SU-F-J-08: Quantitative SPECT Imaging of Ra-223 in a Phantom

Energy Technology Data Exchange (ETDEWEB)

Yue, J; Hobbs, R; Sgouros, G; Frey, E [Johns Hopkins University Baltimore, MD (United States)

2016-06-15

Purpose: Ra-223 therapy of prostate cancer bone metastases is being used to treat patients routinely. However, the absorbed dose distribution at the macroscopic and microscopic scales remains elusive, due to the inability to image the small activities injected. Accurate activity quantification through imaging is essential to calculate the absorbed dose in organs and sub-units in radiopharmaceutical therapy, enabling personalized absorbed dose-based treatment planning methodologies and more effective and optimal treatments. Methods: A 22 cm diameter by 20 cm long cylindrical phantom, containing a 3.52 cm diameter sphere, was used. A total of 2.01 MBq of Ra-223 was placed in the phantom with 177.6 kBq in the sphere. Images were acquired on a dual-head Siemens Symbia T16 gamma camera using three 20% full-width energy windows and centered at 84, 154, and 269 keV (120 projections, 360° rotation, 45 s per view). We have implemented reconstruction of Ra-223 SPECT projections using OS-EM (up to 20 iterations of 10 subsets) with compensation for attenuation using CT-based attenuation maps, collimator-detector response (CDR) (including septal penetration, scatter and Pb x-ray modeling), and scatter in the patient using the effective source scatter estimation (ESSE) method. The CDR functions and scatter kernels required for ESSE were computed using the SIMIND MC simulation code. All Ra-223 photon emissions as well as gamma rays from the daughters Rn-219 and Bi-211 were modeled. Results: The sensitivity of the camera in the three combined windows was 107.3 cps/MBq. The visual quality of the SPECT images was reasonably good and the activity in the sphere was 27% smaller than the true activity. This underestimation is likely due to partial volume effect. Conclusion: Absolute quantitative Ra-223 SPECT imaging is achievable with careful attention to compensate for image degrading factors and system calibration.

Sci—Thur PM: Imaging — 05: Calibration of a SPECT/CT camera for quantitative SPECT with 99mTc

International Nuclear Information System (INIS)

Gaudin, Émilie; Montégiani, Jean-François; Després, Philippe; Beauregard, Jean-Mathieu

2014-01-01

While quantitation is the norm in PET, it is not widely available yet in SPECT. This work's aim was to calibrate a commercially available SPECT/CT system to perform quantitative SPECT. Counting sensitivity, dead-time (DT) constant and partial volume effect (PVE) of the system were assessed. A dual-head Siemens SymbiaT6 SPECT/CT camera equipped with low energy high-resolution collimators was studied. 99m Tc was the radioisotope of interest because of its wide usage in nuclear medicine. First, point source acquisitions were performed (activity: 30–990MBq). Further acquisitions were then performed with a uniform Jaszczak phantom filled with water at high activity (25–5000MBq). PVE was studied using 6 hot spheres (diameters: 9.9–31.2 mm) filled with 99m Tc (2.8MBq/cc) in the Jaszczak phantom, which was: (1) empty, (2) water-filled and (3) water-filled with low activity (0.1MBq/cc). The data was reconstructed with the Siemens's Flash3D iterative algorithm with 4 subsets and 8 iterations, attenuation-correction (AC) and scatter-correction (SC). DT modelling was based on the total spectrum counting rate. Sensitivity was assessed using AC-SC reconstructed SPECT data. Sensitivity and DT for the sources were 99.51±1.46cps/MBq and 0.60±0.04µs. For the phantom, sensitivity and DT were 109.9±2.3cps/MBq and 0.62±0.13µs. The recovery-coefficient varied from 5% for the 9.9mm, to 80% for the 31.2mm spheres. With our calibration methods, both sensitivity and DT constant of the SPECT camera had little dependence on the object geometry and attenuation. For small objects of known size, recovery-coefficient can be applied to correct PVE. Clinical quantitative SPECT appears to be possible and has many potential applications

Novel SPECT Technologies and Approaches in Cardiac Imaging

Directory of Open Access Journals (Sweden)

Piotr Slomka

2016-12-01

Full Text Available Recent novel approaches in myocardial perfusion single photon emission CT (SPECT have been facilitated by new dedicated high-efficiency hardware with solid-state detectors and optimized collimators. New protocols include very low-dose (1 mSv stress-only, two-position imaging to mitigate attenuation artifacts, and simultaneous dual-isotope imaging. Attenuation correction can be performed by specialized low-dose systems or by previously obtained CT coronary calcium scans. Hybrid protocols using CT angiography have been proposed. Image quality improvements have been demonstrated by novel reconstructions and motion correction. Fast SPECT acquisition facilitates dynamic flow and early function measurements. Image processing algorithms have become automated with virtually unsupervised extraction of quantitative imaging variables. This automation facilitates integration with clinical variables derived by machine learning to predict patient outcome or diagnosis. In this review, we describe new imaging protocols made possible by the new hardware developments. We also discuss several novel software approaches for the quantification and interpretation of myocardial perfusion SPECT scans.

The additive prognostic value of perfusion and functional data assessed by quantitative gated SPECT in women

NARCIS (Netherlands)

Y.G.C.J. America (Yves); J.J. Bax (Jeroen); H. Boersma (Eric); M. Stokkel (Marcel); E.E. van der Wall (Ernst)

2009-01-01

textabstractBackground: The aim of this study was to assess the prognostic value of technetium-99m tetrofosmin gated SPECT imaging in women using quantitative gated single photon emission computed tomography (SPECT) imaging. Methods: We followed 453 consecutive female patients. Average follow-up was

Global scaling for semi-quantitative analysis in FP-CIT SPECT.

Science.gov (United States)

Kupitz, D; Apostolova, I; Lange, C; Ulrich, G; Amthauer, H; Brenner, W; Buchert, R

2014-01-01

Semi-quantitative characterization of dopamine transporter availability from single photon emission computed tomography (SPECT) with 123I-ioflupane (FP-CIT) is based on uptake ratios relative to a reference region. The aim of this study was to evaluate the whole brain as reference region for semi-quantitative analysis of FP-CIT SPECT. The rationale was that this might reduce statistical noise associated with the estimation of non-displaceable FP-CIT uptake. 150 FP-CIT SPECTs were categorized as neurodegenerative or non-neurodegenerative by an expert. Semi-quantitative analysis of specific binding ratios (SBR) was performed with a custom-made tool based on the Statistical Parametric Mapping software package using predefined regions of interest (ROIs) in the anatomical space of the Montreal Neurological Institute. The following reference regions were compared: predefined ROIs for frontal and occipital lobe and whole brain (without striata, thalamus and brainstem). Tracer uptake in the reference region was characterized by the mean, median or 75th percentile of its voxel intensities. The area (AUC) under the receiver operating characteristic curve was used as performance measure. The highest AUC of 0.973 was achieved by the SBR of the putamen with the 75th percentile in the whole brain as reference. The lowest AUC for the putamen SBR of 0.937 was obtained with the mean in the frontal lobe as reference. We recommend the 75th percentile in the whole brain as reference for semi-quantitative analysis in FP-CIT SPECT. This combination provided the best agreement of the semi-quantitative analysis with visual evaluation of the SPECT images by an expert and, therefore, is appropriate to support less experienced physicians.

Evaluation of Tl-201 SPECT imaging findings in prostate cancer

Directory of Open Access Journals (Sweden)

Sinem Ozyurt

2015-07-01

Full Text Available Objectives: To compare with histopathological findings the findings of prostate cancer imaging by SPECT method using Tl-201 as a tumor seeking agent. Methods: The study comprised 59 patients (age range 51-79 years, mean age 65.3 ± 6.8 years who were planned to have transrectal ultrasonography (TRUS-guided biopsies due to suspicion of prostate cancer between April 2011 and September 2011. Early planar, late planar and SPECT images were obtained for all patients. Scintigraphic evaluation was made in relation to uptake presence and patterns in the visual assessment and to Tumor/Background (T/Bg ratios for both planar and SPECT images in the quantitative assessment. Histopathological findings were compatible with benign etiology in 36 (61% patients and malign etiology in 23 (39% patients. Additionally, comparisons were made to evaluate the relationships between uptake patterns,total PSA values and Gleason scores. Results: A statistically significant difference was found between the benign and malignant groups in terms of uptake in planar and SPECT images and T/Bg ratios and PSA values. No statistically significant difference was found between uptake patterns of planar and SPECT images and Gleason scores in the malignant group. Conclusions: SPECT images were superior to planar images in the comparative assessment. Tl-201 SPECT imaging can provide an additional contribution to clinical practice in the diagnosis of prostate cancer and it can be used in selected patients.

Quantitative organ visualization using SPECT

International Nuclear Information System (INIS)

Kircos, L.T.; Carey, J.E. Jr.; Keyes, J.W. Jr.

1987-01-01

Quantitative organ visualization (QOV) was performed using single photon emission computed tomography (SPECT). Organ size was calculated from serial, contiguous ECT images taken through the organ of interest with image boundaries determined using a maximum directional gradient edge finding technique. Organ activity was calculated using ECT counts bounded by the directional gradient, imaging system efficiency, and imaging time. The technique used to perform QOV was evaluated using phantom studies, in vivo canine liver, spleen, bladder, and kidney studies, and in vivo human bladder studies. It was demonstrated that absolute organ activity and organ size could be determined with this system and total imaging time restricted to less than 45 min to an accuracy of about +/- 10% providing the minimum dimensions of the organ are greater than the FWHM of the imaging system and the total radioactivity within the organ of interest exceeds 15 nCi/cc for dog-sized torsos. In addition, effective half-lives of approximately 1.5 hr or greater could be determined

SPECT imaging of cardiac reporter gene expression in living rabbits

International Nuclear Information System (INIS)

Liu Ying; Lan Xiaoli; Zhang Liang; Wu Tao; Jiang Rifeng; Zhang Yongxue

2009-01-01

This work is to demonstrate feasibility of imaging the expression of herpes simplex virus 1-thymidine kinase (HSVI-tk) reporter gene in rabbits myocardium by using the reporter probe 131 I-2'-fluoro-2'-deoxy-l-β-D-arabinofuranosyl-5-iodouracil ( 131 I-FIAU) and SPECT. Rabbits of the study group received intramyocardial injection of Ad5-tk and control group received aseptic saline injection. Two sets of experiments were performed on the study group. Rabbits of the 1st set were injected with 131 I-FIAU 600 μCi at Day 2 after intramyocardial transfection of Ad5-tk in 1xl0 9 , 5x10 8 , 1x10 8 , 5x10 7 and 1x10 7 pfu, and heart SPECT imaging was done at different hours. Rabbits of the 2nd were transferred various titers of Ad5-tk (1x10 9 , 5x10 8 , 1x10 8 , 5x10 7 , 1x10 7 pfu) to determine the threshold and optimal viral titer needed for detection of gene expression. Two days later, 131 I-FIAU was injected and heart SPECT imaging was performed at 6, 24 and 48 h, before killing them for gamma counting of the hearts. Reverse transcription-polymerase chain reaction (RT-PCR) was used to verify the transferred HSVI-tk gene expression. Semi-quantitative analysis derived of region of interest (ROI) of SPECT images and RT-PCR images was performed and the relationship of SPECT images with ex vivo gamma counting and mRNA level were evaluated. SPECT images conformed 131 I-FIAU accumulation in rabbits injected with Ad5-tk in the anterolateral wall. The optimal images quality was obtained at 24-48 h for different viral titers. The highest radioactivity in the focal myocardium was seen at 6 h, and then declined with time. The threshold was 5x10 7 pfu of virus titer. The result could be set better in 1-5x10 8 pfu by SPECT analysis and gamma counting. ROI-derived semi-quantitative study on SPECT images correlated well with ex vivo gamma counting and mRNA levels from RT-PCR analysis. The HSVI-tk/ 131 I-FIAU reporter gene/reporter probe system is feasible for cardiac SPECT reporter

SPECT myocardial blood flow quantitation toward clinical use: a comparative study with {sup 13}N-Ammonia PET myocardial blood flow quantitation

Energy Technology Data Exchange (ETDEWEB)

Hsu, Bailing [University of Missouri-Columbia, Nuclear Science and Engineering Institute, Columbia, Missouri (United States); Hu, Lien-Hsin; Yang, Bang-Hung; Ting, Chien-Hsin; Huang, Wen-Sheng [Taipei Veterans General Hospital, Department of Nuclear Medicine, Taipei (China); Chen, Lung-Ching [Shin Kong Wu-Ho Su Memorial Hospital, Division of Cardiology, Taipei (China); Chen, Yen-Kung [Shin Kong Wu-Ho Su Memorial Hospital, Department of Nuclear Medicine, Taipei (China); Hung, Guang-Uei [Chang Bing Show Chwan Memorial Hospital, Department of Nuclear Medicine, Changhua (China); Wu, Tao-Cheng [National Yang-Ming University, Cardiovascular Research Center, Taipei (China)

2017-01-15

The aim of this study was to evaluate the accuracy of myocardial blood flow (MBF) quantitation of {sup 99m}Tc-Sestamibi (MIBI) single photon emission computed tomography (SPECT) compared with {sup 13}N-Ammonia (NH3) position emission tomography (PET) on the same cohorts. Recent advances of SPECT technologies have been applied to develop MBF quantitation as a promising tool to diagnose coronary artery disease (CAD) for areas where PET MBF quantitation is not available. However, whether the SPECT approach can achieve the same level of accuracy as the PET approach for clinical use still needs further investigations. Twelve healthy volunteers (HVT) and 16 clinical patients with CAD received both MIBI SPECT and NH3 PET flow scans. Dynamic SPECT images acquired with high temporary resolution were fully corrected for physical factors and processed to quantify K1 using the standard compartmental modeling. Human MIBI tracer extraction fraction (EF) was determined by comparing MIBI K1 and NH3 flow on the HVT group and then used to convert flow values from K1 for all subjects. MIBI and NH3 flow values were systematically compared to validate the SPECT approach. The human MIBI EF was determined as [1.0-0.816*exp(-0.267/MBF)]. Global and regional MBF and myocardial flow reserve (MFR) of MIBI SPECT and NH3 PET were highly correlated for all subjects (global R{sup 2}: MBF = 0.92, MFR = 0.78; regional R{sup 2}: MBF ≥ 0.88, MFR ≥ 0.71). No significant differences for rest flow, stress flow, and MFR between these two approaches were observed (All p ≥ 0.088). Bland-Altman plots overall revealed small bias between MIBI SPECT and NH3 PET (global: ΔMBF = -0.03Lml/min/g, ΔMFR = 0.07; regional: ΔMBF = -0.07 - 0.06, ΔMFR = -0.02 - 0.22). Quantitation with SPECT technologies can be accurate to measure myocardial blood flow as PET quantitation while comprehensive imaging factors of SPECT to derive the variability between these two approaches were fully addressed and corrected

SPECT myocardial blood flow quantitation toward clinical use: a comparative study with "1"3N-Ammonia PET myocardial blood flow quantitation

International Nuclear Information System (INIS)

Hsu, Bailing; Hu, Lien-Hsin; Yang, Bang-Hung; Ting, Chien-Hsin; Huang, Wen-Sheng; Chen, Lung-Ching; Chen, Yen-Kung; Hung, Guang-Uei; Wu, Tao-Cheng

2017-01-01

The aim of this study was to evaluate the accuracy of myocardial blood flow (MBF) quantitation of "9"9"mTc-Sestamibi (MIBI) single photon emission computed tomography (SPECT) compared with "1"3N-Ammonia (NH3) position emission tomography (PET) on the same cohorts. Recent advances of SPECT technologies have been applied to develop MBF quantitation as a promising tool to diagnose coronary artery disease (CAD) for areas where PET MBF quantitation is not available. However, whether the SPECT approach can achieve the same level of accuracy as the PET approach for clinical use still needs further investigations. Twelve healthy volunteers (HVT) and 16 clinical patients with CAD received both MIBI SPECT and NH3 PET flow scans. Dynamic SPECT images acquired with high temporary resolution were fully corrected for physical factors and processed to quantify K1 using the standard compartmental modeling. Human MIBI tracer extraction fraction (EF) was determined by comparing MIBI K1 and NH3 flow on the HVT group and then used to convert flow values from K1 for all subjects. MIBI and NH3 flow values were systematically compared to validate the SPECT approach. The human MIBI EF was determined as [1.0-0.816*exp(-0.267/MBF)]. Global and regional MBF and myocardial flow reserve (MFR) of MIBI SPECT and NH3 PET were highly correlated for all subjects (global R"2: MBF = 0.92, MFR = 0.78; regional R"2: MBF ≥ 0.88, MFR ≥ 0.71). No significant differences for rest flow, stress flow, and MFR between these two approaches were observed (All p ≥ 0.088). Bland-Altman plots overall revealed small bias between MIBI SPECT and NH3 PET (global: ΔMBF = -0.03Lml/min/g, ΔMFR = 0.07; regional: ΔMBF = -0.07 - 0.06, ΔMFR = -0.02 - 0.22). Quantitation with SPECT technologies can be accurate to measure myocardial blood flow as PET quantitation while comprehensive imaging factors of SPECT to derive the variability between these two approaches were fully addressed and corrected. (orig.)

Distributed 3-D iterative reconstruction for quantitative SPECT

International Nuclear Information System (INIS)

Ju, Z.W.; Frey, E.C.; Tsui, B.M.W.

1995-01-01

The authors describe a distributed three dimensional (3-D) iterative reconstruction library for quantitative single-photon emission computed tomography (SPECT). This library includes 3-D projector-backprojector pairs (PBPs) and distributed 3-D iterative reconstruction algorithms. The 3-D PBPs accurately and efficiently model various combinations of the image degrading factors including attenuation, detector response and scatter response. These PBPs were validated by comparing projection data computed using the projectors with that from direct Monte Carlo (MC) simulations. The distributed 3-D iterative algorithms spread the projection-backprojection operations for all the projection angles over a heterogeneous network of single or multi-processor computers to reduce the reconstruction time. Based on a master/slave paradigm, these distributed algorithms provide dynamic load balancing and fault tolerance. The distributed algorithms were verified by comparing images reconstructed using both the distributed and non-distributed algorithms. Computation times for distributed 3-D reconstructions running on up to 4 identical processors were reduced by a factor approximately 80--90% times the number of the processors participating, compared to those for non-distributed 3-D reconstructions running on a single processor. When combined with faster affordable computers, this library provides an efficient means for implementing accurate reconstruction and compensation methods to improve quality and quantitative accuracy in SPECT images

Quantitative SPECT reconstruction of iodine-123 data

International Nuclear Information System (INIS)

Gilland, D.R.; Jaszczak, R.J.; Greer, K.L.; Coleman, R.E.

1991-01-01

Many clinical and research studies in nuclear medicine require quantitation of iodine-123 ( 123 I) distribution for the determination of kinetics or localization. The objective of this study was to implement several reconstruction methods designed for single-photon emission computed tomography (SPECT) using 123 I and to evaluate their performance in terms of quantitative accuracy, image artifacts, and noise. The methods consisted of four attenuation and scatter compensation schemes incorporated into both the filtered backprojection/Chang (FBP) and maximum likelihood-expectation maximization (ML-EM) reconstruction algorithms. The methods were evaluated on data acquired of a phantom containing a hot sphere of 123 I activity in a lower level background 123 I distribution and nonuniform density media. For both reconstruction algorithms, nonuniform attenuation compensation combined with either scatter subtraction or Metz filtering produced images that were quantitatively accurate to within 15% of the true value. The ML-EM algorithm demonstrated quantitative accuracy comparable to FBP and smaller relative noise magnitude for all compensation schemes

Quantitative accuracy of serotonergic neurotransmission imaging with high-resolution 123I SPECT

International Nuclear Information System (INIS)

Kuikka, J.T.

2004-01-01

Aim: Serotonin transporter (SERT) imaging can be used to study the role of regional abnormalities of neurotransmitter release in various mental disorders and to study the mechanism of action of therapeutic drugs or drugs' abuse. We examine the quantitative accuracy and reproducibility that can be achieved with high-resolution SPECT of serotonergic neurotransmission. Method: Binding potential (BP) of 123 I labeled tracer specific for midbrain SERT was assessed in 20 healthy persons. The effects of scatter, attenuation, partial volume, misregistration and statistical noise were estimated using phantom and human studies. Results: Without any correction, BP was underestimated by 73%. The partial volume error was the major component in this underestimation whereas the most critical error for the reproducibility was misplacement of region of interest (ROI). Conclusion: The proper ROI registration, the use of the multiple head gamma camera with transmission based scatter correction introduce more relevant results. However, due to the small dimensions of the midbrain SERT structures and poor spatial resolution of SPECT, the improvement without the partial volume correction is not great enough to restore the estimate of BP to that of the true one. (orig.) [de

Molecular imaging agents for SPECT (and SPECT/CT)

International Nuclear Information System (INIS)

Gnanasegaran, Gopinath; Ballinger, James R.

2014-01-01

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

Molecular imaging agents for SPECT (and SPECT/CT)

Energy Technology Data Exchange (ETDEWEB)

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

2014-05-15

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

Diagnostic evaluation of brain SPECT imaging in diseases of nervous system

Energy Technology Data Exchange (ETDEWEB)

Yongsheng, Jiang; Chengmo, Zhu; Jixian, Zhang; Weijia, Tian [Shanghai Second Medical Univ. (China). Ruijing Hospital

1992-11-01

The dynamic distributions of home made ECD and the Amersham brain SPECT imaging agent 'Ceretec' in normal person as well as their diagnostic use in diseases of nervous system were investigated. Semi-quantitative analysis combined with direct observation was more accurate for the diagnosis. Aside from cerebrovascular diseases, SPECT brain imaging has its unique value for the diagnosis of transient ischemic attack, Alzheimer disease, multiple ischemic dementia and epilepsy etc.

A new dynamic myocardial phantom for evaluation of SPECT and PET quantitation in systolic and diastolic conditions

International Nuclear Information System (INIS)

Dreuille, O. de; Bendriem, B.; Riddell, C.

1996-01-01

We present a new dynamic myocardial phantom designed to evaluate SPECT and PET imaging in systolic and diastolic conditions. The phantom includes a thoracic attenuating media and the myocardial wall thickness varying during the scan can be performed. In this study the phantom was used with three different wall thickness characteristic of a systolic, end-diastolic and pathologic end-diastolic condition. The myocardium was filled with 99m Tc, 18 F and Gd and imaged by SPECT, PET and MRI. SPECT attenuation correction was performed using a modified PET transmission. A bull's eyes image was obtained for all data and wall ROI were then drawn for analysis. Using MRI as a reference, error from PET, SPECT and attenuation corrected SPECT were calculated. Systolic PET performances agree with MRI. Quantitation loss due to wall thickness reduction compared to the systole. Attenuation correction in SPECT leads to significant decrease of the error both in systole (from 29% to 14%) and diastole (35% to 22%). This is particularly sensitive for septum and inferior walls. SPECT residual errors (14% in systole and 22% in pathologic end-diastole) are likely caused by scatter, noise and depth dependent resolution effect. The results obtained with this dynamical phantom demonstrate the quantitation improvement achieved in SPECT with attenuation correction and also reinforce the need for variable resolution correction in addition to attenuation correction

Improvement of quantitation in SPECT: Attenuation and scatter correction using non-uniform attenuation data

International Nuclear Information System (INIS)

Mukai, T.; Torizuka, K.; Douglass, K.H.; Wagner, H.N.

1985-01-01

Quantitative assessment of tracer distribution with single photon emission computed tomography (SPECT) is difficult because of attenuation and scattering of gamma rays within the object. A method considering the source geometry was developed, and effects of attenuation and scatter on SPECT quantitation were studied using phantoms with non-uniform attenuation. The distribution of attenuation coefficients (μ) within the source were obtained by transmission CT. The attenuation correction was performed by an iterative reprojection technique. The scatter correction was done by convolution of the attenuation corrected image and an appropriate filter made by line source studies. The filter characteristics depended on μ and SPEC measurement at each pixel. The SPECT obtained by this method showed the most reasonable results than the images reconstructed by other methods. The scatter correction could compensate completely for a 28% scatter components from a long line source, and a 61% component for thick and extended source. Consideration of source geometries was necessary for effective corrections. The present method is expected to be valuable for the quantitative assessment of regional tracer activity

Quality control of analogue to digital conversion circuitry for artefact-free SPECT imaging

International Nuclear Information System (INIS)

Gillen, G.J.; Elliott, A.T.

1992-01-01

A simple method for the objective, quantitative assessment of analogue to digital conversion (ADC) differential linearity has been developed for SPECT imaging. The analytical approach uses the fact that a differential non-linearity in the ADC will produce a non-uniformity in the digitized image which has a well defined periodicity. This can be most clearly demonstrated in the frequency space domain by determining the Fourier transform of a thick profile which is taken through the centre of a flood field image. The accuracy of the method permits deteriorations in the performance of ADCs to be detected well before significant reductions in SPECT image quality are produced. The availability of a quantitative measure of ADC performance, which can be tested objectively using a simple data acquisition method, is of value in the specification, acceptance testing and general quality control of gamma camera SPECT systems. (author)

Multi-centre evaluation of accuracy and reproducibility of planar and SPECT image quantification. An IAEA phantom study

Energy Technology Data Exchange (ETDEWEB)

Zimmermann, Brian E. [National Institute of Standards and Technology, Gaithersburg, MD (United States); Grosev, Darko [Univ. Hospital Centre Zagreb (Croatia); Buvat, Irene [Service Hospitalier Frederic Joliot, Paris (France); and others

2017-08-01

Accurate quantitation of activity provides the basis for internal dosimetry of targeted radionuclide therapies. This study investigated quantitative imaging capabilities at sites with a variety of experience and equipment and assessed levels of errors in activity quantitation in Single-Photon Emission Computed Tomography (SPECT) and planar imaging. Participants from 9 countries took part in a comparison in which planar, SPECT and SPECT with X ray computed tomography (SPECT-CT) imaging were used to quantify activities of four epoxy-filled cylinders containing {sup 133}Ba, which was chosen as a surrogate for {sup 131}I. The sources, with nominal volumes of 2, 4, 6 and 23 mL, were calibrated for {sup 133}Ba activity by the National Institute of Standards and Technology, but the activity was initially unknown to the participants. Imaging was performed in a cylindrical phantom filled with water. Two trials were carried out in which the participants first estimated the activities using their local standard protocols, and then repeated the measurements using a standardized acquisition and analysis protocol. Finally, processing of the imaging data from the second trial was repeated by a single centre using a fixed protocol. In the first trial, the activities were underestimated by about 15% with planar imaging. SPECT with Chang's first order attenuation correction (Chang-AC) and SPECT-CT overestimated the activity by about 10%. The second trial showed moderate improvements in accuracy and variability. Planar imaging was subject to methodological errors, e.g., in the use of a transmission scan for attenuation correction. The use of Chang-AC was subject to variability from the definition of phantom contours. The project demonstrated the need for training and standardized protocols to achieve good levels of quantitative accuracy and precision in a multicentre setting. Absolute quantification of simple objects with no background was possible with the strictest protocol to

Quantitation of cerebral blood volume by 99mTc-DTPA-HSA SPECT

International Nuclear Information System (INIS)

Inoue, Yusuke; Machida, Kikuo; Momose, Toshimitsu

1992-01-01

The characteristics of technetium-99m diethylenetriaminepentaacetic acid human serum albumin ( 99m Tc-DTPA-HSA) as an agent for quantitation of cerebral blood volume (CBV) were examined. The radioactivity after decay correction as a percentage of the activity at 10 minutes was 84.3±1.3% at 120 minutes after the injection of 99m Tc-DTPA-HSA. Radioactivity was found exclusively in plasma, with little in blood cells. The blood retention of 99m Tc-DTPA-HSA is sufficient, and its use in the quantitation of CBV omits the need for centrifugation of the blood sample. CBV quantified using the tracer and a SPECT system with a single-head rotating gamma camera was 4.09±0.60 ml/100g brain, similar to values reported previously. Two serial SPECT scans provided similar images, and the CBV values determined by the two scans were closely correlated (p 99m Tc-DTPA-HSA has useful properties for quantitative CBV measurement and that quantitation of CBV by 99m Tc-DTPA-HSA SPECT is feasible using a system with a single-head rotating gamma camera. (author)

The characteristics of SPECT images in childhood benign partial epilepsy

International Nuclear Information System (INIS)

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

1998-01-01

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

SPECT and 3D display quantitative evaluation in renal DMSA scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Lyra, M; Skouroliakou, K; Emmanouilides, I; Stratis, I [Univerisity of Athens, Department of Radiology and Department of Mathematics, Athens (Greece)

1999-12-31

The evaluation of cortical damage to the kidneys, especially in children, is currently performed by means of Tc99m-DMSA renal scan. The routine involves the acquisition of planar images and their qualitative and quantitative evaluation. Many studies have dealt with the possible advantage that SPECT could possess on qualitative criteria. This study attempts to quantitatively deal with the issue by the calculation of an index. The results exhibit a clear advantage of tomographic and 3D reconstructed images over the conventional planar ones. (authors) 14 refs., 3 figs., 1 tabs.

