conformal brachytherapy planning and treatment for cervix cancer. Methods and Materials: Consecutive patients undergoing curative treatment with radiation therapy between January 2007 and March 2012 were included in the study. Intrauterine applicators were inserted into the uterine canal while patients were anesthetized. Images were obtained by MRI and transabdominal ultrasound in the longitudinal axis of the uterus with the applicator in treatment position. Measurements were taken at the anterior and posterior surface of the uterus at 2.0-cm intervals along the applicator, from the external os to the tip of the applicator. Data were analyzed using Bland Altman plots examining bias and 95% limits of agreement. Results: A total of 192 patients contributed 1668 measurements of the cervix and uterus. Mean (±SD) differences of measurements between imaging modalities at the anterior and posterior uterine surface ranged from 1.5 (±3.353) mm to 3.7 (±3.856) mm, and −1.46 (±3.308) mm to 0.47 (±3.502) mm, respectively. The mean differences were less than 3 mm in the cervix. The mean differences were less than 1.5 mm at all measurement points on the posterior surface. Conclusion: Differences in the measurements of the cervix and uterus obtained by MRI and ultrasound were within clinically acceptable limits. Transabdominal ultrasound can be substituted for MRI in defining the target volume for conformal brachytherapy treatment of cervix cancer

Comparison of Measurements of the Uterus and Cervix Obtained by Magnetic Resonance and Transabdominal Ultrasound Imaging to Identify the Brachytherapy Target in Patients With Cervix Cancer

Energy Technology Data Exchange (ETDEWEB)

Dyk, Sylvia van, E-mail: sylvia.vandyk@petermac.org [Radiation Therapy Services, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Kondalsamy-Chennakesavan, Srinivas [Rural Clinical School, University of Queensland, Toowoomba, Queensland (Australia); Schneider, Michal [Department of Medical Imaging and Radiation Science, Monash University, Clayton, Victoria (Australia); Bernshaw, David [Division of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Narayan, Kailash [Division of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Department of Obstetrics and Gynaecology, Melbourne University, Melbourne, Victoria (Australia)

2014-03-15

Purpose: To compare measurements of the uterus and cervix obtained with magnetic resonance imaging (MRI) and transabdominal ultrasound to determine whether ultrasound can identify the brachytherapy target and be used to guide conformal brachytherapy planning and treatment for cervix cancer. Methods and Materials: Consecutive patients undergoing curative treatment with radiation therapy between January 2007 and March 2012 were included in the study. Intrauterine applicators were inserted into the uterine canal while patients were anesthetized. Images were obtained by MRI and transabdominal ultrasound in the longitudinal axis of the uterus with the applicator in treatment position. Measurements were taken at the anterior and posterior surface of the uterus at 2.0-cm intervals along the applicator, from the external os to the tip of the applicator. Data were analyzed using Bland Altman plots examining bias and 95% limits of agreement. Results: A total of 192 patients contributed 1668 measurements of the cervix and uterus. Mean (±SD) differences of measurements between imaging modalities at the anterior and posterior uterine surface ranged from 1.5 (±3.353) mm to 3.7 (±3.856) mm, and −1.46 (±3.308) mm to 0.47 (±3.502) mm, respectively. The mean differences were less than 3 mm in the cervix. The mean differences were less than 1.5 mm at all measurement points on the posterior surface. Conclusion: Differences in the measurements of the cervix and uterus obtained by MRI and ultrasound were within clinically acceptable limits. Transabdominal ultrasound can be substituted for MRI in defining the target volume for conformal brachytherapy treatment of cervix cancer.

Imaging tissue hypoxia: clinical and pre-clinical experience with 123IAZA

International Nuclear Information System (INIS)

Wiebe, L.I.

1997-01-01

The molecular mechanisms that underline the selective binding of iodazomycin arabinoside, IAZA, and related nitromidazoles are reviewed as a basis for interpretation of preclinical and clinical data for hypoxic binding of radioiodinated IAZA. Clinical data are presented for 123 IAZA uptake in a number of pathologies including metastatic tumours, peripheral vascular disease in diabetes, muscle stress and rheumatoid arthritis. The results of studies to determine the influence of tumour type on uptake of 123 I-IAZA in patients with a variety of deep-seated solid tumours will be presented. Correlations of hypoxia-dependent binding with 99m Tc-HMPAO perfusion images will be reviewed and early correlations of uptake to treatment response in cancer will be presented. Unusual features of 123 I-IAZA biodistribution will also be discussed together with detailed pharmacokinetic and radiation dosimetry data for '2 123 I- IAZA in normal volunteers