Comparison of conventional, model-based quantitative planar, and quantitative SPECT image processing methods for organ activity estimation using In-111 agents

International Nuclear Information System (INIS)

He, Bin; Frey, Eric C

2006-01-01

Accurate quantification of organ radionuclide uptake is important for patient-specific dosimetry. The quantitative accuracy from conventional conjugate view methods is limited by overlap of projections from different organs and background activity, and attenuation and scatter. In this work, we propose and validate a quantitative planar (QPlanar) processing method based on maximum likelihood (ML) estimation of organ activities using 3D organ VOIs and a projector that models the image degrading effects. Both a physical phantom experiment and Monte Carlo simulation (MCS) studies were used to evaluate the new method. In these studies, the accuracies and precisions of organ activity estimates for the QPlanar method were compared with those from conventional planar (CPlanar) processing methods with various corrections for scatter, attenuation and organ overlap, and a quantitative SPECT (QSPECT) processing method. Experimental planar and SPECT projections and registered CT data from an RSD Torso phantom were obtained using a GE Millenium VH/Hawkeye system. The MCS data were obtained from the 3D NCAT phantom with organ activity distributions that modelled the uptake of 111 In ibritumomab tiuxetan. The simulations were performed using parameters appropriate for the same system used in the RSD torso phantom experiment. The organ activity estimates obtained from the CPlanar, QPlanar and QSPECT methods from both experiments were compared. From the results of the MCS experiment, even with ideal organ overlap correction and background subtraction, CPlanar methods provided limited quantitative accuracy. The QPlanar method with accurate modelling of the physical factors increased the quantitative accuracy at the cost of requiring estimates of the organ VOIs in 3D. The accuracy of QPlanar approached that of QSPECT, but required much less acquisition and computation time. Similar results were obtained from the physical phantom experiment. We conclude that the QPlanar method, based

Monte Carlo simulation of PET and SPECT imaging of {sup 90}Y

Energy Technology Data Exchange (ETDEWEB)

Takahashi, Akihiko, E-mail: takahsr@hs.med.kyushu-u.ac.jp; Sasaki, Masayuki [Department of Health Sciences, Faculty of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Himuro, Kazuhiko; Yamashita, Yasuo; Komiya, Isao [Division of Radiology, Department of Medical Technology, Kyushu University Hospital, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Baba, Shingo [Department of Clinical Radiology, Kyushu University Hospital, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan)

2015-04-15

Purpose: Yittrium-90 ({sup 90}Y) is traditionally thought of as a pure beta emitter, and is used in targeted radionuclide therapy, with imaging performed using bremsstrahlung single-photon emission computed tomography (SPECT). However, because {sup 90}Y also emits positrons through internal pair production with a very small branching ratio, positron emission tomography (PET) imaging is also available. Because of the insufficient image quality of {sup 90}Y bremsstrahlung SPECT, PET imaging has been suggested as an alternative. In this paper, the authors present the Monte Carlo-based simulation–reconstruction framework for {sup 90}Y to comprehensively analyze the PET and SPECT imaging techniques and to quantitatively consider the disadvantages associated with them. Methods: Our PET and SPECT simulation modules were developed using Monte Carlo simulation of Electrons and Photons (MCEP), developed by Dr. S. Uehara. PET code (MCEP-PET) generates a sinogram, and reconstructs the tomography image using a time-of-flight ordered subset expectation maximization (TOF-OSEM) algorithm with attenuation compensation. To evaluate MCEP-PET, simulated results of {sup 18}F PET imaging were compared with the experimental results. The results confirmed that MCEP-PET can simulate the experimental results very well. The SPECT code (MCEP-SPECT) models the collimator and NaI detector system, and generates the projection images and projection data. To save the computational time, the authors adopt the prerecorded {sup 90}Y bremsstrahlung photon data calculated by MCEP. The projection data are also reconstructed using the OSEM algorithm. The authors simulated PET and SPECT images of a water phantom containing six hot spheres filled with different concentrations of {sup 90}Y without background activity. The amount of activity was 163 MBq, with an acquisition time of 40 min. Results: The simulated {sup 90}Y-PET image accurately simulated the experimental results. PET image is visually

SP-ECT imaging and its physical study

International Nuclear Information System (INIS)

Kinoshita, Fujimi

1983-01-01

Recently, more than a hundred hospitals are provided with SPECT system for clinical examination in Japan. However, a standardization of measuring method and performance test of the systems is ont yet made. We have been studying some basic problems of SPECT system with special phantoms originaly designed by ourselves. We got a conclusion that a standardized phantom is necessary for comparing performances between SPECT systems. In clinical experiences with 3,332 cases, we think that SPECT image combined with conventional image presents much more informations for accurate diagnosis, especially in brain, bone and tumor imagings. Synthesized image of SPECT and XCT, double tracer image and transmission image are useful to visualize the body contour and the clinical diagnosis. (author)

SPECT and PET imaging in epilepsy

International Nuclear Information System (INIS)

Semah, F.

2007-01-01

Positron emission tomography (PET) and single photon emission computed tomography (SPECT) imaging are very useful for the management of patients with medically refractory partial epilepsy. Presurgical evaluation of patients with medically refractory partial epilepsy often included PET imaging using FDG. The use of SPECT in these patients adds some more information and gives the clinicians the possibility of having ictal imaging. Furthermore, PET and SPECT imaging are performed to better understand the pathophysiology of epilepsy. (authors)

Nuclear myocardial perfusion imaging using thallium-201 with a novel multifocal collimator SPECT/CT: IQ-SPECT versus conventional protocols in normal subjects.

Science.gov (United States)

Matsuo, Shinro; Nakajima, Kenichi; Onoguchi, Masahisa; Wakabayash, Hiroshi; Okuda, Koichi; Kinuya, Seigo

2015-06-01

A novel multifocal collimator, IQ-SPECT (Siemens) consists of SMARTZOOM, cardio-centric and 3D iterative SPECT reconstruction and makes it possible to perform MPI scans in a short time. The aims are to delineate the normal uptake in thallium-201 ((201)Tl) SPECT in each acquisition method and to compare the distribution between new and conventional protocol, especially in patients with normal imaging. Forty patients (eight women, mean age of 75 years) who underwent myocardial perfusion imaging were included in the study. All patients underwent one-day protocol perfusion scan after an adenosine-stress test and at rest after administering (201)Tl and showed normal results. Acquisition was performed on a Symbia T6 equipped with a conventional dual-headed gamma camera system (Siemens ECAM) and with a multifocal SMARTZOOM collimator. Imaging was performed with a conventional system followed by IQ-SPECT/computed tomography (CT). Reconstruction was performed with or without X-ray CT-derived attenuation correction (AC). Two nuclear physicians blinded to clinical information interpreted all myocardial perfusion images. A semi-quantitative myocardial perfusion was analyzed by a 17-segment model with a 5-point visual scoring. The uptake of each segment was measured and left ventricular functions were analyzed by QPS software. IQ-SPECT provided good or excellent image quality. The quality of IQ-SPECT images without AC was similar to those of conventional LEHR study. Mid-inferior defect score (0.3 ± 0.5) in the conventional LEHR study was increased significantly in IQ-SPECT with AC (0 ± 0). IQ-SPECT with AC improved the mid-inferior decreased perfusion shown in conventional images. The apical tracer count in IQ-SPECT with AC was decreased compared to that in LEHR (0.1 ± 0.3 vs. 0.5 ± 0.7, p IQ-SPECT was significantly higher than that from the LEHR collimator (p = 0.0009). The images of IQ-SPECT acquired in a short time are equivalent to that of conventional LEHR

Brain spect imaging

International Nuclear Information System (INIS)

Lee, R.G.L.; Hill, T.C.; Holman, B.L.

1989-01-01

This paper discusses how the rapid development of single-photon radiopharmaceuticals has given new life to tomographic brain imaging in nuclear medicine. Further developments in radiopharmaceuticals and refinements in neuro-SPECT (single-photon emission computed tomography) instrumentation should help to reinstate brain scintigraphy as an important part of neurologic diagnosis. SPECT of the brain evolved from experimentation using prototype instrumentation during the early 1960s. Although tomographic studies provided superior diagnostic accuracy when compared to planar techniques, the arrival of X-ray CT of the head resulted in the rapid demise of technetium brain imaging

Ventilation/perfusion SPECT or SPECT/CT for lung function imaging in patients with pulmonary emphysema?

Science.gov (United States)

Froeling, Vera; Heimann, Uwe; Huebner, Ralf-Harto; Kroencke, Thomas J; Maurer, Martin H; Doellinger, Felix; Geisel, Dominik; Hamm, Bernd; Brenner, Winfried; Schreiter, Nils F

2015-07-01

To evaluate the utility of attenuation correction (AC) of V/P SPECT images for patients with pulmonary emphysema. Twenty-one patients (mean age 67.6 years) with pulmonary emphysema who underwent V/P SPECT/CT were included. AC/non-AC V/P SPECT images were compared visually and semiquantitatively. Visual comparison of AC/non-AC images was based on a 5-point likert scale. Semiquantitative comparison assessed absolute counts per lung (aCpLu) and lung lobe (aCpLo) for AC/non-AC images using software-based analysis; percentage counts (PC = (aCpLo/aCpLu) × 100) were calculated. Correlation between AC/non-AC V/P SPECT images was analyzed using Spearman's rho correlation coefficient; differences were tested for significance with the Wilcoxon rank sum test. Visual analysis revealed high conformity for AC and non-AC V/P SPECT images. Semiquantitative analysis of PC in AC/non-AC images had an excellent correlation and showed no significant differences in perfusion (ρ = 0.986) or ventilation (ρ = 0.979, p = 0.809) SPECT/CT images. AC of V/P SPECT images for lung lobe-based function imaging in patients with pulmonary emphysema do not improve visual or semiquantitative image analysis.

Quantitative estimation of myocardial thickness by the wall thickness map with Tl-201 myocardial SPECT and its clinical use

International Nuclear Information System (INIS)

Sekiai, Yasuhiro; Sawai, Michihiko; Murayama, Susumu

1988-01-01

To estimate the wall thickness of left ventricular myocardium objectively and quantitatively, we adopted the device of wall thickness map (WTM) with Tl-201 myocardial SPECT. For validation on measuring left ventricular wall thickness with SPECT, fundamental studies were carried out with phantom models, and clinical studies were performed in 10 cases comparing the results from SPECT with those in echocardiography. To draw the WTM, left ventricular wall thickness was measured using the cut off method from SPECT images obtained at 5.6 mm intervals from the base and middle of left ventricle: short-axis image for the base and middle of left ventricle and vertical and horizontal long-axis images for the apical region. Wall thickness was defined from the number of pixel above the cut off level. Results of fundamental studies disclosed that it is impossible to evaluate the thickness of less than 10 mm by Tl-201 myocardial SPECT but possible to discriminate wall thickness of 10 mm, 15 mm, and 20 mm by Tl-201 myocardial SPECT. Echocardiographic results supported the validity of WTM, showing a good linear correlation (r = 0.96) between two methods on measuring wall thickness of left ventricle. We conclude that the WTM applied in this report may be useful for objective and quantitative estimation of myocardial hypertrophy. (author)

A methodology for generating normal and pathological brain perfusion SPECT images for evaluation of MRI/SPECT fusion methods: application in epilepsy

Energy Technology Data Exchange (ETDEWEB)

Grova, C [Laboratoire IDM, Faculte de Medecine, Universite de Rennes 1, Rennes (France); Jannin, P [Laboratoire IDM, Faculte de Medecine, Universite de Rennes 1, Rennes (France); Biraben, A [Laboratoire IDM, Faculte de Medecine, Universite de Rennes 1, Rennes (France); Buvat, I [INSERM U494, CHU Pitie Salpetriere, Paris (France); Benali, H [INSERM U494, CHU Pitie Salpetriere, Paris (France); Bernard, A M [Service de Medecine Nucleaire, Centre Eugene Marquis, Rennes (France); Scarabin, J M [Laboratoire IDM, Faculte de Medecine, Universite de Rennes 1, Rennes (France); Gibaud, B [Laboratoire IDM, Faculte de Medecine, Universite de Rennes 1, Rennes (France)

2003-12-21

Quantitative evaluation of brain MRI/SPECT fusion methods for normal and in particular pathological datasets is difficult, due to the frequent lack of relevant ground truth. We propose a methodology to generate MRI and SPECT datasets dedicated to the evaluation of MRI/SPECT fusion methods and illustrate the method when dealing with ictal SPECT. The method consists in generating normal or pathological SPECT data perfectly aligned with a high-resolution 3D T1-weighted MRI using realistic Monte Carlo simulations that closely reproduce the response of a SPECT imaging system. Anatomical input data for the SPECT simulations are obtained from this 3D T1-weighted MRI, while functional input data result from an inter-individual analysis of anatomically standardized SPECT data. The method makes it possible to control the 'brain perfusion' function by proposing a theoretical model of brain perfusion from measurements performed on real SPECT images. Our method provides an absolute gold standard for assessing MRI/SPECT registration method accuracy since, by construction, the SPECT data are perfectly registered with the MRI data. The proposed methodology has been applied to create a theoretical model of normal brain perfusion and ictal brain perfusion characteristic of mesial temporal lobe epilepsy. To approach realistic and unbiased perfusion models, real SPECT data were corrected for uniform attenuation, scatter and partial volume effect. An anatomic standardization was used to account for anatomic variability between subjects. Realistic simulations of normal and ictal SPECT deduced from these perfusion models are presented. The comparison of real and simulated SPECT images showed relative differences in regional activity concentration of less than 20% in most anatomical structures, for both normal and ictal data, suggesting realistic models of perfusion distributions for evaluation purposes. Inter-hemispheric asymmetry coefficients measured on simulated data were

SPECT/CT workflow and imaging protocols

Energy Technology Data Exchange (ETDEWEB)

Beckers, Catherine [University Hospital of Liege, Division of Nuclear Medicine and Oncological Imaging, Department of Medical Physics, Liege (Belgium); Hustinx, Roland [University Hospital of Liege, Division of Nuclear Medicine and Oncological Imaging, Department of Medical Physics, Liege (Belgium); Domaine Universitaire du Sart Tilman, Service de Medecine Nucleaire et Imagerie Oncologique, CHU de Liege, Liege (Belgium)

2014-05-15

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

SPECT/CT workflow and imaging protocols

International Nuclear Information System (INIS)

Beckers, Catherine; Hustinx, Roland

2014-01-01

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

Effects of attenuation map accuracy on attenuation-corrected micro-SPECT images

NARCIS (Netherlands)

Wu, C.; Gratama van Andel, H.A.; Laverman, P.; Boerman, O.C.; Beekman, F.J.

2013-01-01

Background In single-photon emission computed tomography (SPECT), attenuation of photon flux in tissue affects quantitative accuracy of reconstructed images. Attenuation maps derived from X-ray computed tomography (CT) can be employed for attenuation correction. The attenuation coefficients as well

Quantitative study on lung volume and lung perfusion using SPECT and CT in thoracal tumors

International Nuclear Information System (INIS)

Beyer-Enke, S.A.; Goerich, J.; Strauss, L.G.

1988-01-01

22 patients with space occupying lesions in the thoracal region were investigated by computer tomography and by perfusion scintigraphy using SPECT. In order to evaluate the CT images quantitatively, the lung volume was determined using approximation method and compared with the perfusion in the SPECT study. For this, anatomically equivalent transaxial SPECT slices had been coordinated to the CT slices. Between the determined lung volumes and the activity in the ocrresponding layers, a statistically significant correlation was found. It could be shown that the stronger perfusion, frequently observed at the right side of the healthy lung, may be explained by an higher volume of the right pulmonary lobe. Whereas in benign displacing processes the relation activity to volume was similar to the one of the healthy lung, a strongly reduced perfusion together with inconspicuous lung volumes became apparent with malignant tumors. In addition to the great morphological evidence of CT and SPECT studies, additional informations regarding the dignity of displacing processes may be derived from the quantitative evaluation of both methods. (orig.) [de

Clinical assessment of SPECT/CT co-registration image fusion

International Nuclear Information System (INIS)

Zhou Wen; Luan Zhaosheng; Peng Yong

2004-01-01

Objective: Study the methodology of the SPECT/CT co-registration image fusion, and Assessment the Clinical application value. Method: 172 patients who underwent SPECT/CT image fusion during 2001-2003 were studied, 119 men, 53 women. 51 patients underwent 18FDG image +CT, 26 patients underwent 99m Tc-RBC Liver pool image +CT, 43 patients underwent 99mTc-MDP Bone image +CT, 18 patients underwent 99m Tc-MAA Lung perfusion image +CT. The machine is Millium VG SPECT of GE Company. All patients have been taken three steps image: X-ray survey, X-ray transmission and nuclear emission image (Including planer imaging, SPECT or 18 F-FDG of dual head camera) without changing the position of the patients. We reconstruct the emission image with X-ray map and do reconstruction, 18FDG with COSEM and 99mTc with OSEM. Then combine the transmission image and the reconstructed emission image. We use different process parameters in deferent image methods. The accurate rate of SPECT/CT image fusion were statistics, and compare their accurate with that of single nuclear emission image. Results: The nuclear image which have been reconstructed by X-ray attenuation and OSEM are apparent better than pre-reconstructed. The post-reconstructed emission images have no scatter lines around the organs. The outline between different issues is more clear than before. The validity of All post-reconstructed images is better than pre-reconstructed. SPECT/CT image fusion make localization have worthy bases. 138 patients, the accuracy of SPECT/CT image fusion is 91.3% (126/138), whereas 60(88.2%) were found through SPECT/CT image fusion, There are significant difference between them(P 99m Tc- RBC-SPECT +CT image fusion, but 21 of them were inspected by emission image. In BONE 99m Tc -MDP-SPECT +CT image fusion, 4 patients' removed bone(1-6 months after surgery) and their relay with normal bone had activity, their morphologic and density in CT were different from normal bones. 11 of 20 patients who could

In vivo characteristics of IBZM in rat brains: an agent for quantitative SPECT imaging of dopamine D[sub 2] receptors; Preparation of [sup 125]I-IBZM and its biodistribution and kinetic properties

Energy Technology Data Exchange (ETDEWEB)

Matsumura, Kaname; Nakashima, Hiromichi; Nakagawa, Tsuyoshi [Mie Univ., Tsu (Japan). School of Medicine; Toyama, Hiroshi; Ichise, Masanori; Kurami, Miki; Maeda, Hisato; Takeuchi, Akira; Koga, Sukehiko

1994-05-01

[sup 123]I-(S)-(-)-3-iodo-2-hydroxy-6-methoxy-N-[(1-ethyl-2-pyrrolidinyl) methyl]-benzamide (IBZM) is a CNS dopamine D[sub 2] receptor imaging agent for SPECT and has already been used clinically in the United States, Canada and Europe. However, methods of quantitative SPECT measurement of the D[sub 2] receptor density have not been well established. We performed in vivo biodistribution studies of [sup 125]I-IBZM in rat brains as the first step toward establishment of a basis for quantitative SPECT imaging of D[sub 2] receptors in humans. [sup 125]I-IBZM was prepared by the chloramine-T method. Radiochemical yields were 80 to 90% and radiochemical purity was 94.7% on day 81 after labeling. At 10, 30, 60 and 120 min after injection of the radiopharmaceutical, the percent uptakes (% dose/g) in the rat striatum were 2.9, 1.9, 1.7 and 1.0, respectively. These kinetic data were considered suitable for SPECT imagings. Pretreatment with haloperidol (1 mg/kg) blocked specific striatal uptake and there was a significant reduction in the uptake to 40.9% of the unblocked uptake at 60 min after injection (p=0.006). The regional IBZM uptake ratio of striatum-to-cerebellum increased steadily from 1.7 at 10 min to 5.7 at 120 min. This suggests that SPECT imaging must be done during fixed time after tracer injection for the semiquantitative ratio to be meaningful. (author).

Improving quantitative dosimetry in (177)Lu-DOTATATE SPECT by energy window-based scatter corrections

DEFF Research Database (Denmark)

de Nijs, Robin; Lagerburg, Vera; Klausen, Thomas L

2014-01-01

and the activity, which depends on the collimator type, the utilized energy windows and the applied scatter correction techniques. In this study, energy window subtraction-based scatter correction methods are compared experimentally and quantitatively. MATERIALS AND METHODS: (177)Lu SPECT images of a phantom...... technique, the measured ratio was close to the real ratio, and the differences between spheres were small. CONCLUSION: For quantitative (177)Lu imaging MEGP collimators are advised. Both energy peaks can be utilized when the ESSE correction technique is applied. The difference between the calculated...

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

International Nuclear Information System (INIS)

Okuda, Ituko; Maruno, Hiromasa; Mori, Kazuaki; Kohno, Tadashi; Kokubo, Takashi

2007-01-01

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

A small-animal imaging system capable of multipinhole circular/helical SPECT and parallel-hole SPECT

International Nuclear Information System (INIS)

Qian Jianguo; Bradley, Eric L.; Majewski, Stan; Popov, Vladimir; Saha, Margaret S.; Smith, Mark F.; Weisenberger, Andrew G.; Welsh, Robert E.

2008-01-01

We have designed and built a small-animal single-photon emission computed tomography (SPECT) imaging system equipped with parallel-hole and multipinhole collimators and capable of circular or helical SPECT. Copper-beryllium parallel-hole collimators suitable for imaging the ∼35 keV photons from the decay of 125 I have been built and installed to achieve useful spatial resolution over a range of object-detector distances and to reduce imaging time on our dual-detector array. To address the resolution limitations in the parallel-hole SPECT and the sensitivity and limited field of view of single-pinhole SPECT, we have incorporated multipinhole circular and helical SPECT in addition to expanding the parallel-hole SPECT capabilities. The pinhole SPECT system is based on a 110 mm diameter circular detector equipped with a pixellated NaI(Tl) scintillator array (1x1x5 mm 3 /pixel). The helical trajectory is accomplished by two stepping motors controlling the rotation of the detector-support gantry and displacement of the animal bed along the axis of rotation of the gantry. Results obtained in SPECT studies of various phantoms show an enlarged field of view, very good resolution and improved sensitivity using multipinhole circular or helical SPECT. Collimators with one, three and five, 1-mm-diameter pinholes have been implemented and compared in these tests. Our objective is to develop a system on which one may readily select a suitable mode of either parallel-hole SPECT or pinhole circular or helical SPECT for a variety of small animal imaging applications

Improved quantitative 90 Y bremsstrahlung SPECT/CT reconstruction with Monte Carlo scatter modeling.

Science.gov (United States)

Dewaraja, Yuni K; Chun, Se Young; Srinivasa, Ravi N; Kaza, Ravi K; Cuneo, Kyle C; Majdalany, Bill S; Novelli, Paula M; Ljungberg, Michael; Fessler, Jeffrey A

2017-12-01

In 90 Y microsphere radioembolization (RE), accurate post-therapy imaging-based dosimetry is important for establishing absorbed dose versus outcome relationships for developing future treatment planning strategies. Additionally, accurately assessing microsphere distributions is important because of concerns for unexpected activity deposition outside the liver. Quantitative 90 Y imaging by either SPECT or PET is challenging. In 90 Y SPECT model based methods are necessary for scatter correction because energy window-based methods are not feasible with the continuous bremsstrahlung energy spectrum. The objective of this work was to implement and evaluate a scatter estimation method for accurate 90 Y bremsstrahlung SPECT/CT imaging. Since a fully Monte Carlo (MC) approach to 90 Y SPECT reconstruction is computationally very demanding, in the present study the scatter estimate generated by a MC simulator was combined with an analytical projector in the 3D OS-EM reconstruction model. A single window (105 to 195-keV) was used for both the acquisition and the projector modeling. A liver/lung torso phantom with intrahepatic lesions and low-uptake extrahepatic objects was imaged to evaluate SPECT/CT reconstruction without and with scatter correction. Clinical application was demonstrated by applying the reconstruction approach to five patients treated with RE to determine lesion and normal liver activity concentrations using a (liver) relative calibration. There was convergence of the scatter estimate after just two updates, greatly reducing computational requirements. In the phantom study, compared with reconstruction without scatter correction, with MC scatter modeling there was substantial improvement in activity recovery in intrahepatic lesions (from > 55% to > 86%), normal liver (from 113% to 104%), and lungs (from 227% to 104%) with only a small degradation in noise (13% vs. 17%). Similarly, with scatter modeling contrast improved substantially both visually and in

A method for energy window optimization for quantitative tasks that includes the effects of model-mismatch on bias: application to Y-90 bremsstrahlung SPECT imaging

International Nuclear Information System (INIS)

Rong Xing; Du Yong; Frey, Eric C

2012-01-01

Quantitative Yttrium-90 ( 90 Y) bremsstrahlung single photon emission computed tomography (SPECT) imaging has shown great potential to provide reliable estimates of 90 Y activity distribution for targeted radionuclide therapy dosimetry applications. One factor that potentially affects the reliability of the activity estimates is the choice of the acquisition energy window. In contrast to imaging conventional gamma photon emitters where the acquisition energy windows are usually placed around photopeaks, there has been great variation in the choice of the acquisition energy window for 90 Y imaging due to the continuous and broad energy distribution of the bremsstrahlung photons. In quantitative imaging of conventional gamma photon emitters, previous methods for optimizing the acquisition energy window assumed unbiased estimators and used the variance in the estimates as a figure of merit (FOM). However, for situations, such as 90 Y imaging, where there are errors in the modeling of the image formation process used in the reconstruction there will be bias in the activity estimates. In 90 Y bremsstrahlung imaging this will be especially important due to the high levels of scatter, multiple scatter, and collimator septal penetration and scatter. Thus variance will not be a complete measure of reliability of the estimates and thus is not a complete FOM. To address this, we first aimed to develop a new method to optimize the energy window that accounts for both the bias due to model-mismatch and the variance of the activity estimates. We applied this method to optimize the acquisition energy window for quantitative 90 Y bremsstrahlung SPECT imaging in microsphere brachytherapy. Since absorbed dose is defined as the absorbed energy from the radiation per unit mass of tissues in this new method we proposed a mass-weighted root mean squared error of the volume of interest (VOI) activity estimates as the FOM. To calculate this FOM, two analytical expressions were derived for

A method for energy window optimization for quantitative tasks that includes the effects of model-mismatch on bias: application to Y-90 bremsstrahlung SPECT imaging.

Science.gov (United States)

Rong, Xing; Du, Yong; Frey, Eric C

2012-06-21

Quantitative Yttrium-90 ((90)Y) bremsstrahlung single photon emission computed tomography (SPECT) imaging has shown great potential to provide reliable estimates of (90)Y activity distribution for targeted radionuclide therapy dosimetry applications. One factor that potentially affects the reliability of the activity estimates is the choice of the acquisition energy window. In contrast to imaging conventional gamma photon emitters where the acquisition energy windows are usually placed around photopeaks, there has been great variation in the choice of the acquisition energy window for (90)Y imaging due to the continuous and broad energy distribution of the bremsstrahlung photons. In quantitative imaging of conventional gamma photon emitters, previous methods for optimizing the acquisition energy window assumed unbiased estimators and used the variance in the estimates as a figure of merit (FOM). However, for situations, such as (90)Y imaging, where there are errors in the modeling of the image formation process used in the reconstruction there will be bias in the activity estimates. In (90)Y bremsstrahlung imaging this will be especially important due to the high levels of scatter, multiple scatter, and collimator septal penetration and scatter. Thus variance will not be a complete measure of reliability of the estimates and thus is not a complete FOM. To address this, we first aimed to develop a new method to optimize the energy window that accounts for both the bias due to model-mismatch and the variance of the activity estimates. We applied this method to optimize the acquisition energy window for quantitative (90)Y bremsstrahlung SPECT imaging in microsphere brachytherapy. Since absorbed dose is defined as the absorbed energy from the radiation per unit mass of tissues in this new method we proposed a mass-weighted root mean squared error of the volume of interest (VOI) activity estimates as the FOM. To calculate this FOM, two analytical expressions were

Quantitation of myocardial blood flow and myocardial flow reserve with {sup 99m}Tc-sestamibi dynamic SPECT/CT to enhance detection of coronary artery disease

Energy Technology Data Exchange (ETDEWEB)

Hsu, Bailing [University of Missouri-Columbia, Nuclear Science and Engineering Institute, Columbia, MO (United States); Chen, Fu-Chung; Chen, Chien-Cheng [Show Chwan Memorial Hospital, Section of Cardiology, Department of Internal Medicine, Changhua (China); Wu, Tao-Cheng [Taipei Veterans General Hospital, Section of Cardiology, Department of Internal Medicine, Taipei (China); Huang, Wen-Sheng [Changhua Christian Hospital, Department of Medical Research and Department of Nuclear Medicine, Changhua (China); Hou, Po-Nien [Chang Bing Show Chwan Memorial Hospital, Department of Nuclear Medicine, Lukong Town, Changhua Shien (China); Hung, Guang-Uei [Chang Bing Show Chwan Memorial Hospital, Department of Nuclear Medicine, Lukong Town, Changhua Shien (China); Central Taiwan University of Science and Technology, Department of Medical Imaging and Radiological Science, Taichung (China); China Medical University, Department of Biomedical Imaging and Radiological Science, Taichung (China)

2014-12-15

Conventional dual-head single photon emission computed tomography (SPECT)/CT systems capable of fast dynamic SPECT (DySPECT) imaging have a potential for flow quantitation. This study introduced a new method to quantify myocardial blood flow (MBF) and myocardial flow reserve (MFR) with DySPECT scan and evaluated the diagnostic performance of detecting coronary artery disease (CAD) compared with perfusion using invasive coronary angiography (CAG) as the reference standard. This study included 21 patients with suspected or known CAD who had received DySPECT, ECG-gated SPECT (GSPECT), and CAG (13 with ≥50 % stenosis in any vessel; non-CAD group: 8 with patent arteries or <50 % stenosis). DySPECT and GSPECT scans were performed on a widely used dual-head SPECT/CT scanner. The DySPECT imaging protocol utilized 12-min multiple back-and-forth gantry rotations during injections of {sup 99m}Tc-sestamibi (MIBI) tracer at rest or dipyridamole-stress stages. DySPECT images were reconstructed with full physical corrections and converted to the physical unit of becquerels per milliliter. Stress MBF (SMBF), rest MBF (RMBF), and MFR were quantified by a one-tissue compartment flow model using time-activity curves derived from DySPECT images. Perfusion images were processed for GSPECT scan and interpreted to obtain summed stress score (SSS) and summed difference score (SDS). Receiver-operating characteristic (ROC) analyses were conducted to evaluate the diagnostic performance of flow and perfusion. Using the criteria of ≥50 % stenosis as positive CAD, areas under the ROC curve (AUCs) of flow assessment were overall significantly greater than those of perfusion. For patient-based analysis, AUCs for MFR, SMBF, SSS, and SDS were 0.91 ± 0.07, 0.86 ± 0.09, 0.64 ± 0.12, and 0.59 ± 0.13. For vessel-based analysis, AUCs for MFR, SMBF, SSS, and SDS were 0.81 ± 0.05, 0.76 ± 0.06, 0.62 ± 0.07, and 0.56 ± 0.08, respectively. The preliminary data suggest that MBF quantitation with a

SPECT data acquisition and image reconstruction in a stationary small animal SPECT/MRI system

Science.gov (United States)

Xu, Jingyan; Chen, Si; Yu, Jianhua; Meier, Dirk; Wagenaar, Douglas J.; Patt, Bradley E.; Tsui, Benjamin M. W.

2010-04-01

The goal of the study was to investigate data acquisition strategies and image reconstruction methods for a stationary SPECT insert that can operate inside an MRI scanner with a 12 cm bore diameter for simultaneous SPECT/MRI imaging of small animals. The SPECT insert consists of 3 octagonal rings of 8 MR-compatible CZT detectors per ring surrounding a multi-pinhole (MPH) collimator sleeve. Each pinhole is constructed to project the field-of-view (FOV) to one CZT detector. All 24 pinholes are focused to a cylindrical FOV of 25 mm in diameter and 34 mm in length. The data acquisition strategies we evaluated were optional collimator rotations to improve tomographic sampling; and the image reconstruction methods were iterative ML-EM with and without compensation for the geometric response function (GRF) of the MPH collimator. For this purpose, we developed an analytic simulator that calculates the system matrix with the GRF models of the MPH collimator. The simulator was used to generate projection data of a digital rod phantom with pinhole aperture sizes of 1 mm and 2 mm and with different collimator rotation patterns. Iterative ML-EM reconstruction with and without GRF compensation were used to reconstruct the projection data from the central ring of 8 detectors only, and from all 24 detectors. Our results indicated that without GRF compensation and at the default design of 24 projection views, the reconstructed images had significant artifacts. Accurate GRF compensation substantially improved the reconstructed image resolution and reduced image artifacts. With accurate GRF compensation, useful reconstructed images can be obtained using 24 projection views only. This last finding potentially enables dynamic SPECT (and/or MRI) studies in small animals, one of many possible application areas of the SPECT/MRI system. Further research efforts are warranted including experimentally measuring the system matrix for improved geometrical accuracy, incorporating the co

Brain perfusion SPECT imaging before and during the acetazolamide test using sup 99m Tc-HMPAO

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Matsuda, Hiroshi; Higashi, Sotaro; Kinuya, Keiko; Tsuji, Shiro; Sumiya, Hisashi; Hisada, Kinichi; Yamashita, Junkoh (Kanazawa Univ. (Japan). School of Medicine)

1990-05-01

A new method using brain perfusion {sup 99m}Tc-HMPAO SPECT imaging was developed for evaluating cerebral perfusion reserve by the acetazolamide test with a short period. The first SPECT study was carried out for 13.5 min to obtain SPECT images at the resting state after 3 min postinjection of 555 MBq (15 mCi) of {sup 99m}Tc-HMPAO. At the same time as the start of the first SPECT study, 1 g of acetazolamide was intravenously injected. Immediately after the stop of the 1st SPECT study, 925 MBq (25 mCi) of {sup 99m}Tc-HMPAO from the same vial as in the first study was additionally injected. Three minutes later the second SPECT study was carried out for 10 min. After reconstruction the tomographic images in the first study were subtracted from the images in the second study to obtain those during the acetazolamide test after correction of the time differences in data acquisition between the two studies. This subtraction technique gives independent brain perfusion SPECT images before and during the acetazolamide test. Besides, the regional flow changes during the test were quantitatively analyzed. In conclusion this method seems to be practically useful for evaluating regional brain perfusion before and during drug treatments as a consecutive study with a short period of approximately 30 min. (author).

SPECT imaging with resolution recovery

International Nuclear Information System (INIS)

Bronnikov, A. V.

2011-01-01

Single-photon emission computed tomography (SPECT) is a method of choice for imaging spatial distributions of radioisotopes. Many applications of this method are found in nuclear industry, medicine, and biomedical research. We study mathematical modeling of a micro-SPECT system by using a point-spread function (PSF) and implement an OSEM-based iterative algorithm for image reconstruction with resolution recovery. Unlike other known implementations of the OSEM algorithm, we apply en efficient computation scheme based on a useful approximation of the PSF, which ensures relatively fast computations. The proposed approach can be applied with the data acquired with any type of collimators, including parallel-beam fan-beam, cone-beam and pinhole collimators. Experimental results obtained with a micro SPECT system demonstrate high efficiency of resolution recovery. (authors)

Intravenous streptokinase therapy in acute myocardial infarction: Assessment of therapy effects by quantitative 201Tl myocardial imaging (including SPECT) and radionuclide ventriculography

International Nuclear Information System (INIS)

Koehn, H.; Bialonczyk, C.; Mostbeck, A.; Frohner, K.; Unger, G.; Steinbach, K.

1984-01-01

To evaluate a potential beneficial effect of systemic streptokinase therapy in acute myocardial infarction, 36 patients treated with streptokinase intravenously were assessed by radionuclide ventriculography and quantitative 201 Tl myocardial imaging (including SPECT) in comparison with 18 conventionally treated patients. Patients after thrombolysis had significantly higher EF, PFR, and PER as well as fewer wall motion abnormalities compared with controls. These differences were also observed in the subset of patients with anterior wall infarction (AMI), but not in patients with inferior wall infarction (IMI). Quantitative 201 Tl imaging demonstrated significantly smaller percent myocardial defects and fewer pathological stress segments in patients with thrombolysis compared with controls. The same differences were also found in both AMI and IMI patients. Our data suggest a favorable effect of intravenous streptokinase on recovery of left ventricular function and myocardial salvage. Radionuclide ventriculography and quantitative 201 Tl myocardial imaging seem to be reliable tools for objective assessment of therapy effects. (orig.)

Technical approach to improvement of SPECT images

International Nuclear Information System (INIS)

Fukukita, Hiroyoshi

1985-01-01

At present, a large number of SPECT systems are being widely used in Japan, hence, it is reasonable for us to know the physical and imaging characteristics of these SPECT devices, and also to recommend the optimum utility of SPECT systems. For this reason, a survey respect of characteristics of the commercialy available SPECT devices was carried out. In addition to this, various factors which have significant influence over SPECT image quality, such as, data acquisition matrix, reconstruction filter, γ-ray attenuation correction and daily quality control procedure, were also investigated. The materials used for this study are PET/SPECT phantom, Alderson liver phantom filled with Tc-99m solution, and either LFOV-E or ZLC-7500 interfaced to Scintipac 2400 minicomputer with 256 K byte of memory. Following are the results of this study. 1) The suitable data acquisition procedure was 128 x 128 matrix for linear sampling and approximately 64 views for angular sampling. 2) Reconstructed image using pre-processing filter with Wiener and Butterworth filters provided high quality image as compared with the Ramp filter. 3) Weighted backprojection method (WBP) proposed by Tanaka was superior to other methods, such as Sorenson method and Chang method in the object with non-uniform distribution of radionuclide. 4) It was found that uniformity correction of gamma camera and precise adjustment of the center of rotation are most important to maintain the images with a high quality. (author)

High-resolution SPECT for small-animal imaging

International Nuclear Information System (INIS)

Qi Yujin

2006-01-01

This article presents a brief overview of the development of high-resolution SPECT for small-animal imaging. A pinhole collimator has been used for high-resolution animal SPECT to provide better spatial resolution and detection efficiency in comparison with a parallel-hole collimator. The theory of imaging characteristics of the pinhole collimator is presented and the designs of the pinhole aperture are discussed. The detector technologies used for the development of small-animal SPECT and the recent advances are presented. The evolving trend of small-animal SPECT is toward a multi-pinhole and a multi-detector system to obtain a high resolution and also a high detection efficiency. (authors)

Quantitation of myocardial blood flow and myocardial flow reserve with 99mTc-sestamibi dynamic SPECT/CT to enhance detection of coronary artery disease

International Nuclear Information System (INIS)

Hsu, Bailing; Chen, Fu-Chung; Chen, Chien-Cheng; Wu, Tao-Cheng; Huang, Wen-Sheng; Hou, Po-Nien; Hung, Guang-Uei

2014-01-01

Conventional dual-head single photon emission computed tomography (SPECT)/CT systems capable of fast dynamic SPECT (DySPECT) imaging have a potential for flow quantitation. This study introduced a new method to quantify myocardial blood flow (MBF) and myocardial flow reserve (MFR) with DySPECT scan and evaluated the diagnostic performance of detecting coronary artery disease (CAD) compared with perfusion using invasive coronary angiography (CAG) as the reference standard. This study included 21 patients with suspected or known CAD who had received DySPECT, ECG-gated SPECT (GSPECT), and CAG (13 with ≥50 % stenosis in any vessel; non-CAD group: 8 with patent arteries or 99m Tc-sestamibi (MIBI) tracer at rest or dipyridamole-stress stages. DySPECT images were reconstructed with full physical corrections and converted to the physical unit of becquerels per milliliter. Stress MBF (SMBF), rest MBF (RMBF), and MFR were quantified by a one-tissue compartment flow model using time-activity curves derived from DySPECT images. Perfusion images were processed for GSPECT scan and interpreted to obtain summed stress score (SSS) and summed difference score (SDS). Receiver-operating characteristic (ROC) analyses were conducted to evaluate the diagnostic performance of flow and perfusion. Using the criteria of ≥50 % stenosis as positive CAD, areas under the ROC curve (AUCs) of flow assessment were overall significantly greater than those of perfusion. For patient-based analysis, AUCs for MFR, SMBF, SSS, and SDS were 0.91 ± 0.07, 0.86 ± 0.09, 0.64 ± 0.12, and 0.59 ± 0.13. For vessel-based analysis, AUCs for MFR, SMBF, SSS, and SDS were 0.81 ± 0.05, 0.76 ± 0.06, 0.62 ± 0.07, and 0.56 ± 0.08, respectively. The preliminary data suggest that MBF quantitation with a conventional SPECT/CT system and the flow quantitation method is a clinically effective approach to enhance CAD detection. (orig.)

The clinical use of brain SPECT imaging in neuropsychiatry

International Nuclear Information System (INIS)

Amen, Daniel G; Wu, Joseph C; Carmichael, Blake

2003-01-01

This article reviews the literature on brain SPECT imaging in brain trauma, dementia, and temporal lobe epilepsy. Brain SPECT allows clinicians the ability to view cerebral areas of healthy, low, and excessive perfusion. This information can be correlated with what is known about the function or dysfunction of each area. SPECT has a number of advantages over other imaging techniques, including wider availability, lower cost, and high quality resolution with multi-headed cameras. There are a number of issues that compromise the effective use of SPECT, including low quality of some imaging cameras, and variability of image rendering and readings (Au)

Computed-tomography-guided anatomic standardization for quantitative assessment of dopamine transporter SPECT

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Yokoyama, Kota [National Center of Neurology and Psychiatry, Department of Radiology, Tokyo (Japan); National Center of Neurology and Psychiatry, Integrative Brain Imaging Center, Tokyo (Japan); Imabayashi, Etsuko; Matsuda, Hiroshi [National Center of Neurology and Psychiatry, Integrative Brain Imaging Center, Tokyo (Japan); Sumida, Kaoru; Sone, Daichi; Kimura, Yukio; Sato, Noriko [National Center of Neurology and Psychiatry, Department of Radiology, Tokyo (Japan); Mukai, Youhei; Murata, Miho [National Center of Neurology and Psychiatry, Department of Neurology, Tokyo (Japan)

2017-03-15

For the quantitative assessment of dopamine transporter (DAT) using [{sup 123}I]FP-CIT single-photon emission computed tomography (SPECT) (DaTscan), anatomic standardization is preferable for achieving objective and user-independent quantification of striatal binding using a volume-of-interest (VOI) template. However, low accumulation of DAT in Parkinson's disease (PD) would lead to a deformation error when using a DaTscan-specific template without any structural information. To avoid this deformation error, we applied computed tomography (CT) data obtained using SPECT/CT equipment to anatomic standardization. We retrospectively analyzed DaTscan images of 130 patients with parkinsonian syndromes (PS), including 80 PD and 50 non-PD patients. First we segmented gray matter from CT images using statistical parametric mapping 12 (SPM12). These gray-matter images were then anatomically standardized using the diffeomorphic anatomical registration using exponentiated Lie algebra (DARTEL) algorithm. Next, DaTscan images were warped with the same parameters used in the CT anatomic standardization. The target striatal VOIs for decreased DAT in PD were generated from the SPM12 group comparison of 20 DaTscan images from each group. We applied these VOIs to DaTscan images of the remaining patients in both groups and calculated the specific binding ratios (SBRs) using nonspecific counts in a reference area. In terms of the differential diagnosis of PD and non-PD groups using SBR, we compared the present method with two other methods, DaTQUANT and DaTView, which have already been released as software programs for the quantitative assessment of DaTscan images. The SPM12 group comparison showed a significant DAT decrease in PD patients in the bilateral whole striatum. Of the three methods assessed, the present CT-guided method showed the greatest power for discriminating PD and non-PD groups, as it completely separated the two groups. CT-guided anatomic standardization using

3D composite image, 3D MRI, 3D SPECT, hydrocephalus

International Nuclear Information System (INIS)

Mito, T.; Shibata, I.; Sugo, N.; Takano, M.; Takahashi, H.

2002-01-01

2 by the use of a program prepared by combining the advantage of a surface rendering method with that of a volume rendering method by means of the general-purpose visualization software AVS-MV (Application Visualization System Medical Viewer). The AVS-MV permits production of semitransparent images as well, so that metabolic and physiological functions in internal tissues with the same threshold value can be seen through external tissues. The voxel and threshold distribution curve was plotted and analyzed by this software. The distribution of voxel in normal individuals shows such a bimodal curve that RI count presents a trough at a threshold value of 40% and a crest at 70%. In hydrocephalus, on the other hand, the 40% region showed an increase and 70% region showed a decrease . After shunt operation for hydrocephalus, with improvement in symptoms, the 40% region decreased and 70% region increased, so that a normal pattern was approached. This composite 3D MRI and SPECT imaging technique made it possible not only to establish an intracranial position in SPECT, but also to assess the profile of cerebral circulation around the cerebral venuicles. Analysis of these 3D composite images permits quantitative expression of brain volume in SPECT and extensive elucidation of the cerebral circulation profile in morphological detail. This analysis is, therefore, considered to contribute largely to the development of functional images

Combining SPECT and Quantitative EEG Analysis for the Automated Differential Diagnosis of Disorders with Amnestic Symptoms

Directory of Open Access Journals (Sweden)

Yvonne Höller

2017-09-01

Full Text Available Single photon emission computed tomography (SPECT and Electroencephalography (EEG have become established tools in routine diagnostics of dementia. We aimed to increase the diagnostic power by combining quantitative markers from SPECT and EEG for differential diagnosis of disorders with amnestic symptoms. We hypothesize that the combination of SPECT with measures of interaction (connectivity in the EEG yields higher diagnostic accuracy than the single modalities. We examined 39 patients with Alzheimer's dementia (AD, 69 patients with depressive cognitive impairment (DCI, 71 patients with amnestic mild cognitive impairment (aMCI, and 41 patients with amnestic subjective cognitive complaints (aSCC. We calculated 14 measures of interaction from a standard clinical EEG-recording and derived graph-theoretic network measures. From regional brain perfusion measured by 99mTc-hexamethyl-propylene-aminoxime (HMPAO-SPECT in 46 regions, we calculated relative cerebral perfusion in these patients. Patient groups were classified pairwise with a linear support vector machine. Classification was conducted separately for each biomarker, and then again for each EEG- biomarker combined with SPECT. Combination of SPECT with EEG-biomarkers outperformed single use of SPECT or EEG when classifying aSCC vs. AD (90%, aMCI vs. AD (70%, and AD vs. DCI (100%, while a selection of EEG measures performed best when classifying aSCC vs. aMCI (82% and aMCI vs. DCI (90%. Only the contrast between aSCC and DCI did not result in above-chance classification accuracy (60%. In general, accuracies were higher when measures of interaction (i.e., connectivity measures were applied directly than when graph-theoretical measures were derived. We suggest that quantitative analysis of EEG and machine-learning techniques can support differentiating AD, aMCI, aSCC, and DCC, especially when being combined with imaging methods such as SPECT. Quantitative analysis of EEG connectivity could become

Qualitative and quantitative evaluation of renal parenchymal damage by 99mTc-DMSA planar and SPECT scintigraphy

International Nuclear Information System (INIS)

Itoh, Kazuo; Yamashita, Tetsufumi; Tsukamoto, Eriko; Nonomura, Katsuya; Furudate, Masayori; Koyanagi, Tomohiko

1995-01-01

The initial 99m Tc-DMSA studies carried out over a four year period in 229 patients with various heterogenic causes of lower urinary tract abnormalities were reviewed. Anatomical damage to the renal parenchyma was graded by means of planar and SPECT studies into a six group classification proposed by Monsour et al.: grade 0 (normal), I (equivocal), II (single defect), III (more than 2 defects), IV (contracted or small) and V (no visualization). Parenchymal uptake of 99m Tc-DMSA was quantitated from planar images at 2 hours postinjection by a computer assisted gamma camera method. SPECT studies could enhance the pick-up rate for parenchymal uptake defects by a factor of 1.5 in comparison with planar imaging. The incidence of anatomical damage to the renal parenchyma increased with a high radiological grade for VUR, and renal uptake per injection dose of 99m Tc-DMSA by the individual kidney significantly decreased in grades III and IV of the anatomical classification. These data revealed that 99m Tc-DMSA planar is still useful for evaluating gross structural damage and for quantitative evaluation of the kidney with computer assistance. SPECT scintigraphy is more effective in disclosing anatomical damage to the renal parenchyma than planar, although it needs further discussion as to whether SPECT may increase sensitivity with minimal or no adverse affect on specificity. (author)

Labeled receptor ligands for spect

International Nuclear Information System (INIS)

Kung, H.F.

1989-01-01

Receptor specific imaging agents for single photon emission computed tomography (SPECT) can potentially be useful in the understanding of basic biochemistry and pharmacology of receptors. SPECT images may also provide tools for evaluation of density and binding kinetics of a specific receptor, information important for diagnosis and patient management. Basic requirements for receptor imaging agents are: (a) they are labeled with short-lived isotopes, (b) they show high selectivity and specific uptake, (c) they exhibit high target/background ratio, and (d) they can be modeled to obtain quantitative information. Several good examples of CNS receptor specific ligands labeled with I-123 have been developed, including iodoQNB, iodoestrogen iodobenzadiazepine, iodobenazepine, iodobenzamides for muscarinic, estrogen benzadiazepine, D-1 and D-2 dopamine receptors. With the advent of newer and faster SPECT imaging devices, it may be feasible to quantitate the receptor density by in vivo imaging techniques. These new brain imaging agents can provide unique diagnostic information, which may not be available through other imaging modalities, such as CT and MRI

Stereotactic radiosurgery planning with ictal SPECT images

International Nuclear Information System (INIS)

Ackerly, T.; RMIT University, Bundoora, VIC; Geso, M.; O'Keefe, G.; Smith, R.

2004-01-01

This paper is motivated by a clinical requirement to utilise ictal SPECT images for target localisation in stereotactic radiosurgery treatment planning using the xknife system which only supports CT and MRI images. To achieve this, the SPECT images were converted from raw (pixel data only) format into a part 10 compliant DICOM CT fileset. The minimum requirements for the recasting of a raw format image as DICOM CT or MRI data set are described in detail. The method can be applied to the importation of raw format images into any radiotherapy treatment planning system that supports CT or MRI import. It is demonstrated that the combination of the low spatial resolution SPECT images, depicting functional information, with high spatial resolution MRI images, which show the structural information, is suitable for stereotactic radiosurgery treatment planning. Copyright (2004) Australasian College of Physical Scientists and Engineers in Medicine

Study on SPECT image for children with cerebral infarction

International Nuclear Information System (INIS)

Xie Wenhuang; Xie Zhichun; Chen Yucai; Lin Haoxue; Zheng Aidong; Xie Hui

1998-01-01

To explore the diagnostic value of SPECT image for children with cerebral infarction (CCI), comparative research was made on 26 cases undergoing regional cerebral perfusion (rCP) image between SPECT imaging and CT scanning. The results showed that the rCP in the infarct and its distant area was decreased. The positive rate of SPECT and CT were 92.3% (24/26) and 84.5% (22/26) respectively. The difference was not significant (P = 0.67, P>0.05). But, the positive rate of SPECT image 2 days after onset in 9 CCI was 100% (9/9), significantly higher than 55.6% (5/9) in CT scanning (P = 0.04, P<0.05). These findings suggested that the SPECT imaging is a sensitive method for the early diagnosis of CCI, and also helpful for observation of the therapeutic effect and evaluation of the prognosis

Diagnostic role of (99)Tc(m)-MDP SPECT/CT combined SPECT/MRI Multi modality imaging for early and atypical bone metastases.

Science.gov (United States)

Chen, Xiao-Liang; Li, Qian; Cao, Lin; Jiang, Shi-Xi

2014-01-01

The bone metastasis appeared early before the bone imaging for most of the above patients. (99)Tc(m)-MDP ((99)Tc(m) marked methylene diphosphonate) bone imaging could diagnosis the bone metastasis with highly sensitivity, but with lower specificity. The aim of this study is to explore the diagnostic value of (99)Tc(m)-MDP SPECT/CT combined SPECT/MRI Multi modality imaging for the early period atypical bone metastases. 15 to 30 mCi (99)Tc(m)-MDP was intravenously injected to the 34 malignant patients diagnosed as doubtful early bone metastases. SPECT, CT and SPECT/CT images were captured and analyzed consequently. For the patients diagnosed as early period atypical bone metastases by SPECT/CT, combining the SPECT/CT and MRI together as the SPECT/MRI integrated image. The obtained SPECT/MRI image was analyzed and compared with the pathogenic results of patients. The results indicated that 34 early period doubtful metastatic focus, including 34 SPECT positive focus, 17 focus without special changes by using CT method, 11 bone metastases focus by using SPECT/CT method, 23 doubtful bone metastases focus, 8 doubtful bone metastases focus, 14 doubtful bone metastases focus and 2 focus without clear image. Totally, SPECT/CT combined with SPECT/MRI method diagnosed 30 bone metastatic focus and 4 doubtfully metastatic focus. In conclusion, (99)Tc(m)-MDP SPECT/CT combined SPECT/MRI Multi modality imaging shows a higher diagnostic value for the early period bone metastases, which also enhances the diagnostic accuracy rate.

Brain imaging during seizure: ictal brain SPECT

International Nuclear Information System (INIS)

Kottamasu, Sambasiva Rao

1997-01-01

The role of single photon computed tomography (SPECT) in presurgical localization of medically intractable complex partial epilepsy (CPE) in children is reviewed. 99m Technetium neurolite, a newer lipophylic agent with a high first pass brain extraction and little or no redistribution is injected during a seizure, while the child is monitored with a video recording and continuous EEG and SPECT imaging is performed in the next 1-3 hours with the images representing regional cerebral profusion at the time of injection. On SPECT studies performed with radiopharmaceutical injected during a seizure, ictal focus is generally hypervascular. Other findings on ictal brain SPECT include hypoperfusion of adjacent cerebral cortex and white matter, hyperperfusion of contralateral motor cortex, hyperperfusion of ipsilateral basal ganglia and thalamus, brain stem and contralateral cerebellum. Ictal brain SPECT is non-invasive, cost effective and highly sensitive for localization of epileptic focus in patients with intractable CPE. (author)

Peritoneal fluid causing inferior attenuation on SPECT thallium-201 myocardial imaging in women

International Nuclear Information System (INIS)

Rab, S.T.; Alazraki, N.P.; Guertler-Krawczynska, E.

1988-01-01

On SPECT thallium images, myocardial left ventricular (LV) anterior wall attenuation due to breast tissue is common in women. In contrast, in men, inferior wall counts are normally decreased compared to anterior counts. The purpose of this report is to describe cases of inferior wall attenuation of counts in women caused by peritoneal fluid, not myocardial disease. Twelve consecutive SPECT thallium myocardial studies performed in women on peritoneal dialysis, being evaluated for kidney transplant, were included in this study. For all studies, 3.5 mCi 201Tl were injected intravenously. Thirty-two images were acquired over 180 degrees (45 degrees RAO progressing to 45 degrees LPO) at 40 sec per stop. SPECT images were reviewed in short axis, horizontal long and vertical long axes. Data were also displayed in bullseye format with quantitative comparison to gender-matched normal files. Ten of 12 female patients studied had inferior wall defects on images, confirmed by bullseye display. All patients had approximately 2 liters of peritoneal fluid. Review of planar rotational views showed diaphragm elevation and fluid margin attenuations affecting left ventricular inferior wall. Thus, peritoneal fluid is a cause of inferior attenuation on 201Tl cardiac imaging

Absolute quantitation of myocardial blood flow with 201Tl and dynamic SPECT in canine: optimisation and validation of kinetic modelling

International Nuclear Information System (INIS)

Iida, Hidehiro; Kim, Kyeong-Min; Nakazawa, Mayumi; Sohlberg, Antti; Zeniya, Tsutomu; Hayashi, Takuya; Watabe, Hiroshi; Eberl, Stefan; Tamura, Yoshikazu; Ono, Yukihiko

2008-01-01

201 Tl has been extensively used for myocardial perfusion and viability assessment. Unlike 99m Tc-labelled agents, such as 99m Tc-sestamibi and 99m Tc-tetrofosmine, the regional concentration of 201 Tl varies with time. This study is intended to validate a kinetic modelling approach for in vivo quantitative estimation of regional myocardial blood flow (MBF) and volume of distribution of 201 Tl using dynamic SPECT. Dynamic SPECT was carried out on 20 normal canines after the intravenous administration of 201 Tl using a commercial SPECT system. Seven animals were studied at rest, nine during adenosine infusion, and four after beta-blocker administration. Quantitative images were reconstructed with a previously validated technique, employing OS-EM with attenuation-correction, and transmission-dependent convolution subtraction scatter correction. Measured regional time-activity curves in myocardial segments were fitted to two- and three-compartment models. Regional MBF was defined as the influx rate constant (K 1 ) with corrections for the partial volume effect, haematocrit and limited first-pass extraction fraction, and was compared with that determined from radio-labelled microspheres experiments. Regional time-activity curves responded well to pharmacological stress. Quantitative MBF values were higher with adenosine and decreased after beta-blocker compared to a resting condition. MBFs obtained with SPECT (MBF SPECT ) correlated well with the MBF values obtained by the radio-labelled microspheres (MBF MS ) (MBF SPECT = -0.067 + 1.042 x MBF MS , p 201 Tl and dynamic SPECT. (orig.)

Weighted backprojection implemented with a non-uniform attenuation map for improved SPECT quantitation

International Nuclear Information System (INIS)

Manglos, S.H.; Jaszczak, R.J.; Floyd, C.E.

1988-01-01

A method is developed to improve quantitation in SPECT imaging by using an attenuation compensation method which includes the correct non-uniform attenuation spatial distribution (''map''). The method is based on the technique of weighted back projection, previously developed for uniform attenuation. The method is tested by imaging a non-uniform phantom, reconstructing with the known attenuation map, and quantitatively comparing the resultant image with the known activity distribution. Reconstructed image profiles are dramatically improved in comparison to reconstructions without compensation or with an assumed uniform attenuation map. Contrast measurements further quantify the improvement. Line spread function distortions seen previously in non-uniform geometries are essentially eliminated by the method. Therefore, the method appears to be appropriate for these geometries, if the non-uniform map can be determined. Some additional image distortions introduced by the compensation method are noted and will require further study

Combined SPECT/CT and PET/CT for breast imaging

Energy Technology Data Exchange (ETDEWEB)

Russo, Paolo [Università di Napoli Federico II, Dipartimento di Fisica, Via Cintia, Naples I-80126 (Italy); INFN Sezione di Napoli, Via Cintia, Naples I-80126 (Italy); Larobina, Michele [Istituto di Biostrutture e Bioimmagini, Consiglio Nazionale delle Ricerche, Via Tommaso De Amicis, 95, Naples I-80145 (Italy); Di Lillo, Francesca [Università di Napoli Federico II, Dipartimento di Fisica, Via Cintia, Naples I-80126 (Italy); INFN Sezione di Napoli, Via Cintia, Naples I-80126 (Italy); Del Vecchio, Silvana [Università di Napoli Federico II, Dipartimento di Scienze Biomediche Avanzate, Via Pansini, 5, Naples I-80131 (Italy); Mettivier, Giovanni, E-mail: mettivier@na.infn.it [Università di Napoli Federico II, Dipartimento di Fisica, Via Cintia, Naples I-80126 (Italy); INFN Sezione di Napoli, Via Cintia, Naples I-80126 (Italy)

2016-02-11

In the field of nuclear medicine imaging, breast imaging for cancer diagnosis is still mainly based on 2D imaging techniques. Three-dimensional tomographic imaging with whole-body PET or SPECT scanners, when used for imaging the breast, has performance limits in terms of spatial resolution and sensitivity, which can be overcome only with a dedicated instrumentation. However, only few hybrid imaging systems for PET/CT or SPECT/CT dedicated to the breast have been developed in the last decade, providing complementary functional and anatomical information on normal breast tissue and lesions. These systems are still under development and clinical trials on just few patients have been reported; no commercial dedicated breast PET/CT or SPECT/CT is available. This paper reviews combined dedicated breast PET/CT and SPECT/CT scanners described in the recent literature, with focus on their technological aspects.

Interpretative intra- and interobserver reproducibility of Stress/Rest 99m Tc-steamboat's myocardial perfusion SPECT using semi quantitative 20-segment model

International Nuclear Information System (INIS)

Fazeli, M.; Firoozi, F.

2002-01-01

It well established that myocardial perfusion SPECT with 201 T L or 99 mTc-se sta mi bi play an important role diagnosis and risk assessment in patients with known or suspected coronary artery disease. Both quantitative and qualitative methods are available for interpretation of images. The use of a semi quantitative scoring system in which each of 20 segments is scored according to a five-point scheme provides an approach to interpretation that is more systematic and reproducible than simple qualitative evaluation. Only a limited number of studies have dealt with the interpretive observer reproducibility of 99 mTc-steamboat's myocardial perfusion imaging. The aim of this study was to assess the intra-and inter observer variability of semi quantitative SPECT performed with this technique. Among 789 patients that underwent myocardial perfusion SPECT during last year 80 patients finally need to coronary angiography as gold standard. In this group of patients a semi quantitative visual interpretation was carried out using short axis and vertical long-axis myocardial tomograms and a 20-segments model. These segments we reassigned on six evenly spaced regions in the apical, mid-ventricular, and basal short-axis view and two apical segments on the mid-ventricular long-axis slice. Uptake in each segment was graded on a 5-point scale (0=normal, 1=equivocal, 2=moderate, 3=severe, 4=absence of uptake). The steamboat's images was interpreted separately w ice by two observers without knowledge of each other's findings or results of angiography. A SPECT study was judged abnormal if there were two or more segments with a stress score equal or more than 2. We con eluded that semi-quantitative visual analysis is a simple and reproducible method of interpretation

Relationship Between Coronary Contrast-Flow Quantitative Flow Ratio and Myocardial Ischemia Assessed by SPECT MPI.