Clinical applications of SPECT/CT: New hybrid nuclear medicine imaging system

International Nuclear Information System (INIS)

2008-08-01

Interest in multimodality imaging shows no sign of subsiding. New tracers are spreading out the spectrum of clinical applications and innovative technological solutions are preparing the way for yet more modality marriages: hybrid imaging. Single photon emission computed tomography (SPECT) has enabled the evaluation of disease processes based on functional and metabolic information of organs and cells. Integration of X ray computed tomography (CT) into SPECT has recently emerged as a brilliant diagnostic tool in medical imaging, where anatomical details may delineate functional and metabolic information. SPECT/CT has proven to be valuable in oncology. For example, in the case of a patient with metastatic thyroid cancer, neither SPECT nor CT alone could identify the site of malignancy. SPECT/CT, a hybrid image, precisely identified where the surgeon should operate. However SPECT/CT is not just advantageous in oncology. It may also be used as a one-stop-shop for various diseases. Clinical applications with SPECT/CT have started and expanded in developed countries. It has been reported that moving from SPECT alone to SPECT/CT could change diagnoses in 30% of cases. Large numbers of people could therefore benefit from this shift all over the world. This report presents an overview of clinical applications of SPECT/CT and a relevant source of information for nuclear medicine physicians, radiologists and clinical practitioners. This information may also be useful for decision making when allocating resources dedicated to the health care system, a critical issue that is especially important for the development of nuclear medicine in developing countries. In this regard, the IAEA may be heavily involved in the promotion of programmes aimed at the IAEA's coordinated research projects and Technical Cooperation projects

Computed tomography image of the mediastinal and axillary lymph nodes in clinically sound Rottweilers

Directory of Open Access Journals (Sweden)

Ana Carolina B. Fonseca Pinto

2013-03-01

Full Text Available Trough computed tomography (CT, it is possible to evaluate lymph nodes in detail and to detect changes in these structures earlier than with radiographs and ultrasound. Lack of information in the veterinary literature directed the focus of this report to normal aspects of the axillary and mediastinal lymph nodes of adult dogs on CT imaging. A CT scan of 15 normal adult male and female Rottweilers was done. To define them as clinically sound, anamnesis, physical examination, complete blood count, renal and hepatic biochemistry, ECG, and thoracic radiographs were performed. After the intravenous injection of hydrosoluble ionic iodine contrast medium contiguous 10mm in thickness thoracic transverse images were obtained with an axial scanner. In the obtained images mediastinal and axillary lymph nodes were sought and when found measured in their smallest diameter and their attenuation was compared to musculature. Mean and standard deviation of: age, weight, body length and the smallest diameter of the axillary and mediastinal lymph nodes were determined. Mean and standard deviation of parameters: age 3.87±2.03 years, weight 41.13±5.12, and body length 89.61±2.63cm. Axillary lymph nodes were seen in 60% of the animals, mean of the smallest diameter was 3.58mm with a standard deviation of 2.02 and a minimum value of 1mm and a maximum value of 7mm. From 13 observed lymph nodes 61.53% were hypopodense when compared with musculature, and 30.77% were isodense. Mediastinal lymph nodes were identified in 73.33% of the dogs; mean measure of the smallest diameter was 4.71mm with a standard deviation of 2.61mm and a minimum value of 1mm, and a maximum value of 8mm. From 14 observed lymph nodes 85.71% were isodense when compared with musculature and 14.28% were hypodense. The results show that it is possible to visualize axillary and mediastinal lymph nodes in adult clinically sound Rottweilers with CT using a slice thickness and interval of 10mm. The

Nasolabial cyst: presentation of a clinical case with CT and MR images.