Science.gov (United States)

Smit, Jeff M; Koning, Gerhard; van Rosendael, Alexander R; Dibbets-Schneider, Petra; Mertens, Bart J; Jukema, J Wouter; Delgado, Victoria; Reiber, Johan H C; Bax, Jeroen J; Scholte, Arthur J

2017-10-01

A new method has been developed to calculate fractional flow reserve (FFR) from invasive coronary angiography, the so-called "contrast-flow quantitative flow ratio (cQFR)". Recently, cQFR was compared to invasive FFR in intermediate coronary lesions showing an overall diagnostic accuracy of 85%. The purpose of this study was to investigate the relationship between cQFR and myocardial ischemia assessed by single-photon emission computed tomography myocardial perfusion imaging (SPECT MPI). Patients who underwent SPECT MPI and coronary angiography within 3 months were included. The cQFR computation was performed offline, using dedicated software. The cQFR computation was based on 3-dimensional quantitative coronary angiography (QCA) and computational fluid dynamics. The standard 17-segment model was used to determine the vascular territories. Myocardial ischemia was defined as a summed difference score ≥2 in a vascular territory. A cQFR of ≤0.80 was considered abnormal. Two hundred and twenty-four coronary arteries were analysed in 85 patients. Overall accuracy of cQFR to detect ischemia on SPECT MPI was 90%. In multivariable analysis, cQFR was independently associated with ischemia on SPECT MPI (OR per 0.01 decrease of cQFR: 1.10; 95% CI 1.04-1.18, p = 0.002), whereas clinical and QCA parameters were not. Furthermore, cQFR showed incremental value for the detection of ischemia compared to clinical and QCA parameters (global chi square 48.7 to 62.6; p relationship between cQFR and SPECT MPI was found. cQFR was independently associated with ischemia on SPECT MPI and showed incremental value to detect ischemia compared to clinical and QCA parameters.

Utility of Quantitative Tc-MAA SPECT/CT for yttrium-Labelled Microsphere Treatment Planning: Calculating Vascularized Hepatic Volume and Dosimetric Approach.

Science.gov (United States)

Garin, Etienne; Rolland, Yan; Lenoir, Laurence; Pracht, Marc; Mesbah, Habiba; Porée, Philippe; Laffont, Sophie; Clement, Bruno; Raoul, Jean-Luc; Boucher, Eveline

2011-01-01

Objectives. The aim of this study was to assess the effectiveness of SPECT/CT for volume measurements and to report a case illustrating the major impact of SPECT/CT in calculating the vascularized liver volume and dosimetry prior to injecting radiolabelled yttrium-90 microspheres (Therasphere). Materials and Methods. This was a phantom study, involving volume measurements carried out by two operators using SPECT and SPECT/CT images. The percentage of error for each method was calculated, and interobserver reproducibility was evaluated. A treatment using Therasphere was planned in a patient with three hepatic arteries, and the quantitative analysis of SPECT/CT for this patient is provided. Results. SPECT/CT volume measurements proved to be accurate (mean error Therasphere used. Conclusions. MAA SPECT/CT is accurate for vascularized liver volume measurements, providing a valuable contribution to the therapeutic planning of patients with complex hepatic vascularization.

Brain Perfusion SPECT Imaging in Sturge - Weber Syndrome : Comparison with MR Imaging

International Nuclear Information System (INIS)

Ryu, Jin Sook; Choi, Yun Young; Moon, Dae Hyuk; Yang, Seoung Oh; Ko, Tae Sung; Yoo, Shi Joon; Lee, Hee Kyung

1996-01-01

The purpose of this study was evaluate the characteristic perfusion changes in patients with Sturge-Weber syndrome by comparison of the findings of brain MR images and perfusion SPECT images. 99m Tc-HMPAO or 99m Tc-ECD interictal brain SPECTs were performed on 5 pediatric patients with Struge-Weber syndrome within 2 weeks after MR imaging. Brain SPECTs of three patients without calcification showed diminished perfusion in the affected area on MR image. A 3 month-old patient without brain atrophy or calcification demonstrated paradoxical hyperperfusion in the affected hemisphere, and follow-up perfusion SPECT revealed decreased perfusion in the same area. The other patient with advanced calcified lesion and atrophy on MR image showed diffusely decreased perfusion in the affected hemisphere, but a focal area of increased perfusion was also noted in the ipsilateral temporal lobe on SPECT. In conclusion, brain perfusion of the affected area of Sturge-Weber syndrome patients was usually diminished, but early or advanced patients may show paradoxical diffuse or focal hyperperfusion in the affected hemisphere. Further studies are needed for better understanding of these perfusion changes and pathophysiology of Struge-Weber syndrome.

A CT-based method for fully quantitative TI SPECT

International Nuclear Information System (INIS)

Willowson, Kathy; Bailey, Dale; Baldock, Clive

2009-01-01

Full text: Objectives: To develop and validate a method for quantitative 2 0 l TI SPECT data based on corrections derived from X-ray CT data, and to apply the method in the clinic for quantitative determination of recurrence of brain tumours. Method: A previously developed method for achieving quantitative SPECT with 9 9 m Tc based on corrections derived from xray CT data was extended to apply to 2 0 l Tl. Experimental validation was performed on a cylindrical phantom by comparing known injected activity and measured concentration to quantitative calculations. Further evaluation was performed on a RSI Striatal Brain Phantom containing three 'lesions' with activity to background ratios of 1: 1, 1.5: I and 2: I. The method was subsequently applied to a series of scans from patients with suspected recurrence of brain tumours (principally glioma) to determine an SUV-like measure (Standardised Uptake Value). Results: The total activity and concentration in the phantom were calculated to within 3% and I % of the true values, respectively. The calculated values for the concentration of activity in the background and corresponding lesions of the brain phantom (in increasing ratios) were found to be within 2%,10%,1% and 2%, respectively, of the true concentrations. Patient studies showed that an initial SUV greater than 1.5 corresponded to a 56% mortality rate in the first 12 months, as opposed to a 14% mortality rate for those with a SUV less than 1.5. Conclusion: The quantitative technique produces accurate results for the radionuclide 2 0 l Tl. Initial investigation in clinical brain SPECT suggests correlation between quantitative uptake and survival.

Attenuation correction of myocardial SPECT images with X-ray CT. Effects of registration errors between X-ray CT and SPECT

International Nuclear Information System (INIS)

Takahashi, Yasuyuki; Murase, Kenya; Mochizuki, Teruhito; Motomura, Nobutoku

2002-01-01

Attenuation correction with an X-ray CT image is a new method to correct attenuation on SPECT imaging, but the effect of the registration errors between CT and SPECT images is unclear. In this study, we investigated the effects of the registration errors on myocardial SPECT, analyzing data from a phantom and a human volunteer. Registerion (fusion) of the X-ray CT and SPECT images was done with standard packaged software in three dimensional fashion, by using linked transaxial, coronal and sagittal images. In the phantom study, and X-ray CT image was shifted 1 to 3 pixels on the x, y and z axes, and rotated 6 degrees clockwise. Attenuation correction maps generated from each misaligned X-ray CT image were used to reconstruct misaligned SPECT images of the phantom filled with 201 Tl. In a human volunteer, X-ray CT was acquired in different conditions (during inspiration vs. expiration). CT values were transferred to an attenuation constant by using straight lines; an attenuation constant of 0/cm in the air (CT value=-1,000 HU) and that of 0.150/cm in water (CT value=0 HU). For comparison, attenuation correction with transmission CT (TCT) data and an external γ-ray source ( 99m Tc) was also applied to reconstruct SPECT images. Simulated breast attenuation with a breast attachment, and inferior wall attenuation were properly corrected by means of the attenuation correction map generated from X-ray CT. As pixel shift increased, deviation of the SPECT images increased in misaligned images in the phantom study. In the human study, SPECT images were affected by the scan conditions of the X-ray CT. Attenuation correction of myocardial SPECT with an X-ray CT image is a simple and potentially beneficial method for clinical use, but accurate registration of the X-ray CT to SPECT image is essential for satisfactory attenuation correction. (author)

Skeletal scintigraphy and SPECT/CT in orthopedic imaging; Knochenszintigrafie und SPECT/CT bei orthopaedischen Fragestellungen

Energy Technology Data Exchange (ETDEWEB)

Klaeser, B.; Walter, M.; Krause, T. [Inselspital Bern (Switzerland). Universitaetsklinik fuer Nuklearmedizin

2011-03-15

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

Myocardial perfusion SPECT imaging in patients with myocardial bridging

International Nuclear Information System (INIS)

Fang Wei; Qiu Hong; Yang Weixian; Wang Feng; He Zuoxiang

2008-01-01

Objective: Stress myocardial perfusion SPECT imaging was used to assess myocardial ischemia in patients with myocardial bridging. Methods: Ninety-six patients with myocardial bridging of the left anterior descending artery documented by coronary angiography were included in this study. All under- went exercise or pharmacological stress myocardial perfusion SPECT assessing myocardial ischemia. None had prior myocardial infarction. One year follow-up by telephone interview was performed in all patients. Results The mean stenotic severity of systolic phase on angiography was (65 ± 19)%. In the SPECT study, 20 of 96 (20.8%) patients showed abnormal perfusion. This percentage was significantly higher than that of stress electrocardiogram (ECG). The higher positive rate of SPECT perfusion images was showed in the group of patients with severe systolic narrowing (≥75%) than that with mild-to-moderate systolic narrowing (50% vs 6.3%, P<0.001). The prevalence of abnormal image was significantly higher in ELDERLY PEOPLE; patients with STT change on rest ECG than in those with normal rest ECG (54.2% vs 9.7%, P<0.001). During follow-up, one patient with abnormal SPECT perfusion image sustained angina and accepted percutaneous coronary intervention, and no cardiac event occurred in patients with normal images. Conclusions: Stress myocardial perfusion SPECT imaging can be used effectively for assessing myocardial ischemia and has potential prognostic value for patients with myocardial bridging. (authors)

Skeletal scintigraphy and SPECT/CT in orthopedic imaging

International Nuclear Information System (INIS)

Klaeser, B.; Walter, M.; Krause, T.

2011-01-01

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

Preclinical imaging characteristics and quantification of Platinum-195m SPECT

Energy Technology Data Exchange (ETDEWEB)

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

2017-08-15

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

Automatic extraction of left ventricle in SPECT myocardial perfusion imaging

International Nuclear Information System (INIS)

Liu Li; Zhao Shujun; Yao Zhiming; Wang Daoyu

1999-01-01

An automatic method of extracting left ventricle from SPECT myocardial perfusion data was introduced. This method was based on the least square analysis of the positions of all short-axis slices pixels from the half sphere-cylinder myocardial model, and used a iterative reconstruction technique to automatically cut off the non-left ventricular tissue from the perfusion images. Thereby, this technique provided the bases for further quantitative analysis

Performance of Myocardial Perfusion Imaging Using Multi-focus Fan Beam Collimator with Resolution Recovery Reconstruction in a Comparison with Conventional SPECT

International Nuclear Information System (INIS)

Matsutomo, Norikazu; Nagaki, Akio; Sasaki, Masayuki

2014-01-01

IQ-SPECT is an advanced high-speed SPECT modality for myocardial perfusion imaging (MPI), which uses a multi-focus fan beam collimator with resolution recovery reconstruction. The aim of this study was to compare IQ-SPECT with conventional SPECT in terms of performance, based on standard clinical protocols. In addition, we examined the concordance between conventional and IQ-SPECT in patients with coronary artery disease (CAD). Fifty-three patients, undergoing rest-gated MPI for the evaluation of known or suspected CAD, were enrolled in this study. In each patient, conventional SPECT ( 99m Tc-tetrofosmin, 9.6 min and 201 Tl, 12.9 min) was performed, immediately followed by IQ-SPECT, using a short acquisition time (4.3 min for 99m Tc-tetrofosmin and 6.2 min for 201 Tl). A quantitative analysis was performed on an MPI polar map, using a 20-segment model of the left ventricle. An automated analysis by gated SPECT was carried out to determine the left ventricular volume and function including end-diastolic volume (EDV), end-systolic volume (ESV), and left ventricular ejection fraction (LVEF). The degree of concordance between conventional SPECT and IQ-SPECT images was evaluated according to linear regression and Bland-Altman analyses. The segmental percent uptake exhibited a significant correlation between IQ-SPECT and conventional SPECT (P<0.05). The mean differences in 99m Tc-tetrofosmin studies were 1.1±6.6% (apex), 2.8±5.7% (anterior wall), 2.9±6.2% (septal wall), 4.9±6.7% (lateral wall), and 1.8±5.6% (inferior wall). Meanwhile, regarding the 201 Tl-SPECT studies, these values were 1.6±6.9%, 2.0±6.6%, 2.1±5.9%, 3.3±7.2%, and 2.4±5.8%, respectively. Although the mean LVEF in IQ-SPECT tended to be higher than that observed in conventional SPECT (conventional SPECT=64.8±11.8% and IQ-SPECT=68.3±12.1% for 99m Tc-tetrofosmin; conventional SPECT= 56.0±11.7% and IQ-SPECT=61.5±12.2% for 201 Tl), quantitative parameters were not significantly different between

Pharmacologic stress-induced stunning: evaluation with quantitative gated SPECT

International Nuclear Information System (INIS)

Chun, K. A.; Cho, I. H.; Won, K. J.; Lee, H. W.

2000-01-01

The after-effect of pharmacologic stress (adenosine) on left ventricular (LV) function, end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (LVEF) were evaluated after pharmacologic stress with Tl-201 and 99m Tc-MIBI SPECT using an automated program in 153 subjects. The subjects were grouped as follows: 1) Tl-201 group (n=35, male 18, female 17, mean age: 58 years); normal scan (n=24), ischemia (n=8) and infarction (n=3). 2) 99m Tc-MIBI group (n=118, male 60, female 58, mean age: 62 years); normal scan (n=73), ischemia (n=20) and infarction (n=25) based on the interpretation of perfusion images. All patients were in sinus rhythm during the study. 1)Tl-201 group; In patients with ischemia (the mean time interval between injection and acquisition is 12.3 min), post-stress LVEF was significantly depressed after adenosine infusion (51.2 ± 6.3% vs 59.8± 8.2%, p 99m Tc-MIBI group; In patients with ischemia (the mean time interval between injection and acquisition is 80 min), post-stress LVEF was significantly depressed after adenosine infusion (p<0.001) and ΔLVEF was 5.1%. Eight patients (40%) showed an increase in LVEF greater than 5% from poststress to rest. Poststress ESV (37.1±17.3 ml) was significantly higher than ESV (31.3±15.5 ml, p<0.001) at rest, but no significant difference in EDV. These results showed that pharmacologic stress induced stunning is well noted in the early quantitative gated SPECT in ischemic patients and also observed in the delayed gated SPECT, even though the rate of stunning is less than the early SPECT

Fusion of SPECT/TC images: Usefulness and benefits in degenerative spinal cord pathology

International Nuclear Information System (INIS)

Ocampo, Monica; Ucros, Gonzalo; Bermudez, Sonia; Morillo, Anibal; Rodriguez, Andres

2005-01-01

The objectives are to compare CT and SPECT bone scintigraphy evaluated independently with SPECT-CT fusion images in patients with known degenerative spinal pathology. To demonstrate the clinical usefulness of CT and SPECT fusion images. Materials and methods: Thirty-one patients with suspected degenerative spinal disease were evaluated with thin-slice, non-angled helical CT and bone scintigrams with single photon emission computed tomography (SPECT), both with multiplanar reconstructions within a 24-hour period After independent evaluation by a nuclear medicine specialist and a radiologist, multimodality image fusion software was used to merge the CT and SPECT studies and a final consensus interpretation of the combined images was obtained. Results: Thirty-two SPECT bone scintigraphy images, helical CT studies and SPECT-CT fusion images were obtained for 31 patients with degenerative spinal disease. The results of the bone scintigraphy and CT scans were in agreement in 17 pairs of studies (53.12%). In these studies image fusion did not provide additional information on the location or extension of the lesions. In 11 of the study pairs (34.2%), the information obtained was not in agreement between scintigraphy and CT studies: CT images demonstrated several abnormalities, whereas the SPECT images showed only one dominant lesion, or the SPECT images did not provide enough information for anatomical localization. In these cases image fusion helped establish the precise localization of the most clinically significant lesion, which matched the lesion with the greatest uptake. In 4 studies (12.5%) the CT and SPECT images were not in agreement: CT and SPECT images showed different information (normal scintigraphy, abnormal CT), thus leading to inconclusive fusion images. Conclusion: The use of CT-SPECT fusion images in degenerative spinal disease allows for the integration of anatomic detail with physiologic and functional information. CT-SPECT fusion improves the

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

International Nuclear Information System (INIS)

Uemura, K.; Toyama, H.; Miyamoto, T.; Yoshikawa, K.; Mori, Y.

2002-01-01

found to be possible to evaluate the therapeutic gain of heavy particle therapy sequentially by using the same ROI. Conclusion: This method is useful for evaluating the therapeutic gain of heavy particle therapy performed on patients with lung cancer quantitatively and sequentially. Registration of chest SPECT, PET and/or X-ray CT images by using AMIR method got good result for all of the registrations

Evaluating performance of a pixel array semiconductor SPECT system for small animal imaging

International Nuclear Information System (INIS)

Kubo, Naoki; Zhao, Songji; Fujiki, Yutaka

2005-01-01

Small animal imaging has recently been focused on basic nuclear medicine. We have designed and built a small animal SPECT imaging system using a semiconductor camera and a newly designed collimator. We assess the performance of this system for small object imaging. We employed an MGC 1500 (Acrorad Co.) camera including a CdTe semiconductor. The pixel size was 1.4 mm/pixel. We designed and produced a parallel-hole collimator with 20-mm hole length. Our SPECT system consisted of a semiconductor camera with the subject holder set on an electric rotating stage controlled by a computer. We compared this system with a conventional small animal SPECT system comprising a SPECT-2000H scanner with four Anger type cameras and pinhole collimators. The count rate linearity for estimation of the scatter was evaluated for a pie-chart phantom containing different concentrations of 99m Tc. We measured the full width half maximum (FWHM) of the 99m Tc SPECT line source along with scatter. The system volume sensitivity was examined using a flood source phantom which was 35 mm long with a 32-mm inside diameter. Additionally, an in vivo myocardial perfusion SPECT study was performed with a rat. With regards to energy resolution, the semiconductor camera (5.6%) was superior to the conventional Anger type camera (9.8%). In the count rate linearity evaluation, the regression lines of the SPECT values were y=0.019x+0.031 (r 2 =0.999) for our system and y=0.018x+0.060 (r 2 =0.997) for the conventional system. Thus, the scatter count using the semiconductor camera was less than that using the conventional camera. FWHMs of our system and the conventional system were 2.9±0.1 and 2.0±0.1 mm, respectively. Moreover, the system volume sensitivity of our system [0.51 kcps/(MBq/ml)/cm] was superior to that of the conventional system [0.44 kcps/(MBq/ml)/cm]. Our system provided clear images of the rat myocardium, sufficient for practical use in small animal imaging. Our SPECT system, utilizing a

Methods of evaluating SPECT images. The usefulness of the Matsuda`s method by the Patlak plot method in children

Energy Technology Data Exchange (ETDEWEB)

Takaishi, Yasuko [Nippon Medical School, Tokyo (Japan); Hashimoto, Kiyoshi; Fujino, Osamu [and others

1998-11-01

Single photon emission computed tomography (SPECT) is a tool to study cerebral blood flow (CBF) kinetics. There are three methods of evaluating SPECT images: visual, semi-quantitative (evaluation of the radioactivity ratio of the cerebral region to the cerebellum (R/CE) or to the thalamus (R/TH)) and quantitative (Matsuda`s method by Patlak plot method using {sup 99m}Tc-hexamethylpropylene amine oxime radionuclide angiography). We evaluated SPECT images by the quantitative method in 14 patients with neurological disorders and examined the correlation of the results to those obtained by the semi-quantitative method. There was no significant correlation between the R/CE or R/TH ratio and regional CBF except two regions. The evaluation by the semi-quantitative method may have been inappropriate, probably because the cerebellar or thalamic blood flow was not constant in each case. Evaluation by the quantitative method, on the other hand, seemed to be useful not only for the comparison of CBF among normal subjects, but also in the demonstration of progressive changes of CBF in the same case. The Matsuda`s method by the Patlak plot method is suitable for examination of children, since it dose not require aortic blood sampling. (author)

Imaging of gene expression in live pancreatic islet cell lines using dual-isotope SPECT.

Science.gov (United States)

Tai, Joo Ho; Nguyen, Binh; Wells, R Glenn; Kovacs, Michael S; McGirr, Rebecca; Prato, Frank S; Morgan, Timothy G; Dhanvantari, Savita

2008-01-01

We are combining nuclear medicine with molecular biology to establish a sensitive, quantitative, and tomographic method with which to detect gene expression in pancreatic islet cells in vivo. Dual-isotope SPECT can be used to image multiple molecular events simultaneously, and coregistration of SPECT and CT images enables visualization of reporter gene expression in the correct anatomic context. We have engineered pancreatic islet cell lines for imaging with SPECT/CT after transplantation under the kidney capsule. INS-1 832/13 and alphaTC1-6 cells were stably transfected with a herpes simplex virus type 1-thymidine kinase-green fluorescent protein (HSV1-thymidine kinase-GFP) fusion construct (tkgfp). After clonal selection, radiolabel uptake was determined by incubation with 5-(131)I-iodo-1-(2-deoxy-2-fluoro-beta-d-arabinofuranosyl)uracil ((131)I-FIAU) (alphaTC1-6 cells) or (123)I-FIAU (INS-1 832/13 cells). For the first set of in vivo experiments, SPECT was conducted after alphaTC1-6/tkgfp cells had been labeled with either (131)I-FIAU or (111)In-tropolone and transplanted under the left kidney capsule of CD1 mice. Reconstructed SPECT images were coregistered to CT. In a second study using simultaneous acquisition dual-isotope SPECT, INS-1 832/13 clone 9 cells were labeled with (111)In-tropolone before transplantation. Mice were then systemically administered (123)I-FIAU and data for both (131)I and (111)In were acquired simultaneously. alphaTC1-6/tkgfp cells showed a 15-fold greater uptake of (131)I-FIAU, and INS-1/tkgfp cells showed a 12-fold greater uptake of (123)I-FIAU, compared with that of wild-type cells. After transplantation under the kidney capsule, both reporter gene expression and location of cells could be visualized in vivo with dual-isotope SPECT. Immunohistochemistry confirmed the presence of glucagon- and insulin-positive cells at the site of transplantation. Dual-isotope SPECT is a promising method to detect gene expression in and location of

Relationship between coronary contrast-flow quantitative flow ratio and myocardial ischemia assessed by SPECT MPI

Energy Technology Data Exchange (ETDEWEB)

Smit, Jeff M.; Rosendael, Alexander R. van; Jukema, J.W.; Delgado, Victoria; Bax, Jeroen J.; Scholte, Arthur J. [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands); Koning, Gerhard [Medis Medical Imaging Systems B.V., Leiden (Netherlands); Dibbets-Schneider, Petra [Leiden University Medical Center, Department of Nuclear Medicine, Leiden (Netherlands); Mertens, Bart J. [Leiden University Medical Center, Department of Medical Statistics, Leiden (Netherlands); Reiber, Johan H.C. [Medis Medical Imaging Systems B.V., Leiden (Netherlands); Leiden University Medical Center, Department of Radiology, Leiden (Netherlands)

2017-10-15

A new method has been developed to calculate fractional flow reserve (FFR) from invasive coronary angiography, the so-called ''contrast-flow quantitative flow ratio (cQFR)''. Recently, cQFR was compared to invasive FFR in intermediate coronary lesions showing an overall diagnostic accuracy of 85%. The purpose of this study was to investigate the relationship between cQFR and myocardial ischemia assessed by single-photon emission computed tomography myocardial perfusion imaging (SPECT MPI). Patients who underwent SPECT MPI and coronary angiography within 3 months were included. The cQFR computation was performed offline, using dedicated software. The cQFR computation was based on 3-dimensional quantitative coronary angiography (QCA) and computational fluid dynamics. The standard 17-segment model was used to determine the vascular territories. Myocardial ischemia was defined as a summed difference score ≥2 in a vascular territory. A cQFR of ≤0.80 was considered abnormal. Two hundred and twenty-four coronary arteries were analysed in 85 patients. Overall accuracy of cQFR to detect ischemia on SPECT MPI was 90%. In multivariable analysis, cQFR was independently associated with ischemia on SPECT MPI (OR per 0.01 decrease of cQFR: 1.10; 95% CI 1.04-1.18, p = 0.002), whereas clinical and QCA parameters were not. Furthermore, cQFR showed incremental value for the detection of ischemia compared to clinical and QCA parameters (global chi square 48.7 to 62.6; p <0.001). A good relationship between cQFR and SPECT MPI was found. cQFR was independently associated with ischemia on SPECT MPI and showed incremental value to detect ischemia compared to clinical and QCA parameters. (orig.)

Multimodality imaging: transfer and fusion of SPECT and MRI data

International Nuclear Information System (INIS)

Knesaurek, K.

1994-01-01

Image fusion is a technique which offers the best of both worlds. It unites the two basic types of medical images: functional body images(PET or SPECT scans), which provide physiological information, and structural images (CT or MRI), which provide an anatomic map of the body. Control-point based registration technique was developed and used. Tc-99m point sources were used as external markers in SPECT studies while, for MRI and CT imaging only anatomic landmarks were used as a control points. The MRI images were acquired on GE Signa 1.2 system and CT data on a GE 9800 scanner. SPECT studies were performed 1h after intravenous injection of the 740 MBq of the Tc-99m-HMPAO on the triple-headed TRIONIX gamma camera. B-spline and bilinear interpolation were used for the rotation, scaling and translation of the images. In the process of creation of a single composite image, in order to retain information from the individual images, MRI (or CT) image was scaled to one color range and a SPECT image to another. In some situations the MRI image was kept black-and-white while the SPECT image was pasted on top of it in 'opaque' mode. Most errors which propagate through the matching process are due to sample size, imperfection of the acquisition system, noise and interpolations used. Accuracy of the registration was investigated by SPECT-CT study performed on a phantom study. The results has shown that accuracy of the matching process is better, or at worse, equal to 2 mm. (author)

Sequential SPECT/CT imaging starting with stress SPECT in patients with left bundle branch block suspected for coronary artery disease

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Engbers, Elsemiek M.; Mouden, Mohamed [Isala, Department of Cardiology, Zwolle (Netherlands); Isala, Department of Nuclear Medicine, Zwolle (Netherlands); Timmer, Jorik R.; Ottervanger, Jan Paul [Isala, Department of Cardiology, Zwolle (Netherlands); Knollema, Siert; Jager, Pieter L. [Isala, Department of Nuclear Medicine, Zwolle (Netherlands)

2017-01-15

To investigate the impact of left bundle branch block (LBBB) on sequential single photon emission computed tomography (SPECT)/ CT imaging starting with stress-first SPECT. Consecutive symptomatic low- to intermediate-risk patients without a history of coronary artery disease (CAD) referred for SPECT/CT were included from an observational registry. If stress SPECT was abnormal, additional rest SPECT and, if feasible, coronary CT angiography (CCTA) were acquired. Of the 5,018 patients, 218 (4.3 %) demonstrated LBBB. Patients with LBBB were slightly older than patients without LBBB (65±12 vs. 61±11 years, p<0.001). Stress SPECT was more frequently abnormal in patients with LBBB (82 % vs. 46 %, p<0.001). After reviewing stress and rest images, SPECT was normal in 43 % of the patients with LBBB, compared to 77 % of the patients without LBBB (p<0.001). Sixty-four of the 124 patients with LBBB and abnormal stress-rest SPECT underwent CCTA (52 %), which could exclude obstructive CAD in 46 of the patients (72 %). Sequential SPECT/CT imaging starting with stress SPECT is not the optimal imaging protocol in patients with LBBB, as the majority of these patients have potentially false-positive stress SPECT. First-line testing using CCTA may be more appropriate in low- to intermediate-risk patients with LBBB. (orig.)

Filters in 2D and 3D Cardiac SPECT Image Processing

Directory of Open Access Journals (Sweden)

Maria Lyra

2014-01-01

Full Text Available Nuclear cardiac imaging is a noninvasive, sensitive method providing information on cardiac structure and physiology. Single photon emission tomography (SPECT evaluates myocardial perfusion, viability, and function and is widely used in clinical routine. The quality of the tomographic image is a key for accurate diagnosis. Image filtering, a mathematical processing, compensates for loss of detail in an image while reducing image noise, and it can improve the image resolution and limit the degradation of the image. SPECT images are then reconstructed, either by filter back projection (FBP analytical technique or iteratively, by algebraic methods. The aim of this study is to review filters in cardiac 2D, 3D, and 4D SPECT applications and how these affect the image quality mirroring the diagnostic accuracy of SPECT images. Several filters, including the Hanning, Butterworth, and Parzen filters, were evaluated in combination with the two reconstruction methods as well as with a specified MatLab program. Results showed that for both 3D and 4D cardiac SPECT the Butterworth filter, for different critical frequencies and orders, produced the best results. Between the two reconstruction methods, the iterative one might be more appropriate for cardiac SPECT, since it improves lesion detectability due to the significant improvement of image contrast.

Comparison of 99mTc-MDP SPECT qualitative vs quantitative results in patients with suspected condylar hyperplasia.

Science.gov (United States)

López Buitrago, D F; Ruiz Botero, J; Corral, C M; Carmona, A R; Sabogal, A

To compare qualitative vs quantitative results of Single Photon Emission Computerised Tomography (SPECT), calculated from percentage of 99m Tc-MDP (methylene diphosphonate) uptake, in condyles of patients with a presumptive clinical diagnosis of condylar hyperplasia. A retrospective, descriptive study was conducted on the 99m Tc-MDP SPECT bone scintigraphy reports from 51 patients, with clinical impression of facial asymmetry related to condylar hyperplasia referred by their specialist in orthodontics or maxillofacial surgery, to a nuclear medicine department in order to take this type of test. Quantitative data from 99m Tc-MDP condylar uptake of each were obtained and compared with qualitative image interpretation reported by a nuclear medicine expert. The concordances between the 51 qualitative and quantitative reports results was established. The total sample included 32 women (63%) and 19 men (37%). The patient age range was 13-45 years (21±8 years). According to qualitative reports, 19 patients were positive for right side condylar hyperplasia, 12 for left side condylar hyperplasia, with 8 bilateral, and 12 negative. The quantitative reports diagnosed 16 positives for right side condylar hyperplasia, 10 for left side condylar hyperplasia, and 25 negatives. Nuclear medicine images are an important diagnostic tool, but the qualitative interpretation of the images is not as reliable as the quantitative calculation. The agreement between the two types of report is low (39.2%, Kappa=0.13; P>.2). The main limitation of quantitative reports is that they do not register bilateral condylar hyperplasia cases. Copyright © 2017 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

SPECT/CT imaging in general orthopedic practice.