Science.gov (United States)

Aquilino, Raphael Navarro; Bazzo, Vitor José; Faria, Reinaldo José Antônio; Eid, Nayene Leocádia Manzutti; Bóscolo, Frab Norberto

2008-01-01

The nasolabial cyst is an uncommon non-odontogenic cyst that develops in the lower region of the nasal ala; its pathogenesis is uncertain. This lesion grows slowly and measures between 1.5 and 3 cm; it is characterized clinically by a floating tumefaction in the nasolabial sulcus, which elevates the upper lip. The diagnosis is based on the clinical findings and, if necessary, image exams. This paper reports a case of a white 48-year-old Brazilian female patient that presented a firm tumor in the left ala of the nose; the clinical features suggested a nasolabial cyst. CT scans revealed an expanding tumor with soft tissue density located in the left ala of the nose. It measured 1.2 cm in diameter and had a clear and well-defined outline; its homogeneous density was about 50 HU. MR images revealed a circular lesion located in soft tissue; T1 and T2 weighted signals were hyperintense, as were images after fat suppression. The diagnosis was a nasolabial cyst, which was confirmed by histopathology after surgery.

Clinical application of domestica manufactured BHP6601 SPECT

International Nuclear Information System (INIS)

Zhang Shuwen; Tian Jiahe; Liu Zilai; He Yijie; Shao Mingzhe; Zhang Jinming

2005-01-01

Clinical imaging of 150 patients with varying demand is carried out with BHP6601 SPECT manufactured locally, and the results are compared with that obtained by an E. CAM system manufactured by Siemens. The results show that BHP6601 had an acceptable and stable performance from a technical point of view. It offers a sufficient ability for organ imaging of clinical requirement. (authors)

DARTFire Sees Microgravity Fires in a New Light--Large Data Base of Images Obtained

Science.gov (United States)

Olson, Sandra L.; Hegde, Uday; Altenkirch, Robert A.; Bhatacharjee, Subrata

1999-01-01

The recently completed DARTFire sounding rocket microgravity combustion experiment launched a new era in the imaging of flames in microgravity. DARTFire stands for "Diffusive and Radiative Transport in Fires," which perfectly describes the two primary variables--diffusive flow and radiation effects--that were studied in the four launches of this program (June 1996 to September 1997). During each launch, two experiments, which were conducted simultaneously during the 6 min of microgravity, obtained results as the rocket briefly exited the Earth s atmosphere.

Alternative positron emission tomography with non-conventional positron emitters: effects of their physical properties on image quality and potential clinical applications

International Nuclear Information System (INIS)

Pagani, M.; Stone-Elander, S.; Larsson, S.A.

1997-01-01

The increasing amount of clinically relevant information obtained by positron emission tomography (PET), primarily with fluorine-18 labelled 2-deoxy-2-fluoro-d-glucose, has generated a demand for new routes for the widespread and cost-efficient use of positron-emitting radiopharmaceuticals. New dual-head single-photon emission tomography (SPET) cameras are being developed which offer coincidence detection with camera heads lacking a collimator or SPET imaging with specially designed collimators and additional photon shielding. Thus, not only satellite PET imaging units but also nuclear medicine units investing in these new SPET/PET systems need to examine all available alternatives for rational radionuclide supplies from host cyclotrons. This article examines 25 ''alternative'' positron-emitting radionuclides, discusses the impact of their decay properties on image quality and reviews methods for their production as well as for their application in imaging techniques. (orig.)

LesionTracker: Extensible Open-Source Zero-Footprint Web Viewer for Cancer Imaging Research and Clinical Trials.

Science.gov (United States)

Urban, Trinity; Ziegler, Erik; Lewis, Rob; Hafey, Chris; Sadow, Cheryl; Van den Abbeele, Annick D; Harris, Gordon J

2017-11-01

Oncology clinical trials have become increasingly dependent upon image-based surrogate endpoints for determining patient eligibility and treatment efficacy. As therapeutics have evolved and multiplied in number, the tumor metrics criteria used to characterize therapeutic response have become progressively more varied and complex. The growing intricacies of image-based response evaluation, together with rising expectations for rapid and consistent results reporting, make it difficult for site radiologists to adequately address local and multicenter imaging demands. These challenges demonstrate the need for advanced cancer imaging informatics tools that can help ensure protocol-compliant image evaluation while simultaneously promoting reviewer efficiency. LesionTracker is a quantitative imaging package optimized for oncology clinical trial workflows. The goal of the project is to create an open source zero-footprint viewer for image analysis that is designed to be extensible as well as capable of being integrated into third-party systems for advanced imaging tools and clinical trials informatics platforms. Cancer Res; 77(21); e119-22. ©2017 AACR . ©2017 American Association for Cancer Research.

MR imaging of tibial collateral ligament injury: comparison with clinical examination

International Nuclear Information System (INIS)

Yao, L.; Dungan, D.; Seeger, L.L.

1994-01-01

We sought to clarify the capability of routine magnetic resonance (MR) imaging of the knee to detect and grade tibial collateral ligament (TCL) injury. We also wanted to define the exact MR findings that were the most important for diagnosis. Sixty-three patients were clinically evaluated for TCL injury prior to MR imaging of the knee on a 1.5-tesla system. MR studies were scored with respect to multiple direct and indirect findings. By discriminant analysis, the overall accuracy of classification (into clinical grades 1, 2, 3 and normal) on the basis of MR was 65%. Accuracy for detection of abnormal TCLs was 87%. The most useful MR findings for detection and grading of TCL injury were direct signs: subcutaneous edema over the TCL, focal disruption of the TCL, increased signal in the TCL on T2-weighted images, and longitudinal striations within the TCL. Indirect signs such as trabecular trauma were less useful for TCL evaluation. The presence of a tear of the anterior cruciate ligament, however, correlated with TCL injury of a higher grade. T2-weighted coronal images, by better depicting intraligamentous edema and fiber disruption, improved the MR assessment of the TCL. (orig.)

Clinical and imaging correlates of amyloid deposition in dementia with Lewy bodies.

Science.gov (United States)

Donaghy, Paul C; Firbank, Michael J; Thomas, Alan J; Lloyd, Jim; Petrides, George; Barnett, Nicola; Olsen, Kirsty; O'Brien, John T

2018-04-19

Amyloid deposition is common in dementia with Lewy bodies, but its pathophysiological significance is unclear. The objective of this study was to investigate the relationship between amyloid deposition and clinical profile, gray matter volume, and brain perfusion in dementia with Lewy bodies. Dementia with Lewy bodies (n = 37), Alzheimer's disease (n = 20), and controls (n = 20) underwent a thorough clinical assessment, 3T MRI, and early- and late-phase 18 F-Florbetapir PET-CT to assess cortical perfusion and amyloid deposition, respectively. Amyloid scans were visually categorized as positive or negative. Image analysis was carried out using statistical parametric mapping (SPM) 8. There were no significant differences between amyloid-positive and amyloid-negative dementia with Lewy bodies cases in age (P = .78), overall cognitive impairment (P = .83), level of functional impairment (P = .80), or any other clinical or cognitive scale. There were also no significant differences in hippocampal or gray matter volumes. However, amyloid-positive dementia with Lewy bodies cases had lower medial temporal lobe perfusion (P = .03) than amyloid-negative cases, although a combination of medial temporal lobe perfusion, hippocampal volume, and cognitive measures was unable to accurately predict amyloid status in dementia with Lewy bodies. Amyloid deposition was not associated with differences in clinical or neuropsychological profiles in dementia with Lewy bodies, but was associated with imaging evidence of medial temporal lobe dysfunction. The presence of amyloid in dementia with Lewy bodies cannot be identified on the basis of clinical and other imaging features and will require direct assessment via PET imaging or CSF. © 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society. © 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf

Cardiac hybrid imaging

Energy Technology Data Exchange (ETDEWEB)

Gaemperli, Oliver [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); University Hospital Zurich, Nuclear Cardiology, Cardiovascular Center, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland)

2014-05-15

Hybrid cardiac single photon emission computed tomography (SPECT)/CT imaging allows combined assessment of anatomical and functional aspects of cardiac disease. In coronary artery disease (CAD), hybrid SPECT/CT imaging allows detection of coronary artery stenosis and myocardial perfusion abnormalities. The clinical value of hybrid imaging has been documented in several subsets of patients. In selected groups of patients, hybrid imaging improves the diagnostic accuracy to detect CAD compared to the single imaging techniques. Additionally, this approach facilitates functional interrogation of coronary stenoses and guidance with regard to revascularization procedures. Moreover, the anatomical information obtained from CT coronary angiography or coronary artery calcium scores (CACS) adds prognostic information over perfusion data from SPECT. The use of cardiac hybrid imaging has been favoured by the dissemination of dedicated hybrid systems and the release of dedicated image fusion software, which allow simple patient throughput for hybrid SPECT/CT studies. Further technological improvements such as more efficient detector technology to allow for low-radiation protocols, ultra-fast image acquisition and improved low-noise image reconstruction algorithms will be instrumental to further promote hybrid SPECT/CT in research and clinical practice. (orig.)