Science.gov (United States)

Scharf, Stephen

2009-09-01

The availability of hybrid devices that combine the latest single-photon emission computed tomography (SPECT) imaging technology with multislice computed tomography (CT) scanning has allowed us to detect subtle, nonspecific abnormalities on bone scans and interpret them as specific focal areas of pathology. Abnormalities in the spine can be separated into those caused by pars fractures, facet joint arthritis, or osteophyte formation on vertebral bodies. Compression fractures can be distinguished from severe degenerative disease, both of which can cause intense activity across the spine on either planar or SPECT imaging. Localizing activity in patients who have had spinal fusion can provide tremendous insight into the causes of therapeutic failures. Infections of the spine now can be diagnosed with gallium SPECT/CT, despite the fact that gallium has long been abandoned because of its failure to detect spine infection on either planar or SPECT imaging. Small focal abnormalities in the feet and ankles can be localized well enough to make specific orthopedic diagnoses on the basis of their location. Moreover, when radiographic imaging provides equivocal or inadequate information, SPECT/CT can provide a road map for further diagnostic studies and has been invaluable in planning surgery. Our ability to localize activity within a bone or at an articular surface has allowed us to distinguish between fractures and joint disease. Increased activity associated with congenital anomalies, such as tarsal coalition and Bertolotti's syndrome have allowed us to understand the pathophysiology of these conditions, to confirm them as the cause of the patient's symptoms, and to provide information that is useful in determining appropriate clinical management. As our experience broadens, SPECT/CT will undoubtedly become an important tool in the evaluation and management of a wider variety of orthopedic patients.

Role of SPECT imaging in symptomatic posterior element lumbar stress injuries

Directory of Open Access Journals (Sweden)

Debnath U

2005-01-01

Full Text Available Background : Diagnosis of stress injuries of spine is very difficult with conventional radiography. Methods : In a observational study, 132 subjects were recruited (between 8 and 38 years of age, who had lumbar spondylolysis or posterior element stress injuries. All these patients underwent clinical examination followed by plain X-rays, planar bone scintigraphy and SPECT (single photon emission computerised tomography. SPECT scans can identify the posterior element lumbar stress injuries earlier than other imaging modalities. As the lesions evolve and the completed spondylolysis becomes chronic, the SPECT scans tend to revert to normal even though healing of the defect has not occurred. The aim of the study was to determine the time lag after which SPECT imaging tends to be negative. We divided the patients into two groups, one SPECT positive group and the other SPECT negative group. Pre treatment background variables such as age, gender, back pain in extension or flexion, sporting activities, time of onset of symptoms, Oswestry Disability Index (ODI were used in a univariate logistic regression model to find the strong predictors of positive SPECT imaging results. Determinants of positivity versus negativity of SPECT were identified by discriminant analysis using multivariate logistic regression. Results : Seventy nine patients had positive SPECT scans whereas 53 patients had negative SPECT scans. Bilateral increased uptake was more common than unilateral uptake. Increased uptake at the L5 lumbar spine was more common (70% in SPECT positive group. Low back pain in extension was significantly more common in SPECT positive subjects. Active sporting individuals had higher probability of having a positive SPECT scan. The mean time lag from the onset of low back pain to SPECT imaging was 7 months in SPECT positive group and 25 months in the SPECT negative group. Multivariate analysis predicted that there is a significant difference in positivity of

Usefulness of CT based SPECT Fusion Image in the lung Disease : Preliminary Study

International Nuclear Information System (INIS)

Park, Hoon Hee; Lyu, Kwang Yeul; Kim, Tae Hyung; Shin, Ji Yun

2012-01-01

Recently, SPECT/CT system has been applied to many diseases, however, the application is not extensively applied at pulmonary disease. Especially, in case that, the pulmonary embolisms suspect at the CT images, SPECT is performed. For the accurate diagnosis, SPECT/CT tests are subsequently undergoing. However, without SPECT/CT, there are some limitations to apply these procedures. With SPECT/CT, although, most of the examination performed after CT. Moreover, such a test procedures generate unnecessary dual irradiation problem to the patient. In this study, we evaluated the amount of unnecessary irradiation, and the usefulness of fusion images of pulmonary disease, which independently acquired from SPECT and CT. Using NEMA PhantomTM (NU2-2001), SPECT and CT scan were performed for fusion images. From June 2011 to September 2010, 10 patients who didn't have other personal history, except lung disease were selected (male: 7, female: 3, mean age: 65.3±12.7). In both clinical patient and phantom data, the fusion images scored higher than SPECT and CT images. The fusion images, which is combined with pulmonary vessel images from CT and functional images from SPECT, can increase the detection possibility in detecting pulmonary embolism in the resin of lung parenchyma. It is sure that performing SPECT and CT in integral SPECT/CT system were better. However, we believe this protocol can give more informative data to have more accurate diagnosis in the hospital without integral SPECT/CT system.

Usefulness of quantitative SPECT in unilateral temporomandibular joint disorder: correlation with signs and symptoms

International Nuclear Information System (INIS)

Kim, Ho Sung; Jeong, Jong Cheol; Kim, Keon Jung; Choi, Jae Sun; Sung, Dae Kyung; Lee, Gye Huyk; Kim, Jong Ho

1998-01-01

The aims of this study was to compare the diagnostic accuracy of Conventional Radiography (CR). Radionuclide Angiography (RNA). Planar Scintigraphy (PS) and Single Photon Emission Computed Tomography (SPECT) for the evaluation of temporomandibular joint (TMJ) disorder; and to show whether technetium-99m-MDP uptake on quantitative SPECT correlated with the symptom and/or signs. Three Phase Bone Scintigraphy (TPBS) and SPECT of both TMJ were performed in 51 patients (M : F = 10 : 41 mean age= 30.4 :28.6, respectively) with unilateral TMJ disorder after an intravenous injection of 25 mCi (925 MBq) of 99mTc-MDP. Data were analyzed by creating three regions of interest (ROIs) over designated areas both on the PS and SPECT: Lesion (L). Non-lesion(NL) which is contralateral to L and Background (BG). L/ NL and L/BG (=[(L-BG)/500,000] x 100 (%)] ratios were calculated for each patients. L/NL ratios on SPECT were compared according to the symptom/signs or not. There was a fair correlation of L/N values between three slice-and seven slice-added SPECT images (r=0.5124, p=0.006, y=0.5588 + 0.5414X). The percentages of symptoms or signs were: pain (76.5%), mouth opening limitation (49.0%), joint sound (39.2%), discomfort (43.1%), headache(27.5%), neck stiffness (21.6%), closed lock (5.9%) / tenderness (47.1%), joint click (54.9%) and limitation of maximum mouth opening (45.1%). The Sensitive of SPECT(86.3%) was better than PS(66.7%), RNA(27.5%), and CR(26.3%). According to the presence of symptom/sign or not, comparative analysis of L/NL ratios on SPECT showed a fair correlation in pain (1.16 : 1.11) mouth opening limitation (1.21 : 1.09), joint sound (1.19 : 1.08), discomfort (1.22 : 1.09), headache (1.19: 1.13), tenderness (1.16 : 1.14) and limitation of maximum mouth opening (1.16 : 1.13), but little correlation in neck stiffness (1.12 : 1.15), closed lock (1.06 : 1.15), dislocation (1.08 : 1.15) joint click (1.12 : 1.18). In conclusion, quantitative SPECT is the noninvasive

Evaluation and comparison of quantitative and qualitative effects of scattering in air and water media in planar and SPECT imaging

International Nuclear Information System (INIS)

Saeed Sarkar; Akram Abehesht

2004-01-01

In this research the scatter fraction (%SF) in air and water media in both planar and tomographic imaging was evaluated in order to find the differences and assist the nuclear medicine specialists in interpreting the images.Two small Perspex cylinders of equal dimensions, diameter = 5 cm and height = 5 cm, with an angle of 1200 relative to each other was fixed at the bottom of a 22 cm diameter and 26 cm height Perspex cylinder to make a scattering phantom. One of the cylinders was filled with water representing soft tissue while the other one was left empty (air). The big cylinder was filled with water up to the upper level of small cylinders. 2.5 mCi of 99m Tc was mixed uniformly with the water in the big cylinder. Both planar and tomographic images of the phantom were obtained by a single head SPECT system with %20 energy windows. %SF is defined as %SF = (cold/hot) where, cold and hot are the number of counts in ROIs of each small cold cylinder and big hot cylinder respectively. ROIs selected around the image of each cylinder were equal to the exact size of the objects. In planar image the %SF was found to be %3.24±0.03 and % 3.23±0.03 in air and water respectively. On the other hand the %SF in SPECT images were %6.12±0.05 and %4.47±0.04 in air and water respectively. In planar image no difference is seen in %SF between small cylinders containing air and water whereas in SPECT image the %SF in air cylinder is %27 more than the water cylinder. This has caused more blurred edges for the image of air cylinder. Lower %SF in the small water cylinder may be caused by absorption of scattered events in the water medium. The %SF in SPECT is almost twice the planar imaging for water medium, whereas on the average the %SF in planar imaging is almost %60 of the SPECT. These differences account for better contrast and sharper edges of small cold cylinders in planar imaging. (authors)

Clinical applications of SPECT/CT in imaging the extremities

International Nuclear Information System (INIS)

Huellner, Martin W.; Strobel, Klaus

2014-01-01

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

Clinical applications of SPECT/CT in imaging the extremities

Energy Technology Data Exchange (ETDEWEB)

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

2014-05-15

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

Brain lesion analysis using three-dimensional SPECT imaging

International Nuclear Information System (INIS)

Shibata, Iekado; Onagi, Atsuo; Kuroki, Takao

1995-01-01

A three-headed gamma camera (PRISM 3000) is capable to scan the protocol of early dynamic SPECT and to analyze two radioisotopes at the same time. We have framed three-dimensional brain SPECT images for several brain diseases by using the Application Visualization System (AVS). We carried out volume measurements in brain tumors and/or AVMs by applying this methodology. Thallium-201 and/or 123I-IMP were used for brain SPECT imaging. The dynamic scan protocol was changed in accordance with the given disease. The protocol for brain tumors was derived from a preliminary comparative study with thallium-201 and 123I-IMP that had suggested a disparity in the detection of brain tumors and the differentiation between tumor tissue and normal brain. The three-dimension SPECT image represented the brain tumor or AVM in a striking fashion, and the changes with respect to tumor or AVM after radiosurgery or embolization were understood readily. (author)

Study of regional cerebral blood flow SPECT imaging for sudden sensorineural deafness

International Nuclear Information System (INIS)

Xie Changhui; Kui Xixiao; Xiong Qibin; Wen Hui; Xie Jiabiao

1998-01-01

Purpose: To study the clinical value of regional cerebral blood flow (rCBF) SPECT imaging for sudden sensorineural deafness (SSD). Methods: 10 normal persons, 19 conductive deafness and 31 SSD patients were examined by rCBF SPECT imaging, and compared with X CT at the same time. All SSD patients were followed up for 6∼12 months with repeated rCBF SPECT imaging. Results: 1) The radioactivity of diseased and normal horizontal temporal gyrus ratio (T/NT) in SSD patients was the lowest among three groups (P < 0.01). 2) The sensitivity (80.6%) and accurate rate (88.3%) of rCBF SPECT imaging in SSD patients were much higher than those of CT (3.2% and 50%, P < 0.01). 3) There was a significant correlation between degree of deafness and T/NT in SSD patients. 4) Good prognosis of SSD patients with normal rCBF SPECT was found. 5) The rCBF SPECT had close concordance between rCBF SPECT imaging and clinical prognosis (84.6%). Conclusions: rCBF SPECT imaging was superior to X CT in diagnosis of SSD and played an important clinical role

Initial Investigation of preclinical integrated SPECT and MR imaging.

Science.gov (United States)

Hamamura, Mark J; Ha, Seunghoon; Roeck, Werner W; Wagenaar, Douglas J; Meier, Dirk; Patt, Bradley E; Nalcioglu, Orhan

2010-02-01

Single-photon emission computed tomography (SPECT) can provide specific functional information while magnetic resonance imaging (MRI) can provide high-spatial resolution anatomical information as well as complementary functional information. In this study, we utilized a dual modality SPECT/MRI (MRSPECT) system to investigate the integration of SPECT and MRI for improved image accuracy. The MRSPECT system consisted of a cadmium-zinc-telluride (CZT) nuclear radiation detector interfaced with a specialized radiofrequency (RF) coil that was placed within a whole-body 4 T MRI system. The importance of proper corrections for non-uniform detector sensitivity and Lorentz force effects was demonstrated. MRI data were utilized for attenuation correction (AC) of the nuclear projection data and optimized Wiener filtering of the SPECT reconstruction for improved image accuracy. Finally, simultaneous dual-imaging of a nude mouse was performed to demonstrated the utility of co-registration for accurate localization of a radioactive source.

Absolute quantitation of myocardial blood flow with {sup 201}Tl and dynamic SPECT in canine: optimisation and validation of kinetic modelling

Energy Technology Data Exchange (ETDEWEB)

Iida, Hidehiro; Kim, Kyeong-Min; Nakazawa, Mayumi; Sohlberg, Antti; Zeniya, Tsutomu; Hayashi, Takuya; Watabe, Hiroshi [National Cardiovascular Center Research Institute, Department of Investigative Radiology, Suita City, Osaka (Japan); Eberl, Stefan [National Cardiovascular Center Research Institute, Department of Investigative Radiology, Suita City, Osaka (Japan); Royal Prince Alfred Hospital, PET and Nuclear Medicine Department, Camperdown, NSW (Australia); Tamura, Yoshikazu [Akita Kumiai General Hospital, Department of Cardiology, Akita City (Japan); Ono, Yukihiko [Akita Research Institute of Brain, Akita City (Japan)

2008-05-15

{sup 201}Tl has been extensively used for myocardial perfusion and viability assessment. Unlike {sup 99m}Tc-labelled agents, such as {sup 99m}Tc-sestamibi and {sup 99m}Tc-tetrofosmine, the regional concentration of {sup 201}Tl varies with time. This study is intended to validate a kinetic modelling approach for in vivo quantitative estimation of regional myocardial blood flow (MBF) and volume of distribution of {sup 201}Tl using dynamic SPECT. Dynamic SPECT was carried out on 20 normal canines after the intravenous administration of {sup 201}Tl using a commercial SPECT system. Seven animals were studied at rest, nine during adenosine infusion, and four after beta-blocker administration. Quantitative images were reconstructed with a previously validated technique, employing OS-EM with attenuation-correction, and transmission-dependent convolution subtraction scatter correction. Measured regional time-activity curves in myocardial segments were fitted to two- and three-compartment models. Regional MBF was defined as the influx rate constant (K{sub 1}) with corrections for the partial volume effect, haematocrit and limited first-pass extraction fraction, and was compared with that determined from radio-labelled microspheres experiments. Regional time-activity curves responded well to pharmacological stress. Quantitative MBF values were higher with adenosine and decreased after beta-blocker compared to a resting condition. MBFs obtained with SPECT (MBF{sub SPECT}) correlated well with the MBF values obtained by the radio-labelled microspheres (MBF{sub MS}) (MBF{sub SPECT} = -0.067 + 1.042 x MBF{sub MS}, p < 0.001). The three-compartment model provided better fit than the two-compartment model, but the difference in MBF values between the two methods was small and could be accounted for with a simple linear regression. Absolute quantitation of regional MBF, for a wide physiological flow range, appears to be feasible using {sup 201}Tl and dynamic SPECT. (orig.)

Problems in the optimum display of SPECT images

International Nuclear Information System (INIS)

Fielding, S.L.

1988-01-01

The instrumentation, computer hardware and software, and the image display system are all very important in the production of diagnostically useful SPECT images. Acquisition and processing parameters are discussed which can affect the quality of SPECT images. Regular quality control of the gamma camera and computer is important to keep the artifacts due to instrumentation to a minimum. The choice of reconstruction method will depend on the statistics in the study. The paper has shown that for high count rate studies, a high pass filter can be used to enhance the reconstructions. For lower count rate studies, pre-filtering is useful and the data can be reconstructed into thicker slices to reduce the effect of image noise. Finally, the optimum display for the images must be chosen, so that the information contained in the SPECT data can be easily perceived by the clinician. (orig.) [de

Complexity and accuracy of image registration methods in SPECT-guided radiation therapy

Energy Technology Data Exchange (ETDEWEB)

Yin, L S; Duzenli, C; Moiseenko, V [Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC, V6T 1Z1 (Canada); Tang, L; Hamarneh, G [Computing Science, Simon Fraser University, 9400 TASC1, Burnaby, BC, V5A 1S6 (Canada); Gill, B [Medical Physics, Vancouver Cancer Centre, BC Cancer Agency, 600 West 10th Ave, Vancouver, BC, V5Z 4E6 (Canada); Celler, A; Shcherbinin, S [Department of Radiology, University of British Columbia, 828 West 10th Ave, Vancouver, BC, V5Z 1L8 (Canada); Fua, T F; Thompson, A; Sheehan, F [Radiation Oncology, Vancouver Cancer Centre, BC Cancer Agency, 600 West 10th Ave, Vancouver, BC, V5Z 4E6 (Canada); Liu, M [Radiation Oncology, Fraser Valley Cancer Centre, BC Cancer Agency, 13750 9th Ave, Surrey, BC, V3V 1Z2 (Canada)], E-mail: lyin@bccancer.bc.ca

2010-01-07

The use of functional imaging in radiotherapy treatment (RT) planning requires accurate co-registration of functional imaging scans to CT scans. We evaluated six methods of image registration for use in SPECT-guided radiotherapy treatment planning. Methods varied in complexity from 3D affine transform based on control points to diffeomorphic demons and level set non-rigid registration. Ten lung cancer patients underwent perfusion SPECT-scans prior to their radiotherapy. CT images from a hybrid SPECT/CT scanner were registered to a planning CT, and then the same transformation was applied to the SPECT images. According to registration evaluation measures computed based on the intensity difference between the registered CT images or based on target registration error, non-rigid registrations provided a higher degree of accuracy than rigid methods. However, due to the irregularities in some of the obtained deformation fields, warping the SPECT using these fields may result in unacceptable changes to the SPECT intensity distribution that would preclude use in RT planning. Moreover, the differences between intensity histograms in the original and registered SPECT image sets were the largest for diffeomorphic demons and level set methods. In conclusion, the use of intensity-based validation measures alone is not sufficient for SPECT/CT registration for RTTP. It was also found that the proper evaluation of image registration requires the use of several accuracy metrics.

Development of a new statistical evaluation method for brain SPECT images

International Nuclear Information System (INIS)

Kawashima, Ryuta; Sato, Kazunori; Ito, Hiroshi; Koyama, Masamichi; Goto, Ryoui; Yoshioka, Seiro; Ono, Shuichi; Sato, Tachio; Fukuda, Hiroshi

1996-01-01

The purpose of this study was to develop a new statistical evaluation method for brain SPECT images. First, we made normal brain image databases using 99m Tc-ECD and SPECT in 10 normal subjects as described previously. Each SPECT images were globally normalized and anatomically standardized to the standard brain shape using Human Brain Atlas (HBA) of Roland et al. and each subject's X-CT. Then, mean and SD images were calculated voxel by voxel. For the next step, 99m Tc-ECD SPECT images of a patient were obtained, and global normalization and anatomical standardization were performed as the same way. Then, a statistical map was calculated as following voxel by voxel; (P-Mean)/SDx10+50, where P, mean and SD indicate voxel value of patient, mean and SD images of normal databases, respectively. We found this statistical map was helpful for clinical diagnosis of brain SPECT studies. (author)

Pre-evaluation study in SPECT images using a phantom

International Nuclear Information System (INIS)

Rebelo, Marina de Sa; Furuie, Sergio Shiguemi; Abe, Rubens; Moura, Lincoln

1996-01-01

An alternative solution for the reconstruction of SPECT images using a Poisson Noise Model is presented. The proposed algorithm was applied on a real phantom and compared to the standard clinical procedures. Results have shown that the proposed method improves the quality of the SPECT images

Quantitative Nuclear Medicine. Chapter 17

Energy Technology Data Exchange (ETDEWEB)

Ouyang, J.; El Fakhri, G. [Massachusetts General Hospital and Harvard Medical School, Boston (United States)

2014-12-15

Planar imaging is still used in clinical practice although tomographic imaging (single photon emission computed tomography (SPECT) and positron emission tomography (PET)) is becoming more established. In this chapter, quantitative methods for both imaging techniques are presented. Planar imaging is limited to single photon. For both SPECT and PET, the focus is on the quantitative methods that can be applied to reconstructed images.

SPECT versus planar bone radionuclide imaging in the detection of spondylolysis

International Nuclear Information System (INIS)

Whitten, C.G.; El-Khoury, G.Y.; Chang, P.J.; Seabold, J.E.; Found, E.M.; Renfrew, D.L.

1991-01-01

This paper evaluates the relative performance and ease of interpretation of SPECT versus planar radionuclide bone imaging in the detection of spondylolysis. The authors studied all patients presenting with back pain suggestive of spondylolysis from November 1989 to January 1991 who underwent bone scanning; patients underwent both planar and SPECT imaging. The planar and SPECT images were randomly mixed and independently interpreted by four observers for presence or absence of spondylolysis and ease of interpretation for each scan. Receiver operating characteristic (ROC) and analysis of variance (ANOVA) were used. Of 72 patients, 19 had confirmed spondylolysis, and 53 did not. While ROC analysis showed that SPECT performed slightly better than planar imaging for all four observers, the difference was not statistically significant. ANOVA results suggest that planar imaging was significantly easier to use than SPECT and that ease of use was strongly correlated with the observer's confidence in the diagnosis

Quantification in single photon emission computed tomography (SPECT)

International Nuclear Information System (INIS)

Buvat, Irene

2005-01-01

The objective of this lecture is to understand the possibilities and limitations of the quantitative analysis of single photon emission computed tomography (SPECT) images. It is also to identify the conditions to be fulfilled to obtain reliable quantitative measurements from images. Content: 1 - Introduction: Quantification in emission tomography - definition and challenges; quantification biasing phenomena; 2 - quantification in SPECT, problems and correction methods: Attenuation, scattering, un-stationary spatial resolution, partial volume effect, movement, tomographic reconstruction, calibration; 3 - Synthesis: actual quantification accuracy; 4 - Beyond the activity concentration measurement

Automated Analysis of 123I-beta-CIT SPECT Images with Statistical Probabilistic Anatomical Mapping

International Nuclear Information System (INIS)

Eo, Jae Seon; Lee, Hoyoung; Lee, Jae Sung; Kim, Yu Kyung; Jeon, Bumseok; Lee, Dong Soo

2014-01-01

Population-based statistical probabilistic anatomical maps have been used to generate probabilistic volumes of interest for analyzing perfusion and metabolic brain imaging. We investigated the feasibility of automated analysis for dopamine transporter images using this technique and evaluated striatal binding potentials in Parkinson's disease and Wilson's disease. We analyzed 2β-Carbomethoxy-3β-(4- 123 I-iodophenyl)tropane ( 123 I-beta-CIT) SPECT images acquired from 26 people with Parkinson's disease (M:F=11:15,mean age=49±12 years), 9 people with Wilson's disease (M: F=6:3, mean age=26±11 years) and 17 normal controls (M:F=5:12, mean age=39±16 years). A SPECT template was created using striatal statistical probabilistic map images. All images were spatially normalized onto the template, and probability-weighted regional counts in striatal structures were estimated. The binding potential was calculated using the ratio of specific and nonspecific binding activities at equilibrium. Voxel-based comparisons between groups were also performed using statistical parametric mapping. Qualitative assessment showed that spatial normalizations of the SPECT images were successful for all images. The striatal binding potentials of participants with Parkinson's disease and Wilson's disease were significantly lower than those of normal controls. Statistical parametric mapping analysis found statistically significant differences only in striatal regions in both disease groups compared to controls. We successfully evaluated the regional 123 I-beta-CIT distribution using the SPECT template and probabilistic map data automatically. This procedure allows an objective and quantitative comparison of the binding potential, which in this case showed a significantly decreased binding potential in the striata of patients with Parkinson's disease or Wilson's disease

Assessment of vascularization within hydroxyapatite ocular implant by bone scintigraphy: compartive analysis of planar and SPECT imaging

International Nuclear Information System (INIS)

Lim, Seok Tae; Sohn, Myung Hee; Park, Soon Ah

1999-01-01

Complete fibrovascular ingrowth within the hydroxyapatite ocular implant is necessary for peg drilling which is performed to prevent infection and to provide motility to the ocular prosthesis. We compared planar bone scintigraphy and SPECT for the evaluation of the vascularization within hydroxyapatite ocular implants. Seventeen patients (M:F=12:5, mean age: 50.4±17.5 years) who had received a coralline hydroxyapatite ocular implant after enucleation surgery were enrolled. Patients underwent Tc-99m MDP planar bone and SPECT imaging by dual head gamma camera after their implant surgery (interval: 197±81 days). Uptake on planar and SPECT images was graded visually as less than (grade 1), equal to (grade 2), and greater than (grade 3) nasal bridge activity. Quantitative ratio of implanted to non-implanted intraorbital activity was also measured. Vascularization within hydroxyapatite implants was confirmed by slit lamp examination and ocular movement. All but three patients were considered to be vascularized within hydroxyapatite implants. In visual analysis of planar image and SPECT, grade 1 was noted in 9/18 (50%) and 6/18 (33%), respectively. Grade 2 pattern 7/18 (39%) and 4/18 (22%), and grade 3 pattern was 2/18 (11%) and 8/18 (44%) respectively. When grade 2 or 3 was considered to be positive for vascularization, the sensitivity of planar and SPECT imaging were 60% (9/15) and 80% (12/15), respectively. In 3 patients with incomplete vascularization, both planar and SPECT showed grade 1 uptake. The orbital activity ratios on planar imaging were not significantly different between complete and incomplete vascularization (1.96±9.87 vs 1.17±0.08 , p>0.05), however, it was significantly higher on SPECT in patients with complete vascularization (8.44±5.45 vs 2.20±0.87, p<0.05). In the assessment of fibrovascular ingrowth within ocular implants by Tc-99m MDP bone scintigraphy, SPECT image appears to be more effective than planar scintigraphy

Utility of Quantitative 99mTc-MAA SPECT/CT for 90yttrium-Labelled Microsphere Treatment Planning: Calculating Vascularized Hepatic Volume and Dosimetric Approach

Science.gov (United States)

Garin, Etienne; Rolland, Yan; Lenoir, Laurence; Pracht, Marc; Mesbah, Habiba; Porée, Philippe; Laffont, Sophie; Clement, Bruno; Raoul, Jean-Luc; Boucher, Eveline

2011-01-01

Objectives. The aim of this study was to assess the effectiveness of SPECT/CT for volume measurements and to report a case illustrating the major impact of SPECT/CT in calculating the vascularized liver volume and dosimetry prior to injecting radiolabelled yttrium-90 microspheres (Therasphere). Materials and Methods. This was a phantom study, involving volume measurements carried out by two operators using SPECT and SPECT/CT images. The percentage of error for each method was calculated, and interobserver reproducibility was evaluated. A treatment using Therasphere was planned in a patient with three hepatic arteries, and the quantitative analysis of SPECT/CT for this patient is provided. Results. SPECT/CT volume measurements proved to be accurate (mean error Therasphere used. Conclusions. MAA SPECT/CT is accurate for vascularized liver volume measurements, providing a valuable contribution to the therapeutic planning of patients with complex hepatic vascularization. PMID:21822489

Radiotracers for SPECT imaging. Current scenario and future prospects

International Nuclear Information System (INIS)

Adak, S.; Vijaya Raj, K.K.; Mandal, S.

2012-01-01

Single photon emission computed tomography (SPECT) has been the cornerstone of nuclear medicine and today it is widely used to detect molecular changes in cardiovascular, neurological and oncological diseases. While SPECT has been available since the 1980s, advances in instrumentation hardware, software and the availability of new radiotracers that are creating a revival in SPECT imaging are reviewed in this paper. The biggest change in the last decade has been the fusion of CT with SPECT, which has improved attenuation correction and image quality. Advances in collimator design, replacement of sodium iodide crystals in the detectors with cadmium zinc telluride (CZT) detectors as well as advances in software and reconstruction algorithms have all helped to retain SPECT as a much needed and used technology. Today, a wide spectrum of radiotracers is available for use in cardiovascular, neurology and oncology applications. The development of several radiotracers for neurological disorders is briefly described in this review, including [ 123 I]FP-CIT (DaTSCAN trademark) available for Parkinson's disease. In cardiology, while technetium-99m labeled tetrofosmin and technetium-99m labeled sestamibi have been well known for myocardial perfusion imaging, we describe a recently completed multicenter clinical study on the use of [ 123 I]mIBG (AdreView trademark) for imaging in chronic heart failure patients. For oncology, while bone scanning has been prevalent, newer radiotracers that target cancer mechanisms are being developed. Technetium-99m labeled RGD peptides have been reported in the literature that can be used for imaging angiogenesis, while technetium-99m labeled duramycin has been used to image apoptosis. While PET/CT is considered to be the more advanced technology particularly for oncology applications, SPECT continues to be the modality of choice and the workhorse in many hospitals and nuclear medicine centers. The cost of SPECT instruments also makes them more

Radiotracers for SPECT imaging. Current scenario and future prospects

Energy Technology Data Exchange (ETDEWEB)

Adak, S.; Vijaya Raj, K.K.; Mandal, S. [GE Healthcare Medical Diagnostics, John F. Welch Technology Center, Bangalore (India).; Bhalla, R.; Pickett, R.; Luthra, S.K. [GE Healthcare Medical Diagnostics, The Grove Centre, Amersham (United Kingdom)

2012-07-01

Single photon emission computed tomography (SPECT) has been the cornerstone of nuclear medicine and today it is widely used to detect molecular changes in cardiovascular, neurological and oncological diseases. While SPECT has been available since the 1980s, advances in instrumentation hardware, software and the availability of new radiotracers that are creating a revival in SPECT imaging are reviewed in this paper. The biggest change in the last decade has been the fusion of CT with SPECT, which has improved attenuation correction and image quality. Advances in collimator design, replacement of sodium iodide crystals in the detectors with cadmium zinc telluride (CZT) detectors as well as advances in software and reconstruction algorithms have all helped to retain SPECT as a much needed and used technology. Today, a wide spectrum of radiotracers is available for use in cardiovascular, neurology and oncology applications. The development of several radiotracers for neurological disorders is briefly described in this review, including [{sup 123}I]FP-CIT (DaTSCAN trademark) available for Parkinson's disease. In cardiology, while technetium-99m labeled tetrofosmin and technetium-99m labeled sestamibi have been well known for myocardial perfusion imaging, we describe a recently completed multicenter clinical study on the use of [{sup 123}I]mIBG (AdreView trademark) for imaging in chronic heart failure patients. For oncology, while bone scanning has been prevalent, newer radiotracers that target cancer mechanisms are being developed. Technetium-99m labeled RGD peptides have been reported in the literature that can be used for imaging angiogenesis, while technetium-99m labeled duramycin has been used to image apoptosis. While PET/CT is considered to be the more advanced technology particularly for oncology applications, SPECT continues to be the modality of choice and the workhorse in many hospitals and nuclear medicine centers. The cost of SPECT instruments also

Atlas of Skeletal SPECT/CT Clinical Images

International Nuclear Information System (INIS)

2016-01-01

The atlas focuses specifically on single photon emission computed tomography/computed tomography (SPECT/CT) in musculoskeletal imaging, and thus illustrates the inherent advantages of the combination of the metabolic and anatomical component in a single procedure. In addition, the atlas provides information on the usefulness of several sets of specific indications. The publication, which serves more as a training tool rather than a textbook, will help to further integrate the SPECT and CT experience in clinical practice by presenting a series of typical cases with many different patterns of SPECT/CT seen in bone scintigraphy

Rapid gated Thallium-201 perfusion SPECT - clinically feasible?