Practical evaluation of clinical image quality (4). Determination of image quality in digital radiography system

International Nuclear Information System (INIS)

Katayama, Reiji

2016-01-01

Recently, for medical imaging, digital radiography systems are widely used in clinical practices. However, a study in the past reported that a patient radiation exposure level by digital radiography is in fact not lower than that by analog radiography system. High level of attention needs to be paid for over-exposure when using the conventional analog radiography with a screen and a film, as it results in high density of the film. However, for digital radiography systems, since the automatic adjusting function of image density is equipped with them, no attention for radiation dose need to be paid. Thus technologists tend to be careless and results in higher chance for over-exposure. Current digital radiography systems are high-performance in the image properties and capable of patient dose reduction. Especially, the image quality of the flat panel detector system is recognized, higher than that of the computed radiography system by imaging plates, in both objective and subjective evaluations. Therefore, we technologists are responsible for optimizing the balance between the image quality of the digital radiogram and the radiation dose required for each case. Moreover, it is also required for us as medical technologists to make effective use of such evaluation result of medical images for patients. (author)

Studies on the clinical application of MR perfusion image using arterial spin labeling method

International Nuclear Information System (INIS)

Miyasaka, Kenji

1999-01-01

A new technique for imaging brain perfusion, arterial spin labeling method was applied in clinic. Brain perfusion was imaged by FAIR and EPISTAR both of which using arterial spin labeling (ASL) method. Suitable parameters for small contamination were examined using a imaging phantom. Then normal volunteers were examined for imaging timing. Suitable time between labeling pulse and imaging pulse for brain capillary and parenchyma was 1.0 sec. For clinical application study, total 48 patients with brain diseases were examined by FAIR and/or EPISTAR. A lesion/white matter signal intensity ratio was calculated in all clinical cases. Average of signal intensity ratio in infarction, tumor and arteriovenous malformation (AVM) were 0.8, 2.2 and 18.6 at FAIR, and 0.6, 2.2 and 12.8 at EPISTAR, respectively. Low perfusion diseases such as cerebral infarction have low signal intensity ratio and high perfusion diseases such as AVM have high signal intensity ratio in both FAIR and EPISTAR. Brain lesions were imaged similarly in FAIR and EPISTAR, and no remarkable difference was found between FAIR and EPISTAR. As a result of diagnostic trial by signal intensity ratio in operated tumor, hemorrhagic cases could be diagnosed by accuracies of 75% in FAIR and 100% in EPISTAR, respectively. (author)

Giant intracranial aneurysms; Magnetic resonance imaging follow-up and clinical symptoms

Energy Technology Data Exchange (ETDEWEB)

Kondoh, Takeshi; Fujita, Katsuzo; Tamaki, Norihiko; Matsumoto, Satoshi [Kobe Univ. (Japan). School of Medicine; Yamashita, Haruo; Shirakata, Masaya

1991-06-01

Twenty-four intracranial aneurysms over 20 mm in diameter were studied with magnetic resonance (MR) imaging. MR imaging follow-up of eight cases revealed induced thrombus with homogeneous intensity and decreased size even after complete intraluminal thrombosis. Most cases demonstrated homogeneous intensity thrombus in contrast to the heterogeneous intensity of spontaneous thrombus. The clinical symptoms could not be explained retrospectively by the thrombus characteristics. Perianeurysmal high intensity, indicating cerebral edema, was detected in one case presenting with a rapid increase in size. MR imaging is useful for following these pathological intra- and perianeurysmal changes. (author).

NMR clinical imaging and spectroscopy: Its impact on nuclear medicine

International Nuclear Information System (INIS)

1990-01-01

This is a collection of four papers describing aspects of past and future use of nuclear magnetic resonance as a clinical diagnostic tool. The four papers are entitled (1) What Does NMR Offer that Nuclear Medicine Does Not? by Jerry W. Froelich, (2) Oncological Imaging: Now, Future and Impact Jerry W. Froelich, (3) Magnetic Resonance Spectroscopy/Spectroscopic Imaging and Nuclear Medicine: Past, Present and Future by H. Cecil Charles, and (4) MR Cardiology: Now, Future and Impact by Robert J. Herfkens

A comparison between clinical assessment and magnetic resonance imaging of acute hamstring injuries

NARCIS (Netherlands)

Schneider-Kolsky, Michal E.; Hoving, Jan Lucas; Warren, Price; Connell, David A.