International Nuclear Information System (INIS)

Wadhwa, S.S.; Mansberg, R.; Fernandes, V.B.; Wilkinson, D.; Abatti, D.

1998-01-01

Full text: Standard dose energy window optimised Thallium-201 (Tl-201) SPECT has about half the counts of a standard dose from Technetium-99m Sestamibi (Tc99m-Mibi) gated perfusion SPECT. This study investigates the clinical feasibility of rapid energy window optimised Tl-201 gated perfusion SPECT (gated-TI) and compares quantitative left ventricular ejection fraction (LVEF) and visually assessed image quality for wall motion and thickening to analogous values obtained from Tc99m-Mibi gated perfusion SPECT (gated - mibi). Methods: We studied 60 patients with a rest gated Tl-201 SPECT (100 MBq, 77KeV peak, 34% window, 20 sec/projection) followed by a post stress gated Sestamibi SPECT (1GBq, 140KeV, 20% window, 20 sec/projection) separate dual isotope protocol. LVEF quantitation was performed using commercially available software (SPECTEF, General Electric). Visual grading of image quality for wall thickening and motion was performed using a three-point scale (excellent, good and poor). Results: LVEF for gated Tl-201 SPECT was 59.6 ± 12.0% (Mean ± SD). LVEF for gated Sestamibi SPECT was 60.4 ±11.4% (Mean ± SD). These were not significantly different (P=0.27, T-Test). There was good correlation (r=0.9) between gated-TI and gated-mibi LVEF values. The quality of gated-Tl images was ranked as excellent, good and poor in 12, 50 and 38% of the patients respectively. Image quality was better in gated-mibi SPECT, with ratings of 12, 62 and 26% respectively. Conclusion: Rapid gated Thallium-201 acquisition with energy window optimisation can be effectively performed on majority of patients and offers the opportunity to assess not only myocardial perfusion and function, as with Technetium based agents, but also viability using a single day one isotope protocol

Onboard functional and molecular imaging: A design investigation for robotic multipinhole SPECT

International Nuclear Information System (INIS)

Bowsher, James; Giles, William; Yin, Fang-Fang; Yan, Susu; Roper, Justin

2014-01-01

Purpose: Onboard imaging—currently performed primarily by x-ray transmission modalities—is essential in modern radiation therapy. As radiation therapy moves toward personalized medicine, molecular imaging, which views individual gene expression, may also be important onboard. Nuclear medicine methods, such as single photon emission computed tomography (SPECT), are premier modalities for molecular imaging. The purpose of this study is to investigate a robotic multipinhole approach to onboard SPECT. Methods: Computer-aided design (CAD) studies were performed to assess the feasibility of maneuvering a robotic SPECT system about a patient in position for radiation therapy. In order to obtain fast, high-quality SPECT images, a 49-pinhole SPECT camera was designed which provides high sensitivity to photons emitted from an imaging region of interest. This multipinhole system was investigated by computer-simulation studies. Seventeen hot spots 10 and 7 mm in diameter were placed in the breast region of a supine female phantom. Hot spot activity concentration was six times that of background. For the 49-pinhole camera and a reference, more conventional, broad field-of-view (FOV) SPECT system, projection data were computer simulated for 4-min scans and SPECT images were reconstructed. Hot-spot localization was evaluated using a nonprewhitening forced-choice numerical observer. Results: The CAD simulation studies found that robots could maneuver SPECT cameras about patients in position for radiation therapy. In the imaging studies, most hot spots were apparent in the 49-pinhole images. Average localization errors for 10-mm- and 7-mm-diameter hot spots were 0.4 and 1.7 mm, respectively, for the 49-pinhole system, and 3.1 and 5.7 mm, respectively, for the reference broad-FOV system. Conclusions: A robot could maneuver a multipinhole SPECT system about a patient in position for radiation therapy. The system could provide onboard functional and molecular imaging with 4-min

Onboard functional and molecular imaging: A design investigation for robotic multipinhole SPECT

Energy Technology Data Exchange (ETDEWEB)

Bowsher, James, E-mail: james.bowsher@duke.edu; Giles, William; Yin, Fang-Fang [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 and Medical Physics Graduate Program, Duke University, Durham, North Carolina 27710 (United States); Yan, Susu [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27710 (United States); Roper, Justin [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 (United States)

2014-01-15

Purpose: Onboard imaging—currently performed primarily by x-ray transmission modalities—is essential in modern radiation therapy. As radiation therapy moves toward personalized medicine, molecular imaging, which views individual gene expression, may also be important onboard. Nuclear medicine methods, such as single photon emission computed tomography (SPECT), are premier modalities for molecular imaging. The purpose of this study is to investigate a robotic multipinhole approach to onboard SPECT. Methods: Computer-aided design (CAD) studies were performed to assess the feasibility of maneuvering a robotic SPECT system about a patient in position for radiation therapy. In order to obtain fast, high-quality SPECT images, a 49-pinhole SPECT camera was designed which provides high sensitivity to photons emitted from an imaging region of interest. This multipinhole system was investigated by computer-simulation studies. Seventeen hot spots 10 and 7 mm in diameter were placed in the breast region of a supine female phantom. Hot spot activity concentration was six times that of background. For the 49-pinhole camera and a reference, more conventional, broad field-of-view (FOV) SPECT system, projection data were computer simulated for 4-min scans and SPECT images were reconstructed. Hot-spot localization was evaluated using a nonprewhitening forced-choice numerical observer. Results: The CAD simulation studies found that robots could maneuver SPECT cameras about patients in position for radiation therapy. In the imaging studies, most hot spots were apparent in the 49-pinhole images. Average localization errors for 10-mm- and 7-mm-diameter hot spots were 0.4 and 1.7 mm, respectively, for the 49-pinhole system, and 3.1 and 5.7 mm, respectively, for the reference broad-FOV system. Conclusions: A robot could maneuver a multipinhole SPECT system about a patient in position for radiation therapy. The system could provide onboard functional and molecular imaging with 4-min

High resolution SPECT imaging for visualization of intratumoral heterogeneity using a SPECT/CT scanner dedicated for small animal imaging

International Nuclear Information System (INIS)

Umeda, Izumi O.; Tani, Kotaro; Tsuda, Keisuke

2012-01-01

Tumor interiors are never homogeneous and in vivo visualization of intratumoral heterogeneity would be an innovation that contributes to improved cancer therapy. But, conventional nuclear medicine tests have failed to visualize heterogeneity in vivo because of limited spatial resolution. Recently developed single photon emission computed tomographic (SPECT) scanners dedicated for small animal imaging are of interest due to their excellent spatial resolution of 111 In and simulations of actual small animal imaging. The optimal conditions obtained were validated by in vivo imaging of sarcoma 180-bearing mice. Larger number of counts must be obtained within limited acquisition time to visualize tumor heterogeneity in vivo in animal imaging, compared to cases that simply detect tumors. At an acquisition time of 30 min, better image quality was obtained with pinhole apertures diameter of 1.4 mm than of 1.0 mm. The obtained best spatial resolution was 1.3 mm, it was acceptable for our purpose, though a little worse than the best possible performance of the scanner (1.0 mm). Additionally, the reconstruction parameters, such as noise suppression, voxel size, and iteration/subset number, needed to be optimized under the limited conditions and were different from those found under the ideal condition. The minimal radioactivity concentration for visualization of heterogeneous tumor interiors was estimated to be as high as 0.2-0.5 MBq/mL. Liposomes containing 111 In met this requirement and were administered to tumor-bearing mice. SPECT imaging successfully showed heterogeneous 111 In distribution within the tumors in vivo with good spatial resolution. A threshold of 0.2 MBq/g for clear visualization of tumor heterogeneity was validated. Autoradiograms obtained ex vivo of excised tumors confirmed that the in vivo SPECT images accurately depicted the heterogeneous intratumoral accumulation of liposomes. Intratumoral heterogeneity was successfully visualized under the optimized

Usefulness of Ga-67 citrate whole body imaging, chest spot imaging, and chest SPECT in sarcoidosis

International Nuclear Information System (INIS)

Ueno, Kyoichi; Nishi, Koichi; Namura, Masanobu; Kawashima, Yoshio; Kurumaya, Hiroshi

1999-01-01

To assess the sensitivity, and the relative role of Ga-67 whole body, chest spot imaging, and chest SPECT, we retrospectively studied 34 cases of sarcoidosis (24 biopsy proven, 10 clinically diagnosed) with Ga-67 (111 MBq), and compared the results of lung (25 cases), muscle (25 cases), skin (3 cases), and myocardial (2 cases) biopsies. Ga-67 chest SPECT (single photon emission CT) were done in 17 cases with Siemens MultiSPECT3. Ga-67 planar imaging visualized only 2 of 12 (16.7%) lung biopsy-positive cases, 5 of 12 (41.6%) muscle biopsy-positive cases, 2 of 3 (66.7%) skin biopsy-positive cases. However, Ga-67 imaging revealed the lesions in 1 of 9 (11.1%) of muscle biopsy-negative cases, in 2 of 3 (66.7%) of skin biopsy-negative cases, and in 1 of 2 myocardial biopsy-negative cases. Ga-67 chest SPECT visualized 14 hilar lymphadenopathy (LN), 3 supraclavicular LN, and 1 myocardial sarcoidosis. Although both SPECT, and planar spot imaging detected the lesions equally, the former showed them more clearly. Compared with various biopsies, the sensitivity of Ga-67 imaging was not so high. However, Ga-67 imaging is non-invasive, easy to perform the whole body imaging, and can detect the activity of the lesions. Ga-67 SPECT showed clear imaging of the hilar, mediastinal LN, and potentially fatal myocardial sarcoidosis. (author)

Significance of 99mTc-MIBI myocardial SPECT imaging in diagnosis of syndrome X

International Nuclear Information System (INIS)

Tian Yueqing; Liu Xiujie; Jiao Shubin

1996-01-01

To assess the value of myocardial imaging in the diagnosis of syndrome X, the study was performed with 99m Tc-MIBI myocardial SPECT imaging in 64 patients. The patients were divided into three groups: group 1 had 21 patients diagnosed as syndrome X, group 2 had 17 patients with chest pain and normal coronary arteries without ST segment depression during exercise, group 3 had 26 patients with the angina pectoris and coronary stenoses≥50%. The myocardial SPECT imaging of the three groups was compared qualitatively and semi-quantitatively. Myocardial imaging identified 11 cases of myocardial ischemia from 21 patients with syndrome X. The ischemic score of myocardial imaging was 1.1 +- 0.3 for syndrome X and 1.8 +- 0.7 for patients with coronary heart disease (CHD) angina pectoris (t = 3.1746, P<0.01). Myocardial imaging may partly show myocardial ischemia in patients with syndrome X. The extent of ischemia in patients with syndrome X was significantly less than that in patients with CHD angina pectoris

Optimisation of quantitative lung SPECT applied to mild COPD: a software phantom simulation study.

Science.gov (United States)

Norberg, Pernilla; Olsson, Anna; Alm Carlsson, Gudrun; Sandborg, Michael; Gustafsson, Agnetha

2015-01-01

The amount of inhomogeneities in a (99m)Tc Technegas single-photon emission computed tomography (SPECT) lung image, caused by reduced ventilation in lung regions affected by chronic obstructive pulmonary disease (COPD), is correlated to disease advancement. A quantitative analysis method, the CVT method, measuring these inhomogeneities was proposed in earlier work. To detect mild COPD, which is a difficult task, optimised parameter values are needed. In this work, the CVT method was optimised with respect to the parameter values of acquisition, reconstruction and analysis. The ordered subset expectation maximisation (OSEM) algorithm was used for reconstructing the lung SPECT images. As a first step towards clinical application of the CVT method in detecting mild COPD, this study was based on simulated SPECT images of an advanced anthropomorphic lung software phantom including respiratory and cardiac motion, where the mild COPD lung had an overall ventilation reduction of 5%. The best separation between healthy and mild COPD lung images as determined using the CVT measure of ventilation inhomogeneity and 125 MBq (99m)Tc was obtained using a low-energy high-resolution collimator (LEHR) and a power 6 Butterworth post-filter with a cutoff frequency of 0.6 to 0.7 cm(-1). Sixty-four reconstruction updates and a small kernel size should be used when the whole lung is analysed, and for the reduced lung a greater number of updates and a larger kernel size are needed. A LEHR collimator and 125 (99m)Tc MBq together with an optimal combination of cutoff frequency, number of updates and kernel size, gave the best result. Suboptimal selections of either cutoff frequency, number of updates and kernel size will reduce the imaging system's ability to detect mild COPD in the lung phantom.

Technical Considerations of Phosphorous-32 Bremsstrahlung SPECT Imaging after Radio embolization of Hepatic Tumors: A Clinical Assessment with a Review of Imaging Parameters

International Nuclear Information System (INIS)

Pirayesh, E.; Amoui, M.; Khorrami, M.; Akhlaghpoor, Sh.; Tolooee, Sh.; PoorBeigi, H.; Sheibani, Sh.; Assadi, M.

2014-01-01

Bremsstrahlung (BS) imaging during radio embolization (RE) confirms the deposition of radiotracer in hepatic/extrahepatic tumors. The aim of this study is to demonstrate '3 2 P images and to optimize the imaging parameters. Materials and Methods. Thirty-nine patients with variable types of hepatic tumors, treated with the intra-arterial injection of 32 P, were included. All patients underwent BS SPECT imaging 24-72 h after tracer administration, using low energy high resolution (LEHR) (18 patients) or medium energy general purpose (MEGP) (21 patients) collimators. A grading scale from 1 to 4 was used to express the compatibility of the 32 P images with those obtained from CT/MRI. Results. Although the image quality obtained with the MEGP collimator was visually and quantitatively better than with the LEHR (76% concordance score versus 71%, resp.), there was no statistically significant difference between them. Conclusion. The MEGP collimator is the first choice for BS SPECT imaging. However, if the collimator change is time consuming (as in a busy center) or an MEGP collimator is not available, the LEHR collimator could be practical with acceptable images, especially in a SPECT study. In addition, BS imaging is a useful method to confirm the proper distribution of radiotherapeutic agents and has good correlation with anatomical findings.

Quantitative evaluation of regional cerebral blood flow by visual stimulation in 99mTc-HMPAO brain SPECT

International Nuclear Information System (INIS)

Juh, R. H.; Suh, T. S.; Chung, Y. A.

2002-01-01

The purpose of this study is to investigate the effects of visual activation and quantitative analysis of regional cerebral blood flow. Visual activation was known to increase regional cerebral blood flow in the visual cortex in occipital lobe. We evaluated that change in the distribution of 99mTc-HMPAO (Hexamethyl propylene amine oxime) to reflect in regional cerebral blood flow. The six volunteers were injected with 925 MBq (mean ages: 26.75 years, n=6, 3men, 3women) underwent MRI and 99mTc- HMPAO SPECT during a rest state with closed eyes and visual stimulated with 8 Hz LED. We delineate the region of interest and calculated the mean count per voxel in each of the fifteen slices to quantitative analysis. The ROI to whole brain ratio and regional index was calculated pixel to pixel subtraction visual non-activation image from visual activation image and constructed brain map using a statistical parameter map (SPM99). The mean regional cerebral blood flow was increased due to visual stimulation. The increase rate of the mean regional cerebral blood flow which of the activation region in primary visual cortex of occipital lobe was 32.50±5.67%. The significant activation sites using a statistical parameter of brain constructed a rendering image and image fusion with SPECT and MRI. Visual activation was revealed significant increase through quantitative analysis in visual cortex. Activation region was certified in Talairach coordinate and primary visual cortex (Ba17),visual association area (Ba18,19) of Brodmann

Quantitative evaluation of regional cerebral blood flow by visual stimulation in 99mTc- HMPAO brain SPECT

International Nuclear Information System (INIS)

Juh, Ra Hyeong; Suh, Tae Suk; Kwark, Chul Eun; Choe, Bo Young; Lee, Hyoung Koo; Chung, Yong An; Kim, Sung Hoon; Chung, Soo Kyo

2002-01-01

The purpose of this study is to investigate the effects of visual activation and quantitative analysis of regional cerebral blood flow. Visual activation was known to increase regional cerebral blood flow in the visual cortex in occipital lobe. We evaluated that change in the distribution of '9 9m Tc-HMPAO (Hexamethyl propylene amine oxime) to reflect in regional cerebral blood flow. The six volunteers were injected with 925 MBq (mean ages: 26.75 years, n=6, 3men, 3women) underwent MRI and 99m Tc-HMPAO SPECT during a rest state with closed eyes and visual stimulated with 8 Hz LED. We delineate the region of interest and calculated the mean count per voxel in each of the fifteen slices to quantitative analysis. The ROI to whole brain ratio and regional index was calculated pixel to pixel subtraction visual non-activation image from visual activation image and constructed brain map using a statistical parameter map(SPM99). The mean regional cerebral blood flow was increased due to visual stimulation. The increase rate of the mean regional cerebral blood flow which of the activation region in primary visual cortex of occipital lobe was 32.50±5.67%. The significant activation sites using a statistical parameter of brain constructed a rendering image and image fusion with SPECT and MRI. Visual activation was revealed significant increase through quantitative analysis in visual cortex. Activation region was certified in Talairach coordinate and primary visual cortex (Ba17),visual association area (Ba18,19) of Brodmann

Is SPECT useful in imaging of abdominal inflammatory processes using 99mTc-HMPAO-WBCs?

International Nuclear Information System (INIS)

Smole, M.S.; Stantic, T.S.; Fettich, J.F.

2002-01-01

Aim: The aim of the study is to determine whether SPECT gives additional information in the assessment of inflammation of the abdominal region with labelled white blood cells as compared with usual planar imaging. Patients And Methods: SPECT and planar imaging was performed in 26 patients with suspected inflammatory process in the abdomen, within three hours after injection of autologous white blood cells labelled with 99m Tc HMPAO. Planar images where acquired as static spot images using high resolution low energy collimator on 256 x 256 matrix. SPECT was performed using the same collimator on 128 x 128 matrix in 128 projections. Filtered back projection was used for reconstruction and volume rendering was performed. Results: The lesions in the abdomen were classified as jejunum, colon ascendents, colon transversum, colon descendents, sigmoid, and lesions outside GIT. All lesions, which were seen on planar images, except one, were also seen on SPECT. Five equivocal lesions seen on planar images were reconfirmed as pathological on SPECT. Additionally SPECT revealed three lesions not seen on planar images. Fourteen lesions were seen by both imaging techniques. All together SPECT improved diagnostic accuracy of 99m Tc - HMPAO - WBC scintigraphy in 7/28 patients. Conclusion: more inflammatory lesions in the abdomen are revealed by SPECT and volume rendering, than by planar imaging equivocal lesions seen on planar images can be characterised as positive or negative by SPECT. SPECT artefacts can cause possible false positive results; therefore usual planar imaging cannot be omitted if SPECT is performed

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

Diagnosis and staging of breast cancer by SPECT images fused with CT images

International Nuclear Information System (INIS)

Li Yanjing; Zhu Qiaomei

2007-01-01

Objective: To evaluate the TNM staging value of 99mTc-MIBI scintimammotraphy with SPECT-CT images fusing for the diagnosis of breast cancer. Methods: 10 patients with breast cancer underwent scintimammography with 99mTc-MIBI, and SPECT images were fused with CT images. Images were compared with final diagnosis confirmed by histopathology. Results: Of the 19 breast cancer patients, one case of invasive ductal carcinoma showed false-negative. Among 18 cases of positive lesions, axillary metastases were involved in 10, supraclavicular nodes were also defined in 3, para-sternum nodes were involved in 2, 2 were missed and 1 cases without metastatic node. The axillary lymph nodes were divided into three levels with respect to their position relative to the pectoralis minor muscle by fused images. Conclusion: 99mTc-MIBI scintimammotraphy combined with SPECT-CT images fusing is of some clinical value in TNM staging of breast cancer. (authors)

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

International Nuclear Information System (INIS)

Bernal, P.; Ucros, G.; Bermudez, S.; Ocampo, M.

2007-01-01

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

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)

[Development of a Striatal and Skull Phantom for Quantitative 123I-FP-CIT SPECT].

Science.gov (United States)

Ishiguro, Masanobu; Uno, Masaki; Miyazaki, Takuma; Kataoka, Yumi; Toyama, Hiroshi; Ichihara, Takashi

123 Iodine-labelled N-(3-fluoropropyl) -2β-carbomethoxy-3β-(4-iodophenyl) nortropane ( 123 I-FP-CIT) single photon emission computerized tomography (SPECT) images are used for differential diagnosis such as Parkinson's disease (PD). Specific binding ratio (SBR) is affected by scattering and attenuation in SPECT imaging, because gender and age lead to changes in skull density. It is necessary to clarify and correct the influence of the phantom simulating the the skull. The purpose of this study was to develop phantoms that can evaluate scattering and attenuation correction. Skull phantoms were prepared based on the measuring the results of the average computed tomography (CT) value, average skull thickness of 12 males and 16 females. 123 I-FP-CIT SPECT imaging of striatal phantom was performed with these skull phantoms, which reproduced normal and PD. SPECT images, were reconstructed with scattering and attenuation correction. SBR with partial volume effect corrected (SBR act ) and conventional SBR (SBR Bolt ) were measured and compared. The striatum and the skull phantoms along with 123 I-FP-CIT were able to reproduce the normal accumulation and disease state of PD and further those reproduced the influence of skull density on SPECT imaging. The error rate with the true SBR, SBR act was much smaller than SBR Bolt . The effect on SBR could be corrected by scattering and attenuation correction even if the skull density changes with 123 I-FP-CIT on SPECT imaging. The combination of triple energy window method and CT-attenuation correction method would be the best correction method for SBR act .

Comparison of SPECT and whole-body planar imaging in radioimmunoscintigraphy with Tc-labeled antibodies

International Nuclear Information System (INIS)

Lacic, K.; Bokulic, T.; Lukac, J.; Dakovic, N.; Kusic, Z.

1994-01-01

The authors of some recent clinical studies suggested 20-24 hours SPECT imaging as a mandatory procedure in radioimmunoscintigraphy with Tc-labeled antibodies. The aim of our study was to compare whole-body (WB) planar imaging versus SPECT as well as 4-6 hours SPECT to 20-24 hours one. For this purpose we analyzed 33 lesions in 12 postsurgical patients with colorectal carcinoma. Each patient received intravenously 0.5-1.0 mg anti-CEA BW 431/26 murine monoclonal IgG-antibodies labeled with Tc-99m (814-1110 MBq). WB and SPECT imaging were performed at 4-6 and 20-24 hours post infusion. 20-24 hours WB scan imaged more 'hot' and less 'cold' lesions than 4-6 hours one. SPECT scan showed significantly more lesions than WB scan. 20-24 hours SPECT scan detected more 'hot' lesions than 4-6 hours SPECT. At the same time the number of 'cold' lesions decreased in 20-24 hours SPECT in comparison to 4-6 hours one. As a conclusion we can say that our results suggest a superiority of SPECT imaging in comparison to WB scan. Except that, in our opinion performing of a 20-24 hours SPECT scan in radioimmunoscintigraphy with Tc-labeled antibodies should be mandatory. (author)

Comparison of SPECT and whole-body planar imaging in radioimmunoscintigraphy with Tc-labeled antibodies

Energy Technology Data Exchange (ETDEWEB)

Lacic, K; Bokulic, T; Lukac, J; Dakovic, N; Kusic, Z [Clinical Hospital Sestre Milosrdnice, Zagreb (Croatia). Dept. of Oncology and Nuclear Medicine

1994-10-01

The authors of some recent clinical studies suggested 20-24 hours SPECT imaging as a mandatory procedure in radioimmunoscintigraphy with Tc-labeled antibodies. The aim of our study was to compare whole-body (WB) planar imaging versus SPECT as well as 4-6 hours SPECT to 20-24 hours one. For this purpose we analyzed 33 lesions in 12 postsurgical patients with colorectal carcinoma. Each patient received intravenously 0.5-1.0 mg anti-CEA BW 431/26 murine monoclonal IgG-antibodies labeled with Tc-99m (814-1110 MBq). WB and SPECT imaging were performed at 4-6 and 20-24 hours post infusion. 20-24 hours WB scan imaged more `hot` and less `cold` lesions than 4-6 hours one. SPECT scan showed significantly more lesions than WB scan. 20-24 hours SPECT scan detected more `hot` lesions than 4-6 hours SPECT. At the same time the number of `cold` lesions decreased in 20-24 hours SPECT in comparison to 4-6 hours one. As a conclusion we can say that our results suggest a superiority of SPECT imaging in comparison to WB scan. Except that, in our opinion performing of a 20-24 hours SPECT scan in radioimmunoscintigraphy with Tc-labeled antibodies should be mandatory. (author).

Image viewing station for MR and SPECT : using personal computer

International Nuclear Information System (INIS)

Yim, Byung Il; Jeong, Eun Kee; Suh, Jin Suck; Kim, Myeong Joon

1996-01-01

Macro language was programmed to analyze and process on Macintosh personal computers, GEMR images digitally transferred from the MR main computer, with special interest in the interpretation of information such as patients data and imaging parameters under each image header. By this method, raw data(files) of certain patients may be digitally stored on a hard disk or CD ROM, and the quantitative analysis, interpretation and display is possible. Patients and images were randomly selected 4.X MR images were transferred through FTP using the ethernet network. 5.X and SPECT images were transferred using floppy diskettes. To process transferred images, an freely distributed software for Macintosh namely NIH Image, with its macro language, was used to import images and translate header information. To identify necessary information, a separate window named I nfo=txt , was made for each image series. MacLC, Centris650, and PowerMac6100/CD, 7100/CD, 8100/CD models with 256 color and RAM over 8Mbyte were used. Different versions of MR images and SPECT images were displayed simultaneously and a separate window named 'info-txt' was used to show all necessary information(name of the patient, unit number, date, TR, TE, FOV etc.). Additional information(diagnosis, pathologic report etc.) was stored in another text box in 'info-txt'. The size of the file for each image plane was about 149Kbytes and the images were stored in a step-like file folders. 4.X and 5.X GE Signa 1.5T images were successfully processed with Macintosh computer and NIH Image. This result may be applied to many fields and there is hope of a broader area of application with the linkage of NIH Image and a database program

Pulmonary function-morphologic relationships assessed by SPECT-CT fusion images

International Nuclear Information System (INIS)

Suga, Kazuyoshi

2012-01-01

Pulmonary single photon emission computed tomography-computed tomography (SPECT-CT) fusion images provide objective and comprehensive assessment of pulmonary function and morphology relationships at cross-sectional lungs. This article reviewed the noteworthy findings of lung pathophysiology in wide-spectral lung disorders, which have been revealed on SPECT-CT fusion images in 8 years of experience. The fusion images confirmed the fundamental pathophysiologic appearance of lung low CT attenuation caused by airway obstruction-induced hypoxic vasoconstriction and that caused by direct pulmonary arterial obstruction as in acute pulmonary thromboembolism (PTE). The fusion images showed better correlation of lung perfusion distribution with lung CT attenuation changes at lung mosaic CT attenuation (MCA) compared with regional ventilation in the wide-spectral lung disorders, indicating that lung heterogeneous perfusion distribution may be a dominant mechanism of MCA on CT. SPECT-CT angiography fusion images revealed occasional dissociation between lung perfusion defects and intravascular clots in acute PTE, indicating the importance of assessment of actual effect of intravascular colts on peripheral lung perfusion. Perfusion SPECT-CT fusion images revealed the characteristic and preferential location of pulmonary infarction in acute PTE. The fusion images showed occasional unexpected perfusion defects in normal lung areas on CT in chronic obstructive pulmonary diseases and interstitial lung diseases, indicating the ability of perfusion SPECT superior to CT for detection of mild lesions in these disorders. The fusion images showed frequent ''steal phenomenon''-induced perfusion defects extending to the surrounding normal lung of arteriovenous fistulas and those at normal lungs on CT in hepatopulmonary syndrome. Comprehensive assessment of lung function-CT morphology on fusion images will lead to more profound understanding of lung pathophysiology in wide-spectral lung

An automatic MRI/SPECT registration algorithm using image intensity and anatomical feature as matching characters: application on the evaluation of Parkinson's disease

International Nuclear Information System (INIS)

Lee, J.-D.; Huang, C.-H.; Weng, Y.-H.; Lin, K.-J.; Chen, C.-T.

2007-01-01

Single-photon emission computed tomography (SPECT) of dopamine transporters with 99m Tc-TRODAT-1 has recently been proposed to offer valuable information in assessing the functionality of dopaminergic systems. Magnetic resonance imaging (MRI) and SPECT imaging are important in the noninvasive examination of dopamine concentration in vivo. Therefore, this investigation presents an automated MRI/SPECT image registration algorithm based on a new similarity metric. This similarity metric combines anatomical features that are characterized by specific binding, the mean count per voxel in putamens and caudate nuclei, and the distribution of image intensity that is characterized by normalized mutual information (NMI). A preprocess, a novel two-cluster SPECT normalization algorithm, is also presented for MRI/SPECT registration. Clinical MRI/SPECT data from 18 healthy subjects and 13 Parkinson's disease (PD) patients are involved to validate the performance of the proposed algorithms. An appropriate color map, such as 'rainbow,' for image display enables the two-cluster SPECT normalization algorithm to provide clinically meaningful visual contrast. The proposed registration scheme reduces target registration error from >7 mm for conventional registration algorithm based on NMI to approximately 4 mm. The error in the specific/nonspecific 99m Tc-TRODAT-1 binding ratio, which is employed as a quantitative measure of TRODAT receptor binding, is also reduced from 0.45±0.22 to 0.08±0.06 among healthy subjects and from 0.28±0.18 to 0.12±0.09 among PD patients

Quantitatively accurate activity measurements with a dedicated cardiac SPECT camera: Physical phantom experiments

Energy Technology Data Exchange (ETDEWEB)

Pourmoghaddas, Amir, E-mail: apour@ottawaheart.ca; Wells, R. Glenn [Physics Department, Carleton University, Ottawa, Ontario K1S 5B6, Canada and Cardiology, The University of Ottawa Heart Institute, Ottawa, Ontario K1Y4W7 (Canada)

2016-01-15

Purpose: Recently, there has been increased interest in dedicated cardiac single photon emission computed tomography (SPECT) scanners with pinhole collimation and improved detector technology due to their improved count sensitivity and resolution over traditional parallel-hole cameras. With traditional cameras, energy-based approaches are often used in the clinic for scatter compensation because they are fast and easily implemented. Some of the cardiac cameras use cadmium-zinc-telluride (CZT) detectors which can complicate the use of energy-based scatter correction (SC) due to the low-energy tail—an increased number of unscattered photons detected with reduced energy. Modified energy-based scatter correction methods can be implemented, but their level of accuracy is unclear. In this study, the authors validated by physical phantom experiments the quantitative accuracy and reproducibility of easily implemented correction techniques applied to {sup 99m}Tc myocardial imaging with a CZT-detector-based gamma camera with multiple heads, each with a single-pinhole collimator. Methods: Activity in the cardiac compartment of an Anthropomorphic Torso phantom (Data Spectrum Corporation) was measured through 15 {sup 99m}Tc-SPECT acquisitions. The ratio of activity concentrations in organ compartments resembled a clinical {sup 99m}Tc-sestamibi scan and was kept consistent across all experiments (1.2:1 heart to liver and 1.5:1 heart to lung). Two background activity levels were considered: no activity (cold) and an activity concentration 1/10th of the heart (hot). A plastic “lesion” was placed inside of the septal wall of the myocardial insert to simulate the presence of a region without tracer uptake and contrast in this lesion was calculated for all images. The true net activity in each compartment was measured with a dose calibrator (CRC-25R, Capintec, Inc.). A 10 min SPECT image was acquired using a dedicated cardiac camera with CZT detectors (Discovery NM530c, GE

Pinhole SPECT: high resolution imaging of brain tumours in small laboratory animals

International Nuclear Information System (INIS)

Franceschim, M.; Bokulic, T.; Kusic, Z.; Strand, S.E.; Erlandsson, K.

1994-01-01

The performance properties of pinhole SPECT and the application of this technology to evaluate radionuclide uptake in brain in small laboratory animals were investigated. System sensitivity and spatial resolution measurements of a rotating scintillation camera system were made for a low energy pinhole collimator equipped with 2.0 mm aperture pinhole insert. Projection data were acquired at 4 degree increments over 360 degrees in the step and shoot mode using a 4.5 cm radius of rotation. Pinhole planar and SPECT imaging were obtained to evaluate regional uptake of Tl-201, Tc-99m-MIBI, Tc-99m-HMPAO and Tc-99m-DTPA in tumor and control regions of the brain in a primary brain tumor model in Fisher 344 rats. Pinhole SPECT images were reconstructed using a modified cone- beam algorithm developed from a two dimensional fan-beam filtered backprojection algorithm. The reconstructed transaxial resolution of 2.8 FWHM and system sensitivity of 0.086 c/s/kBq with the 2.0 mm pinhole collimator aperture were measured. Tumor to non-tumor uptake ratios at 19-28 days post tumor cell inoculation varied by a factor > 20:1 on SPECT images. Pinhole SPECT provides an important new approach for performing high resolution imaging: the resolution properties of pinhole SPECT are superior to those which have been achieved with conventional SPECT or PET imaging technologies. (author)

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

International Nuclear Information System (INIS)

Seiki, Yoshikatsu; Shibata, Iekado; Mito, Toshiaki; Sugo, Nobuo

2000-01-01

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

The current status of SPECT or SPECT/CT in South Korea

Energy Technology Data Exchange (ETDEWEB)

Yoo, Ik Dong; Choi, Eun Kyung; Chung, Yong An [Dept. of Radiology, Incheon Saint Mary' s HospitalThe Catholic University of Korea, Incheon (Korea, Republic of)

2017-06-15

The first step to nuclear medicine in Korea started with introduction of the gamma camera in 1969. Although planar images with the gamma camera give important functional information, they have the limitations that result from 2-dimensional images. Single-photon emission computed tomography (SPECT) due to its 3-dimensional image acquisition is superior to earlier planar gamma imaging in image resolution and diagnostic accuracy. As demand for a hybrid functional and anatomical imaging device has increased, integrated SPECT/CT systems have been used. In Korea, SPECT/CT was for the first time installed in 2003. SPECT/CT can eliminate many possible pitfalls on SPECT-alone images, making better attenuation correction and thereby improving image quality. Therefore, SPECT/CT is clinically preferred in many hospitals in various aspects. More recently, additional SPECT/CT images taken from the region with equivocal uptake on planar images have been helpful in making precise interpretation as part of their clinical workup in postoperative thyroid cancer patients. SPECT and SPECT/CT have various advantages, but its clinical application has gradually decreased in recent few years. While some researchers investigated the myocardial blood flow with cardiac PET using F-18 FDG or N-13 ammonia, myocardial perfusion SPECT is, at present, the radionuclide imaging study of choice for the risk stratification and guiding therapy in the coronary artery disease patients in Korea. New diagnostic radiopharmaceuticals for AD have received increasing attention; nevertheless, brain SPECT will remain the most reliable modality evaluating cerebral perfusion.

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)

Frameless image registration of X-ray CT and SPECT by volume matching

International Nuclear Information System (INIS)

Tanaka, Yuko; Kihara, Tomohiko; Yui, Nobuharu; Kinoshita, Fujimi; Kamimura, Yoshitsugu; Yamada, Yoshifumi.

1998-01-01

Image registration of functional (SPECT) and morphological (X-ray CT/MRI) images is studied in order to improve the accuracy and the quantity of the image diagnosis. We have developed a new frameless registration method of X-ray CT and SPECT image using transmission CT image acquired for absorption correction of SPECT images. This is the automated registration method and calculates the transformation matrix between the two coordinate systems of image data by the optimization method. This registration method is based on the similar physical property of X-ray CT and transmission CT image. The three-dimensional overlap of the bone region is used for image matching. We verified by a phantom test that it can provide a good result of within two millimeters error. We also evaluated visually the accuracy of the registration method by the application study of SPECT, X-ray CT, and transmission CT head images. This method can be carried out accurately without any frames. We expect this registration method becomes an efficient tool to improve image diagnosis and medical treatment. (author)

Quantitative evaluation of regional cerebral blood flow by visual stimulation in {sup 99m}Tc- HMPAO brain SPECT

Energy Technology Data Exchange (ETDEWEB)

Juh, Ra Hyeong; Suh, Tae Suk; Kwark, Chul Eun; Choe, Bo Young; Lee, Hyoung Koo; Chung, Yong An; Kim, Sung Hoon; Chung, Soo Kyo [College of Medicine, The Catholic Univ. of Seoul, Seoul (Korea, Republic of)

2002-06-01

The purpose of this study is to investigate the effects of visual activation and quantitative analysis of regional cerebral blood flow. Visual activation was known to increase regional cerebral blood flow in the visual cortex in occipital lobe. We evaluated that change in the distribution of '9{sup 9m}Tc-HMPAO (Hexamethyl propylene amine oxime) to reflect in regional cerebral blood flow. The six volunteers were injected with 925 MBq (mean ages: 26.75 years, n=6, 3men, 3women) underwent MRI and {sup 99m}Tc-HMPAO SPECT during a rest state with closed eyes and visual stimulated with 8 Hz LED. We delineate the region of interest and calculated the mean count per voxel in each of the fifteen slices to quantitative analysis. The ROI to whole brain ratio and regional index was calculated pixel to pixel subtraction visual non-activation image from visual activation image and constructed brain map using a statistical parameter map(SPM99). The mean regional cerebral blood flow was increased due to visual stimulation. The increase rate of the mean regional cerebral blood flow which of the activation region in primary visual cortex of occipital lobe was 32.50{+-}5.67%. The significant activation sites using a statistical parameter of brain constructed a rendering image and image fusion with SPECT and MRI. Visual activation was revealed significant increase through quantitative analysis in visual cortex. Activation region was certified in Talairach coordinate and primary visual cortex (Ba17),visual association area (Ba18,19) of Brodmann.

Quantitative evaluation of regional cerebral blood flow by visual stimulation in {sup 99m}Tc-HMPAO brain SPECT

Energy Technology Data Exchange (ETDEWEB)

Juh, R. H.; Suh, T. S.; Chung, Y. A. [The Catholic Univ., of Korea, Seoul (Korea, Republic of)

2002-07-01

The purpose of this study is to investigate the effects of visual activation and quantitative analysis of regional cerebral blood flow. Visual activation was known to increase regional cerebral blood flow in the visual cortex in occipital lobe. We evaluated that change in the distribution of 99mTc-HMPAO (Hexamethyl propylene amine oxime) to reflect in regional cerebral blood flow. The six volunteers were injected with 925 MBq (mean ages: 26.75 years, n=6, 3men, 3women) underwent MRI and 99mTc- HMPAO SPECT during a rest state with closed eyes and visual stimulated with 8 Hz LED. We delineate the region of interest and calculated the mean count per voxel in each of the fifteen slices to quantitative analysis. The ROI to whole brain ratio and regional index was calculated pixel to pixel subtraction visual non-activation image from visual activation image and constructed brain map using a statistical parameter map (SPM99). The mean regional cerebral blood flow was increased due to visual stimulation. The increase rate of the mean regional cerebral blood flow which of the activation region in primary visual cortex of occipital lobe was 32.50{+-}5.67%. The significant activation sites using a statistical parameter of brain constructed a rendering image and image fusion with SPECT and MRI. Visual activation was revealed significant increase through quantitative analysis in visual cortex. Activation region was certified in Talairach coordinate and primary visual cortex (Ba17),visual association area (Ba18,19) of Brodmann.

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

Energy Technology Data Exchange (ETDEWEB)

Tzourio, N.; Sutton, D. (Commissariat a l' Energie Atomique, Orsay (France). Service Hospitalier Frederic Joliot); Joliot, M. (Commissariat a l' Energie Atomique, Orsay (France). Service Hospitalier Frederic Joliot INSERM, Orsay (France)); Mazoyer, B.M. (Commissariat a l' Energie Atomique, Orsay (France). Service Hospitalier Frederic Joliot Antenne d' Information Medicale, C.H.U. Bichat, Paris (France)); Charlot, V. (Hopital Louis Mourier, Colombes (France). Service de Psychiatrie); Salamon, G. (CHU La Timone, Marseille (France). Service de Neuroradiologie)

1992-11-01

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

Reference Range of Functional Data of Gated Myocardial Perfusion SPECT by Quantitative Gated SPECT of Cedars-Sinai and 4D-MSPECT of Michigan University

Energy Technology Data Exchange (ETDEWEB)

Kang, Do Young; Kim, Moo Hyun; Kim, Young Dae [College of Medicine, Univ. of Donga, Pusan (Korea, Republic of)

2003-07-01

Various programs have been developed for gating of myocardial perfusion SPECT. Among the those program, the most popular program is the Quantitative Gated SPECT (QGS)? developed by Cedars-Sinai hospital and most recently released program is 4D-MSPECT? developed by university of Michigan. It is important to know the reference range of the functional data of gated myocardial perfusion SPECT because it is necessary to determine abnormality of individual patient and echocardiographic data is different from those of gated SPECT. Tc-99m MIBI gated myocardial perfusion SPECT image was reconstructed by dual head gamma camera (Siemens, BCAM, esoft) as routine procedure and analyzed using QGS? and 4D-MSPECT? program. All patients (M: F=9: 18, Age 69{+-}9 yrs) showed normal myocardial perfusion. The patients with following characteristics were excluded: previous angina or MI history, ECG change with Q wave or ST-T change, diabetes melitius, hypercholesterolemia, typical chest pain, hypertension and cardiomyopathy. Pre-test likelihood of all patients was low. (1) In stress gated SPECT by QGS?, EDV was 73{+-}25 ml, ESV 25{+-}14 ml, EF 67{+-}11 % and area of first frame of gating 106.4{+-}21cm{sup 2}. In rest gated SPECT, EDV was 76{+-}26 ml, ESV 27{+-}15 ml, EF 66{+-}12 and area of first frame of gating 108{+-}20cm{sup 2}. (2) In stress gated SPECT by 4D-MSPECT?, EDV was 76{+-}28 ml, ESV 23{+-}16 ml, EF 72{+-}11 %, mass 115{+-}24 g and ungated volume 42{+-}15 ml. In rest gated SPECT, EDV was 75{+-}27 ml, ESV 23{+-}12 ml, EF 71{+-}9%, mass 113{+-}25g and ungate dvolume 42{+-}15 ml, (3) s-EDV, s-EF, r-ESV and r-EF were significantly different between QGS? and 4D-MSPECT? (each p=0.016, p<0.001. p=0.003 and p=0.001). We determined the normal reference range of functional parameters by QGS? and 4D-MSPECT? program to diagnose individually the abnormality of patients. And the reference ranges have to adopted to be patients by each specific gating program.

Co-registered perfusion SPECT/CT: Utility for prediction of improved postoperative outcome in lung volume reduction surgery candidates

International Nuclear Information System (INIS)

Takenaka, Daisuke; Ohno, Yoshiharu; Koyama, Hisanobu; Nogami, Munenobu; Onishi, Yumiko; Matsumoto, Keiko; Yoshikawa, Takeshi; Matsumoto, Sumiaki; Sugimura, Kazuro

2010-01-01

Purpose: To directly compare the capabilities of perfusion scan, SPECT, co-registered SPECT/CT, and quantitatively and qualitatively assessed MDCT (i.e. quantitative CT and qualitative CT) for predicting postoperative clinical outcome for lung volume reduction surgery (LVRS) candidates. Materials and methods: Twenty-five consecutive candidates (19 men and six women, age range: 42-72 years) for LVRS underwent preoperative CT and perfusion scan with SPECT. Clinical outcome of LVRS for all subjects was also assessed by determining the difference between pre- and postoperative forced expiratory volume in 1 s (FEV 1 ) and 6-min walking distance (6MWD). All SPECT examinations were performed on a SPECT scanner, and co-registered to thin-section CT by using commercially available software. On planar imaging, SPECT and SPECT/CT, upper versus lower zone or lobe ratios (U/Ls) were calculated from regional uptakes between upper and lower lung fields in the operated lung. On quantitatively assessed CT, U/L for all subjects was assessed from regional functional lung volumes. On qualitatively assessed CT, planar imaging, SPECT and co-registered SPECT/CT, U/Ls were assessed with a 4-point visual scoring system. To compare capabilities of predicting clinical outcome, each U/L was statistically correlated with the corresponding clinical outcome. Results: Significantly fair or moderate correlations were observed between quantitatively and qualitatively assessed U/Ls obtained with all four methods and clinical outcomes (-0.60 ≤ r ≤ -0.42, p < 0.05). Conclusion: Co-registered perfusion SPECT/CT has better correlation with clinical outcome in LVRS candidates than do planar imaging, SPECT or qualitatively assessed CT, and is at least as valid as quantitatively assessed CT.

Co-registered perfusion SPECT/CT: Utility for prediction of improved postoperative outcome in lung volume reduction surgery candidates

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Takenaka, Daisuke [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017 (Japan); Ohno, Yoshiharu, E-mail: yosirad@kobe-u.ac.j [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017 (Japan); Koyama, Hisanobu [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017 (Japan); Nogami, Munenobu [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017 (Japan); Division of Image-Based Medicine, Institute of Biomedical Research and Innovation, 2-2, Minatojima Minamimachi Chuo-ku, Kobe, Hyogo, 650-0047 (Japan); Onishi, Yumiko [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017 (Japan); Matsumoto, Keiko [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017 (Japan); Department of Radiology, University of Yamanashi, 1110 Shimogato, Chuo, Yamanashi, 409-3898 (Japan); Yoshikawa, Takeshi; Matsumoto, Sumiaki; Sugimura, Kazuro [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017 (Japan)

2010-06-15

Purpose: To directly compare the capabilities of perfusion scan, SPECT, co-registered SPECT/CT, and quantitatively and qualitatively assessed MDCT (i.e. quantitative CT and qualitative CT) for predicting postoperative clinical outcome for lung volume reduction surgery (LVRS) candidates. Materials and methods: Twenty-five consecutive candidates (19 men and six women, age range: 42-72 years) for LVRS underwent preoperative CT and perfusion scan with SPECT. Clinical outcome of LVRS for all subjects was also assessed by determining the difference between pre- and postoperative forced expiratory volume in 1 s (FEV{sub 1}) and 6-min walking distance (6MWD). All SPECT examinations were performed on a SPECT scanner, and co-registered to thin-section CT by using commercially available software. On planar imaging, SPECT and SPECT/CT, upper versus lower zone or lobe ratios (U/Ls) were calculated from regional uptakes between upper and lower lung fields in the operated lung. On quantitatively assessed CT, U/L for all subjects was assessed from regional functional lung volumes. On qualitatively assessed CT, planar imaging, SPECT and co-registered SPECT/CT, U/Ls were assessed with a 4-point visual scoring system. To compare capabilities of predicting clinical outcome, each U/L was statistically correlated with the corresponding clinical outcome. Results: Significantly fair or moderate correlations were observed between quantitatively and qualitatively assessed U/Ls obtained with all four methods and clinical outcomes (-0.60 {<=} r {<=} -0.42, p < 0.05). Conclusion: Co-registered perfusion SPECT/CT has better correlation with clinical outcome in LVRS candidates than do planar imaging, SPECT or qualitatively assessed CT, and is at least as valid as quantitatively assessed CT.

Hybrid SPECT/CT imaging in neurology.

Science.gov (United States)

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

2014-01-01

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

Benign versus malignant osseous lesions in spine: differentiation by means of bone SPECT/CT fused image

International Nuclear Information System (INIS)

Yao Zhiming; Qu Wanying

2004-01-01

This study compared the efficiency of SPECT-CT fused image with planar bone scan, bone SPECT and CT in differentiating malignant from benign lesions and detecting metastases to the spine. Methods. Total 144 patients with spinal lesions underwent planar bone scan (WB), single photon tomography (SPECT), CT and SPECT-CT fused image by a SPECT/CT system. The malignant or benign nature of lesions was proved by radiological Methods, histological findings, 6-24 month follow-up, or all of these. The diagnostic results was divided into 4 types, i.e., normal, benign, doubtful malignant and malignant. Results. There were 137 malignant and 252 benign lesions in 144 patients, respectively. The percentages of doubtful malignant diagnosed by WB, SPECT, CT and fused image are 22.6%, 5.1%, 9.5% and 0%, respectively, p < 0.01-0.001, except for the comparison between the percentages of SPECT and CT. Sensitivities in detection of malignant lesions by WB, SPECT, CT and fused image are 75.2%, 94.2%, 96.6% and 99.3%, respectively, P < 0.001, excepting for the comparisons between those of SPECT and CT, and between those of CT and fused image. The sensitivities m detection of benign lesions by WB, SPECT, CT and fused image are, 56.7%, 86.5%, 90.1% and 96.8%, respectively, P < 0.005 - 0.001, excepting for the comparison between those of SPECT and CT. The specificities in detection of maliganant lesions by WB, SPECT, CT and fused image are 70.6%, 88.9%, 97.2% and 97.6%, respectively, P < 0.001, excepting for the comparison between those of CT and fused image. Conclusion. Bone SPECT-CT fused image has highest diagnostic and differentiating diagnostic values in detection of spinal abnormalities over the planar bone scanning and SPECT. The CT by present SPECT/CT system can complement planar bone scanning and SPECT and is clinically valuable in detection of spinal abnormalities. (authors)

A new reconstruction strategy for image improvement in pinhole SPECT

International Nuclear Information System (INIS)

Zeniya, Tsutomu; Watabe, Hiroshi; Kim, Kyeong Min; Teramoto, Noboru; Hayashi, Takuya; Iida, Hidehiro; Aoi, Toshiyuki; Sohlberg, Antti; Kudo, Hiroyuki

2004-01-01

Pinhole single-photon emission computed tomography (SPECT) is able to provide information on the biodistribution of several radioligands in small laboratory animals, but has limitations associated with non-uniform spatial resolution or axial blurring. We have hypothesised that this blurring is due to incompleteness of the projection data acquired by a single circular pinhole orbit, and have evaluated a new strategy for accurate image reconstruction with better spatial resolution uniformity. A pinhole SPECT system using two circular orbits and a dedicated three-dimensional ordered subsets expectation maximisation (3D-OSEM) reconstruction method were developed. In this system, not the camera but the object rotates, and the two orbits are at 90 and 45 relative to the object's axis. This system satisfies Tuy's condition, and is thus able to provide complete data for 3D pinhole SPECT reconstruction within the whole field of view (FOV). To evaluate this system, a series of experiments was carried out using a multiple-disk phantom filled with 99m Tc solution. The feasibility of the proposed method for small animal imaging was tested with a mouse bone study using 99m Tc-hydroxymethylene diphosphonate. Feldkamp's filtered back-projection (FBP) method and the 3D-OSEM method were applied to these data sets, and the visual and statistical properties were examined. Axial blurring, which was still visible at the edge of the FOV even after applying the conventional 3D-OSEM instead of FBP for single-orbit data, was not visible after application of 3D-OSEM using two-orbit data. 3D-OSEM using two-orbit data dramatically reduced the resolution non-uniformity and statistical noise, and also demonstrated considerably better image quality in the mouse scan. This system may be of use in quantitative assessment of bio-physiological functions in small animals. (orig.)

The impact of exercise myocardial perfusion SPECT imaging on the selection of patients for coronary angiography

International Nuclear Information System (INIS)

Song Liping; He Zuoxiang; Liu Xiujie; Shi Rongfang; Liu Yunzhong; Tian Yueqin; Zhang Xiaoli; Qin Xuewen; Chen Jilin; Gao Runlin

2001-01-01

Objective: Exercise 99 Tc m -MIBI myocardial perfusion SPECT is accurate for the diagnosis of coronary artery disease (CAD). This study assessed the impact of exercise myocardial perfusion imaging on the selection of patients for coronary angiography. Methods: 2188 consecutive patients who underwent exercise myocardial perfusion SPECT in authors' department in 1999 were retrospectively analyzed. Among them, 1807 were men, 381 women (average age: 53.5 +- 7.2 years). Overall, exercise myocardial SPECT was normal in 1731 patients, abnormal in 359 cases, and equivocal in 98 patients. There were 141 patients who underwent CAG within 60 days after myocardial SPECT. Results: Overall, 12% of the patients with abnormal SPECT imaging underwent coronary angiography, but only 5% of the patients with a normal SPECT imaging did (P < 0.001). Among these 141 patients who underwent coronary angiography, significant coronary stenosis was present in 91% of the patients who had had an abnormal SPECT imaging, but only 8% of those who had had a normal SPECT imaging (P < 0.001). In those patients who underwent coronary angiography, revascularization rate was 25% for the patients with abnormal SPECT imaging, but only 1% for the patients with a normal SPECT imaging. Conclusion: The results of exercise myocardial perfusion SPECT have a significant impact on the selection of patients for coronary angiography and revascularization

Adaptive Angular Sampling for SPECT Imaging

OpenAIRE

Li, Nan; Meng, Ling-Jian

2011-01-01

This paper presents an analytical approach for performing adaptive angular sampling in single photon emission computed tomography (SPECT) imaging. It allows for a rapid determination of the optimum sampling strategy that minimizes image variance in regions-of-interest (ROIs). The proposed method consists of three key components: (a) a set of close-form equations for evaluating image variance and resolution attainable with a given sampling strategy, (b) a gradient-based algor...

Influence of void on image quality of industrial SPECT

International Nuclear Information System (INIS)

Park, J G; Jung, S H; Kim, J B; Moon, J; Kim, C H

2013-01-01

Industrial single photon emission computed tomography (SPECT) is a promising technique to determine the dynamic behavior of industrial process media and has been developed in the Korea Atomic Energy Research Institute. The present study evaluated the influence of a void, which is presence in multiphase reactors of industrial process, on the image quality of an industrial SPECT. The results are very encouraging; that is, the performance of the industrial SPECT system is little influenced by the presence of a void, which means that industrial SPECT is an appropriate tool to estimate the dynamic characteristics of the process media in a water-air phase bubble column with a static gas sparger

Quantitative multimodality imaging in cancer research and therapy.

Science.gov (United States)

Yankeelov, Thomas E; Abramson, Richard G; Quarles, C Chad

2014-11-01

Advances in hardware and software have enabled the realization of clinically feasible, quantitative multimodality imaging of tissue pathophysiology. Earlier efforts relating to multimodality imaging of cancer have focused on the integration of anatomical and functional characteristics, such as PET-CT and single-photon emission CT (SPECT-CT), whereas more-recent advances and applications have involved the integration of multiple quantitative, functional measurements (for example, multiple PET tracers, varied MRI contrast mechanisms, and PET-MRI), thereby providing a more-comprehensive characterization of the tumour phenotype. The enormous amount of complementary quantitative data generated by such studies is beginning to offer unique insights into opportunities to optimize care for individual patients. Although important technical optimization and improved biological interpretation of multimodality imaging findings are needed, this approach can already be applied informatively in clinical trials of cancer therapeutics using existing tools. These concepts are discussed herein.

IQ-SPECT for thallium-201 myocardial perfusion imaging: effect of normal databases on quantification.

Science.gov (United States)

Konishi, Takahiro; Nakajima, Kenichi; Okuda, Koichi; Yoneyama, Hiroto; Matsuo, Shinro; Shibutani, Takayuki; Onoguchi, Masahisa; Kinuya, Seigo

2017-07-01

Although IQ-single-photon emission computed tomography (SPECT) provides rapid acquisition and attenuation-corrected images, the unique technology may create characteristic distribution different from the conventional imaging. This study aimed to compare the diagnostic performance of IQ-SPECT using Japanese normal databases (NDBs) with that of the conventional SPECT for thallium-201 ( 201 Tl) myocardial perfusion imaging (MPI). A total of 36 patients underwent 1-day 201 Tl adenosine stress-rest MPI. Images were acquired with IQ-SPECT at approximately one-quarter of the standard time of conventional SPECT. Projection data acquired with the IQ-SPECT system were reconstructed via an ordered subset conjugate gradient minimizer method with or without scatter and attenuation correction (SCAC). Projection data obtained using the conventional SPECT were reconstructed via a filtered back projection method without SCAC. The summed stress score (SSS) was calculated using NDBs created by the Japanese Society of Nuclear Medicine working group, and scores were compared between IQ-SPECT and conventional SPECT using the acquisition condition-matched NDBs. The diagnostic performance of the methods for the detection of coronary artery disease was also compared. SSSs were 6.6 ± 8.2 for the conventional SPECT, 6.6 ± 9.4 for IQ-SPECT without SCAC, and 6.5 ± 9.7 for IQ-SPECT with SCAC (p = n.s. for each comparison). The SSS showed a strong positive correlation between conventional SPECT and IQ-SPECT (r = 0.921 and p IQ-SPECT with and without SCAC was also good (r = 0.907 and p IQ-SPECT without SCAC; and 88.5, 86.8, and 87.3%, respectively, for IQ-SPECT with SCAC, respectively. The area under the curve obtained via receiver operating characteristic analysis were 0.77, 0.80, and 0.86 for conventional SPECT, IQ-SPECT without SCAC, and IQ-SPECT with SCAC, respectively (p = n.s. for each comparison). When appropriate NDBs were used, the diagnostic performance of 201 Tl IQ-SPECT

Added Value of 3D Cardiac SPECT/CTA Fusion Imaging in Patients with Reversible Perfusion Defect on Myocardial Perfusion SPECT

Energy Technology Data Exchange (ETDEWEB)

Kong, Eun Jung; Cho, Ihn Ho [Yeungnam University Hospital, Daegu (Korea, Republic of); Kang, Won Jun [Yonsei University Hospital, Seoul (Korea, Republic of); Kim, Seong Min [Chungnam National University Medical School and Hospital, Daejeon (Korea, Republic of); Won, Kyoung Sook [Keomyung University Dongsan Hospital, Daegu (Korea, Republic of); Lim, Seok Tae [Chonbuk National University Medical School and Hospital, Jeonju (Korea, Republic of); Hwang, Kyung Hoon [Gachon University Gil Hospital, Incheon (Korea, Republic of); Lee, Byeong Il; Bom, Hee Seung [Chonnam National University Medical School and Hospital, Gwangju (Korea, Republic of)

2009-12-15

Integration of the functional information of myocardial perfusion SPECT (MPS) and the morphoanatomical information of coronary CT angiography (CTA) may provide useful additional diagnostic information of the spatial relationship between perfusion defects and coronary stenosis. We studied to know the added value of three dimensional cardiac SPECT/CTA fusion imaging (fusion image) by comparing between fusion image and MPS. Forty-eight patients (M:F=26:22, Age: 63.3{+-}10.4 years) with a reversible perfusion defect on MPS (adenosine stress/rest SPECT with Tc-99m sestamibi or tetrofosmin) and CTA were included. Fusion images were molded and compared with the findings from the MPS. Invasive coronary angiography served as a reference standard for fusion image and MPS. Total 144 coronary arteries in 48 patients were analyzed; Fusion image yielded the sensitivity, specificity, negative and positive predictive value for the detection of hemodynamically significant stenosis per coronary artery 82.5%, 79.3%, 76.7% and 84.6%, respectively. Respective values for the MPS were 68.8%, 70.7%, 62.1% and 76.4%. And fusion image also could detect more multi-vessel disease. Fused three dimensional volume-rendered SPECT/CTA imaging provides intuitive convincing information about hemodynamic relevant lesion and could improved diagnostic accuracy.

Optimization of SPECT-CT Hybrid Imaging Using Iterative Image Reconstruction for Low-Dose CT: A Phantom Study.

Directory of Open Access Journals (Sweden)

Oliver S Grosser

Full Text Available Hybrid imaging combines nuclear medicine imaging such as single photon emission computed tomography (SPECT or positron emission tomography (PET with computed tomography (CT. Through this hybrid design, scanned patients accumulate radiation exposure from both applications. Imaging modalities have been the subject of long-term optimization efforts, focusing on diagnostic applications. It was the aim of this study to investigate the influence of an iterative CT image reconstruction algorithm (ASIR on the image quality of the low-dose CT images.Examinations were performed with a SPECT-CT scanner with standardized CT and SPECT-phantom geometries and CT protocols with systematically reduced X-ray tube currents. Analyses included image quality with respect to photon flux. Results were compared to the standard FBP reconstructed images. The general impact of the CT-based attenuation maps used during SPECT reconstruction was examined for two SPECT phantoms. Using ASIR for image reconstructions, image noise was reduced compared to FBP reconstructions for the same X-ray tube current. The Hounsfield unit (HU values reconstructed by ASIR were correlated to the FBP HU values(R2 ≥ 0.88 and the contrast-to-noise ratio (CNR was improved by ASIR. However, for a phantom with increased attenuation, the HU values shifted for low X-ray tube currents I ≤ 60 mA (p ≤ 0.04. In addition, the shift of the HU values was observed within the attenuation corrected SPECT images for very low X-ray tube currents (I ≤ 20 mA, p ≤ 0.001.In general, the decrease in X-ray tube current up to 30 mA in combination with ASIR led to a reduction of CT-related radiation exposure without a significant decrease in image quality.

State-of-the-art of small animal imaging with high-resolution SPECT

International Nuclear Information System (INIS)

Nikolaus, S.; Wirrwar, A.; Antke, C.; Kley, K.; Mueller, H.W.

2005-01-01

During the recent years, in vivo imaging of small animals using SPECT has become of growing relevance. Along with the development of dedicated high-resolution small animal SPECT cameras, an increasing number of conventional clinical scanners has been equipped with single or multipinhole collimators. This paper reviews the small animal tomographs, which are operating at present and compares their performance characteristics. Furthermore, we describe the in vivo imaging studies, which have been performed so far with the individual scanners and survey current approaches to optimize molecular imaging with small animal SPECT. (orig.)

DMSA SPECT imaging using oblique reconstruction in a paediatric population - benefits and technical considerations

International Nuclear Information System (INIS)

Parsons, G.; Ford, M.; Crisp, J.; Bernard, E.; Howman-Giles, R.

1997-01-01

Full text: DMSA renal scans are frequently requested for the diagnosis and follow-up of acute pyelonephritis and cortical scarring. This study was designed to:- 1. evaluate oblique reconstruction of DMSA SPECT over standard plane reconstruction and planar imaging; and 2. report on the technical aspects important in obtaining high quality DMSA SPECT, particularly in neonates. Over seven months, 210/231 (91 %) of DMSA scans were performed with SPECT on children from age nine days to 16 years, the median age being 2.5 years. 65 patients (31 %) were under one year and 39 (18%) were under six months. Planar and SPECT imaging with standard plane reconstruction and oblique reorientation was performed on the Siemens triple-headed gamma camera. High quality SPECT images were obtained on the smallest babies using a paediatric palette, and were of comparable quality to those of older children. At the time of reporting, the nuclear medicine physician assessed the diagnostic value of the three types of date presented: (1) planar images; (2) standard plane SPECT reconstruction; and (3) oblique SPECT reconstruction. Cortical defects were identified separately for upper, middle and lower poles. Three physicians concluded that high quality SPECT is superior to planar images when assessing the renal cortex. In addition, oblique reorientation is superior to standard reconstruction, particularly at the upper and lower poles. SPECT is now performed routinely on patients of all ages, and the oblique sagittal and coronal reorientation is now used in place of the standard reconstruction

Feasibility of a CdTe-based SPECT for high-resolution low-dose small animal imaging: a Monte Carlo simulation study

International Nuclear Information System (INIS)

Park, S-J; Yu, A R; Lee, Y-J; Kim, Y-S; Kim, H-J

2014-01-01

Dedicated single-photon-emission computed tomography (SPECT) systems based on pixelated semiconductors such as cadmium telluride (CdTe) are in development to study small animal models of human disease. In an effort to develop a high-resolution, low-dose system for small animal imaging, we compared a CdTe-based SPECT system and a conventional NaI(Tl)-based SPECT system in terms of spatial resolution, sensitivity, contrast, and contrast-to-noise ratio (CNR). In addition, we investigated the radiation absorbed dose and calculated a figure of merit (FOM) for both SPECT systems. Using the conventional NaI(Tl)-based SPECT system, we achieved a spatial resolution of 1.66 mm at a 30 mm source-to-collimator distance, and a resolution of 2.4-mm hot-rods. Using the newly-developed CdTe-based SPECT system, we achieved a spatial resolution of 1.32 mm FWHM at a 30 mm source-to-collimator distance, and a resolution of 1.7-mm hot-rods. The sensitivities at a 30 mm source-to-collimator distance were 115.73 counts/sec/MBq and 83.38 counts/sec/MBq for the CdTe-based SPECT and conventional NaI(Tl)-based SPECT systems, respectively. To compare quantitative measurements in the mouse brain, we calculated the CNR for images from both systems. The CNR from the CdTe-based SPECT system was 4.41, while that from the conventional NaI(Tl)-based SPECT system was 3.11 when the injected striatal dose was 160 Bq/voxel. The CNR increased as a function of injected dose in both systems. The FOM of the CdTe-based SPECT system was superior to that of the conventional NaI(Tl)-based SPECT system, and the highest FOM was achieved with the CdTe-based SPECT at a dose of 40 Bq/voxel injected into the striatum. Thus, a CdTe-based SPECT system showed significant improvement in performance compared with a conventional system in terms of spatial resolution, sensitivity, and CNR, while reducing the radiation dose to the small animal subject. Herein, we discuss the feasibility of a CdTe-based SPECT system for high

Evaluation of image reconstruction methods for 123I-MIBG-SPECT. A rank-order study

International Nuclear Information System (INIS)

Soederberg, Marcus; Mattsson, Soeren; Oddstig, Jenny; Uusijaervi-Lizana, Helena; Leide-Svegborn, Sigrid; Valind, Sven; Thorsson, Ola; Garpered, Sabine; Prautzsch, Tilmann; Tischenko, Oleg

2012-01-01

Background: There is an opportunity to improve the image quality and lesion detectability in single photon emission computed tomography (SPECT) by choosing an appropriate reconstruction method and optimal parameters for the reconstruction. Purpose: To optimize the use of the Flash 3D reconstruction algorithm in terms of equivalent iteration (EI) number (number of subsets times the number of iterations) and to compare with two recently developed reconstruction algorithms ReSPECT and orthogonal polynomial expansion on disc (OPED) for application on 123 I-metaiodobenzylguanidine (MIBG)-SPECT. Material and Methods: Eleven adult patients underwent SPECT 4 h and 14 patients 24 h after injection of approximately 200 MBq 123 I-MIBG using a Siemens Symbia T6 SPECT/CT. Images were reconstructed from raw data using the Flash 3D algorithm at eight different EI numbers. The images were ranked by three experienced nuclear medicine physicians according to their overall impression of the image quality. The obtained optimal images were then compared in one further visual comparison with images reconstructed using the ReSPECT and OPED algorithms. Results: The optimal EI number for Flash 3D was determined to be 32 for acquisition 4 h and 24 h after injection. The average rank order (best first) for the different reconstructions for acquisition after 4 h was: Flash 3D 32 > ReSPECT > Flash 3D 64 > OPED, and after 24 h: Flash 3D 16 > ReSPECT > Flash 3D 32 > OPED. A fair level of inter-observer agreement concerning optimal EI number and reconstruction algorithm was obtained, which may be explained by the different individual preferences of what is appropriate image quality. Conclusion: Using Siemens Symbia T6 SPECT/CT and specified acquisition parameters, Flash 3D 32 (4 h) and Flash 3D 16 (24 h), followed by ReSPECT, were assessed to be the preferable reconstruction algorithms in visual assessment of 123 I-MIBG images

Effect of attenuation by the cranium on quantitative SPECT measurements of cerebral blood flow and a correction method

International Nuclear Information System (INIS)

Iwase, Mikio; Kurono, Kenji; Iida, Akihiko.

1998-01-01

Attenuation correction for cerebral blood flow SPECT image reconstruction is usually performed by considering the head as a whole to be equivalent to water, and the effects of differences in attenuation between subjects produced by the cranium have not been taken into account. We determined the differences in attenuation between subjects and assessed a method of correcting quantitative cerebral blood flow values. Attenuations by head on the right and left sides were measured before intravenous injection of 123 I-IMP, and water-converted diameters of both sides (Ta) were calculated from the measurements obtained. After acquiring SPECT images, attenuation correction was conducted according to the method of Sorenson, and images were reconstructed. The diameters of the right and left sides in the same position as the Ta (Tt) were calculated from the contours determined by threshold values. Using Ts given by 2 Ts=Ta-Tt, the correction factor λ=exp(μ 1 Ts) was calculated and multiplied as the correction factor when rCBF was determined. The results revealed significant differences between Tt and Ta. Although no gender differences were observed in Tt, they were seen in both Ta and Ts. Thus, interindividual differences in attenuation by the cranium were found to have an influence that cannot be ignored. Inter-subject correlation is needed to obtain accurate quantitative values. (author)

An efficient algorithm for reconstruction of spect images in the presence of spatially varying attenuation

International Nuclear Information System (INIS)

Zeeberg, B.R.; Bacharach, S.; Carson, R.; Green, M.V.; Larson, S.M.; Soucaille, J.F.

1985-01-01

An algorithm is presented which permits the reconstruction of SPECT images in the presence of spatially varying attenuation. The algorithm considers the spatially variant attenuation as a perturbation of the constant attenuation case and computes a reconstructed image and a correction image to estimate the effects of this perturbation. The corrected image will be computed from these two images and is of comparable quality both visually and quantitatively to those simulated for zero or constant attenuation taken as standard reference images. In addition, the algorithm is time efficient, in that the time required is approximately 2.5 times that for a standard convolution-back projection algorithm

Quantitative evaluation of right ventricular overload in cor pulmonale using 201Tl myocardial SPECT

International Nuclear Information System (INIS)

Kato, Hiroshi; Misawa, Toshihiro; Kutsumi, Yasunori

1991-01-01

To determine quantitatively the discriminant and characteristics of cor pulmonale, 201 Tl myocardial perfusion SPECT was performed in 16 patients with chronic obstructive pulmonary disease (COPD) and 7 with restrictive pulmonary disease (RPD). One section of the short-axis SPECT image in which the right ventricle was most clearly visualized was selected. Tl-score was defined as the ratio of the sum of counts in the region of interest (ROI) at the anterior, mid, and posterior regions of the right ventricular free wall to the sum of counts in ROI at the posterior, lateral, and anterior walls of the left ventricle, and the anterior and posterior regions of the interventricular septum. In the group of COPD patients, Tl-score was positively correlated with mean pulmonary arterial pressure (mPAP), total pulmonary vascular resistance (TPR), and arterial carbon dioxide tension (PaCO 2 ), while it was inversely correlated with arterial oxygen tension (PaO 2 ). However, there was no significant correlation between Tl-score and mPAP, TPR, PaCO 2 , and PaO 2 in the group of RPD patients. In assessing pulmonary hypertension as defined by mPAP over 20 mmHg, a Tl-score greater than 0.25 was useful with a sensitivity of 69% and a specificity of 90%. The occurrence of cor pulmonale is a major factor in determining the prognosis of COPD patients. It was concluded that 201 Tl myocardial SPECT is useful for evaluating right ventricular overload quantitatively, as well as for assessing core pulmonale, especially in COPD patients, since the ratio of Tl counts in the right and left ventricles was significantly correlated with right cardiopulmonary hemodynamic parameters. (N.K.)

Quantitative Nuclear Medicine Imaging: Concepts, Requirements and Methods

Energy Technology Data Exchange (ETDEWEB)

NONE

2014-01-15

The absolute quantification of radionuclide distribution has been a goal since the early days of nuclear medicine. Nevertheless, the apparent complexity and sometimes limited accuracy of these methods have prevented them from being widely used in important applications such as targeted radionuclide therapy or kinetic analysis. The intricacy of the effects degrading nuclear medicine images and the lack of availability of adequate methods to compensate for these effects have frequently been seen as insurmountable obstacles in the use of quantitative nuclear medicine in clinical institutions. In the last few decades, several research groups have consistently devoted their efforts to the filling of these gaps. As a result, many efficient methods are now available that make quantification a clinical reality, provided appropriate compensation tools are used. Despite these efforts, many clinical institutions still lack the knowledge and tools to adequately measure and estimate the accumulated activities in the human body, thereby using potentially outdated protocols and procedures. The purpose of the present publication is to review the current state of the art of image quantification and to provide medical physicists and other related professionals facing quantification tasks with a solid background of tools and methods. It describes and analyses the physical effects that degrade image quality and affect the accuracy of quantification, and describes methods to compensate for them in planar, single photon emission computed tomography (SPECT) and positron emission tomography (PET) images. The fast paced development of the computational infrastructure, both hardware and software, has made drastic changes in the ways image quantification is now performed. The measuring equipment has evolved from the simple blind probes to planar and three dimensional imaging, supported by SPECT, PET and hybrid equipment. Methods of iterative reconstruction have been developed to allow for

The clinical application of SPECT myocardial perfusion imaging with 99mTc-MIBI

International Nuclear Information System (INIS)

Dong Weiyu

1992-01-01

This paper reported 182 SPECT myocardial perfusion images with China made 99m Tc-MIBI and were compared with ECG and UCG. The sensitivity of SPECT in ischemic were 91.2% and was higher than ECG (74.9%)and UCG (61.8%) (P < 0.01). And its specificity, accuracy and positive predictive rate were 78.3%, 90% and 97% respectively. Besides 9 cases have reverse distribution after exercise and rest images. In some ICD patients had shown their SPECT images, the perfusion defects in exercise as well as in rest image

SPECT/CT imaging in children with papillary thyroid carcinoma

International Nuclear Information System (INIS)

Kim, Hwa-Young; Gelfand, Michael J.; Sharp, Susan E.

2011-01-01

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

Improvements in SPECT technology for cerebral imaging

International Nuclear Information System (INIS)

Esser, P.D.

1985-01-01

Advancement in three major areas of SPECT (single photon emission computed tomography) technology have resulted in improved image quality for cerebral studies. In the first area, single-crystal camera electronics, extensive use of microprocessors, custom digital circuitry, an data bus architecture have allowed precise external control of all gantry motions and improved signal processing. The new digital circuitry permits energy, uniformity, and linearity corrections to be an integral part of the processing electronics. Calibration of these correlations is controlled by algorithms stored in the camera's memory. The second area of improved SPECT technology is camera collimation and related imaging techniques. In this area, system resolution has been improved without loss of sensitivity by decreasing the air gap between patient and collimator surface. Since cerebral studies characteristically image high-contrast regions less than 1 cm in size, image quality has been improved by increasing collimator resolution even at the expense of sensitivity. Increased resolution also improved image contrast for studies using 123 I-labeled pharmaceuticals with 3% to 4% 124 I contamination. 65 references

Technetium SPECT agents for imaging heart and brain

International Nuclear Information System (INIS)

Linder, K.E.

1990-01-01

One major goal of radiopharmaceutical research has been the development of technetium-based perfusion tracers for SPECT imaging of the heart and brain. The recent clinical introduction of the technetium complexes HM-PAO, ECD and DMG-2MP for brain imaging, and of CDO-MEB and MIBI for heart imaging promises to revolutionize the field of nuclear medicine. All of these agents appear to localize in the target tissue in proportion to blood flow, but their mechanisms of localization and/or retention may differ quite widely. In this talk, a survey of the new technetium SPECT agents will be presented. The inorganic and biological chemistry of these complexes, mechanisms of uptake and retention, QSAR studies, and potential clinical applications are discussed

Bull's-eye map of myocardial perfusion MR imaging. Comparison with SPECT

International Nuclear Information System (INIS)

Nomura, Yukihiro; Nanjo, Shuji; Yamazaki, Junichi; Yoshikawa, Kohki; Inoue, Yusuke

2003-01-01

When diagnosing heart disease, chest roentgenograms, ultrasonography, single-photon emission computed tomography (SPECT), and coronary arteriography are usually performed. Magnetic resonance (MR) imaging is not widely used for evaluating heart disease. Recent technological progress has allowed high quality images of the heart to be reliably obtained. A routine MR study taking about 30-40 minutes can provide a large amount of diagnostic information, such as cardiac structure, function, perfusion, and myocardial viability. The analysis software that can offer Bull's-eye maps from myocardial perfusion images has recently become commercially available. In this study, the characteristics of Bull's-eye mapping of MR imaging is compared with that of Bull's-eye mapping of SPECT using the same heart phantom. The difference in the image quality of the Bull's-eye maps was evaluated among the receiver coils of MR imaging. On Bull's-eye maps from both MR imaging and SPECT, decreased signal intensity was noted in the posterolateral wall. The degree of decrease in the signal of the MR imaging was more prominent than of SPECT. The decrease was severe for the general-purpose receive-only flexible (GPFLEX) coil, moderate for the cardiac and TORSO coil, and slight for the body coil. In the selection of a coil, it is necessary to take into consideration the trade-off between the distribution of signal intensity and the signal-to-noise ratio (SNR). (author)

Metabolic imaging using SPECT

International Nuclear Information System (INIS)

Taki, Junichi; Matsunari, Ichiro

2007-01-01

In normal condition, the heart obtains more than two-thirds of its energy from the oxidative metabolism of long chain fatty acids, although a wide variety of substrates such as glucose, lactate, ketone bodies and amino acids are also utilised. In ischaemic myocardium, on the other hand, oxidative metabolism of free fatty acid is suppressed and anaerobic glucose metabolism plays a major role in residual oxidative metabolism. Therefore, metabolic imaging can be an important technique for the assessment of various cardiac diseases and conditions. In SPECT, several iodinated fatty acid traces have been introduced and studied. Of these, 123 I-labelled 15-(p-iodophenyl)3-R, S-methylpentadecanoic acid (BMIPP) has been the most commonly used tracer in clinical studies, especially in some of the European countries and Japan. In this review article, several fatty acid tracers for SPECT are characterised, and the mechanism of uptake and clinical utility of BMIPP are discussed in detail. (orig.)

Y-90 SPECT ML image reconstruction with a new model for tissue-dependent bremsstrahlung production using CT information: a proof-of-concept study

Science.gov (United States)

Lim, Hongki; Fessler, Jeffrey A.; Wilderman, Scott J.; Brooks, Allen F.; Dewaraja, Yuni K.

2018-06-01

While the yield of positrons used in Y-90 PET is independent of tissue media, Y-90 SPECT imaging is complicated by the tissue dependence of bremsstrahlung photon generation. The probability of bremsstrahlung production is proportional to the square of the atomic number of the medium. Hence, the same amount of activity in different tissue regions of the body will produce different numbers of bremsstrahlung photons. Existing reconstruction methods disregard this tissue-dependency, potentially impacting both qualitative and quantitative imaging of heterogeneous regions of the body such as bone with marrow cavities. In this proof-of-concept study, we propose a new maximum-likelihood method that incorporates bremsstrahlung generation probabilities into the system matrix, enabling images of the desired Y-90 distribution to be reconstructed instead of the ‘bremsstrahlung distribution’ that is obtained with existing methods. The tissue-dependent probabilities are generated by Monte Carlo simulation while bone volume fractions for each SPECT voxel are obtained from co-registered CT. First, we demonstrate the tissue dependency in a SPECT/CT imaging experiment with Y-90 in bone equivalent solution and water. Visually, the proposed reconstruction approach better matched the true image and the Y-90 PET image than the standard bremsstrahlung reconstruction approach. An XCAT phantom simulation including bone and marrow regions also demonstrated better agreement with the true image using the proposed reconstruction method. Quantitatively, compared with the standard reconstruction, the new method improved estimation of the liquid bone:water activity concentration ratio by 40% in the SPECT measurement and the cortical bone:marrow activity concentration ratio by 58% in the XCAT simulation.

In vivo regional quantitation of intrathoracic /sup 99m/Tc using SPECT: concise communication

International Nuclear Information System (INIS)

Osborne, D.; Jaszczak, R.; Coleman, R.E.; Greer, K.; Lischko, M.

1982-01-01

A whole-body single-photon emission computed tomographic system (SPECT) was used to quantitate the activities of a series of /sup 99m/Tc point sources in the dog's thorax and to evaluate attenuation of a uniform esophageal line source containing a known concentration of /sup 99m/Tc. A first-order attenuation correction and an empirically derived attenuation coefficient of 0.09 cm-1 were used in the SPECT analyses of the intrathoracic point sources. The relationship between SPECT measurements of multiple point-source activities and the same sources measured in air was linear over a range of 100 to 1000 muCi (slope 1.08; R2 coefficient of determination 0.97). These data are sufficiently accurate to allow an estimate of the regional activity of radiopharmaceutical in the dog's thorax and justify their use in experimental quantitation of regional pulmonary perfusion

In vivo quantification of {sup 177}Lu with planar whole-body and SPECT/CT gamma camera imaging

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Bailey, Dale L. [Department of Nuclear Medicine, Royal North Shore Hospital, St Leonards, NSW 2065 (Australia); Faculty of Health Sciences, University of Sydney, Cumberland, NSW (Australia); Sydney Medical School, University of Sydney, Camperdown, NSW (Australia); NETwork, Sydney Vital, St Leonards, Sydney, NSW (Australia); Hennessy, Thomas M.; Willowson, Kathy P.; Henry, E. Courtney [Institute of Medical Physics, University of Sydney, Camperdown, NSW (Australia); Chan, David L.H. [Department of Nuclear Medicine, Royal North Shore Hospital, St Leonards, NSW 2065 (Australia); NETwork, Sydney Vital, St Leonards, Sydney, NSW (Australia); Aslani, Alireza [Department of Nuclear Medicine, Royal North Shore Hospital, St Leonards, NSW 2065 (Australia); Roach, Paul J. [Department of Nuclear Medicine, Royal North Shore Hospital, St Leonards, NSW 2065 (Australia); Sydney Medical School, University of Sydney, Camperdown, NSW (Australia)

2015-09-17

Advances in gamma camera technology and the emergence of a number of new theranostic radiopharmaceutical pairings have re-awakened interest in in vivo quantification with single-photon-emitting radionuclides. We have implemented and validated methodology to provide quantitative imaging of {sup 177}Lu for 2D whole-body planar studies and for 3D tomographic imaging with single-photon emission computed tomography (SPECT)/CT. Whole-body planar scans were performed on subjects to whom a known amount of [{sup 177}Lu]-DOTA-octreotate had been administered for therapy. The total radioactivity estimated from the images was compared with the known amount of the radionuclide therapy administered. In separate studies, venous blood samples were withdrawn from subjects after administration of [{sup 177}Lu]-DOTA-octreotate while a SPECT acquisition was in progress and the concentration of the radionuclide in the venous blood sample compared with that estimated from large blood pool structures in the SPECT reconstruction. The total radioactivity contained within an internal SPECT calibration standard was also assessed. In the whole-body planar scans (n = 28), the estimated total body radioactivity was accurate to within +4.6 ± 5.9 % (range −17.1 to +11.2 %) of the correct value. In the SPECT reconstructions (n = 12), the radioactivity concentration in the cardiac blood pool was accurate to within −4.0 ± 7.8 % (range −16.1 to +7.5 %) of the true value and the internal standard measurements (n = 89) were within 2.0 ± 8.5 % (range −16.3 to +24.2 %) of the known amount of radioactivity contained. In our hands, state-of-the-art hybrid SPECT/CT gamma cameras were able to provide accurate estimates of in vivo radioactivity to better than, on average, ±10 % for use in biodistribution and radionuclide dosimetry calculations.

Study of a simple method and software for quantitative measurement of rCBF with 99Tcm-ECD SPECT brain imaging

International Nuclear Information System (INIS)

Shu Boxue; Lai Huaan; Li Zhigang; Shi An

2000-01-01

Objective: To create a simple, practical, stable and easy to popularize rCBF quantitative measurement method. Methods: 1) Creating attenuation correction factor (δ) of brain; 2) Proving a factor (ρ) between planar image and tomographic image; 3) Creating SPECT system to determine the dead time and to correct linear regression equation; 4) Measuring lung retardation rate (R 1 ); 5) Improving Nickel model and editing the software; 6) Clinical application; The modified method was performed in 24 subjects, including 15 healthy controls, 8 patients with epilepsy in intermission and 1 patient with brain infarction. Results: δ = 1.7, ρ = 2.23, R 1 -1 ·100 g -1 . The rCBFs of foci in 8 cases of epilepsy were obviously decreased, (22.5∼34.2) mL·min -1 ·100 g -1 , and in the case of brain infarction was only 7.2 mL·min -1 ·100 g -1 . Conclusions: The method is reliable, practical and easy to perform with good quality control. Overall, it is of high clinical value

Activity concentration measurements using a conjugate gradient (Siemens xSPECT) reconstruction algorithm in SPECT/CT.

Science.gov (United States)

Armstrong, Ian S; Hoffmann, Sandra A

2016-11-01

The interest in quantitative single photon emission computer tomography (SPECT) shows potential in a number of clinical applications and now several vendors are providing software and hardware solutions to allow 'SUV-SPECT' to mirror metrics used in PET imaging. This brief technical report assesses the accuracy of activity concentration measurements using a new algorithm 'xSPECT' from Siemens Healthcare. SPECT/CT data were acquired from a uniform cylinder with 5, 10, 15 and 20 s/projection and NEMA image quality phantom with 25 s/projection. The NEMA phantom had hot spheres filled with an 8 : 1 activity concentration relative to the background compartment. Reconstructions were performed using parameters defined by manufacturer presets available with the algorithm. The accuracy of activity concentration measurements was assessed. A dose calibrator-camera cross-calibration factor (CCF) was derived from the uniform phantom data. In uniform phantom images, a positive bias was observed, ranging from ∼6% in the lower count images to ∼4% in the higher-count images. On the basis of the higher-count data, a CCF of 0.96 was derived. As expected, considerable negative bias was measured in the NEMA spheres using region mean values whereas positive bias was measured in the four largest NEMA spheres. Nonmonotonically increasing recovery curves for the hot spheres suggested the presence of Gibbs edge enhancement from resolution modelling. Sufficiently accurate activity concentration measurements can easily be measured on images reconstructed with the xSPECT algorithm without a CCF. However, the use of a CCF is likely to improve accuracy further. A manual conversion of voxel values into SUV should be possible, provided that the patient weight, injected activity and time between injection and imaging are all known accurately.

Combined visual and semi-quantitative assessment of 123I-FP-CIT SPECT for the diagnosis of dopaminergic neurodegenerative diseases.

Science.gov (United States)

Ueda, Jun; Yoshimura, Hajime; Shimizu, Keiji; Hino, Megumu; Kohara, Nobuo

2017-07-01

Visual and semi-quantitative assessments of 123 I-FP-CIT single-photon emission computed tomography (SPECT) are useful for the diagnosis of dopaminergic neurodegenerative diseases (dNDD), including Parkinson's disease, dementia with Lewy bodies, progressive supranuclear palsy, multiple system atrophy, and corticobasal degeneration. However, the diagnostic value of combined visual and semi-quantitative assessment in dNDD remains unclear. Among 239 consecutive patients with a newly diagnosed possible parkinsonian syndrome who underwent 123 I-FP-CIT SPECT in our medical center, 114 patients with a disease duration less than 7 years were diagnosed as dNDD with the established criteria or as non-dNDD according to clinical judgment. We retrospectively examined their clinical characteristics and visual and semi-quantitative assessments of 123 I-FP-CIT SPECT. The striatal binding ratio (SBR) was used as a semi-quantitative measure of 123 I-FP-CIT SPECT. We calculated the sensitivity and specificity of visual assessment alone, semi-quantitative assessment alone, and combined visual and semi-quantitative assessment for the diagnosis of dNDD. SBR was correlated with visual assessment. Some dNDD patients with a normal visual assessment had an abnormal SBR, and vice versa. There was no statistically significant difference between sensitivity of the diagnosis with visual assessment alone and semi-quantitative assessment alone (91.2 vs. 86.8%, respectively, p = 0.29). Combined visual and semi-quantitative assessment demonstrated superior sensitivity (96.7%) to visual assessment (p = 0.03) or semi-quantitative assessment (p = 0.003) alone with equal specificity. Visual and semi-quantitative assessments of 123 I-FP-CIT SPECT are helpful for the diagnosis of dNDD, and combined visual and semi-quantitative assessment shows superior sensitivity with equal specificity.

Triangular SPECT system for 3-D total organ volume imaging: Design concept and preliminary imaging results

International Nuclear Information System (INIS)

Lim, C.B.; Anderson, J.; Covic, J.

1985-01-01

SPECT systems based on 2-D detectors for projection data collection and filtered back-projection image reconstruction have the potential for true 3-D imaging, providing contiguous slice images in any orientation. Anger camera-based SPECT systems have the natural advantage supporting planar imaging clinical procedures. However, current systems suffer from two drawbacks; poor utilization of emitted photons, and inadequate system design for SPECT. A SPECT system consisting of three rectangular cameras with radial translation would offer the variable cylindrical FOV of 25 cm to 40 cm diameter allowing close detector access to the object. This system would provide optimized imaging for both brain and body organs in terms of sensitivity and resolution. For brain imaging a tight detector triangle with fan beam collimation, matching detector UFOV to the head, allows full 2 π utilization of emitted photons, resulting in >4 times sensitivity increase over the single detector system. Minification of intrinsic detector resolution in fan beam collimation further improves system resolution. For body organ imaging the three detectors with parallel hole collimators, rotating in non-circular orbit, provide both improved resolution and three-fold sensitivity increase. Practical challenges lie in ensuring perfect image overlap from three detectors without resolution degradation and artifact generation in order to benefit from the above improvements. An experimental system has been developed to test the above imaging concept and we have successfully demonstrated the superior image quality of the overlapped images. Design concept will be presented with preliminary imaging results

Infective endocarditis detection through SPECT/CT images digital processing

Science.gov (United States)

Moreno, Albino; Valdés, Raquel; Jiménez, Luis; Vallejo, Enrique; Hernández, Salvador; Soto, Gabriel

2014-03-01

Infective endocarditis (IE) is a difficult-to-diagnose pathology, since its manifestation in patients is highly variable. In this work, it was proposed a semiautomatic algorithm based on SPECT images digital processing for the detection of IE using a CT images volume as a spatial reference. The heart/lung rate was calculated using the SPECT images information. There were no statistically significant differences between the heart/lung rates values of a group of patients diagnosed with IE (2.62+/-0.47) and a group of healthy or control subjects (2.84+/-0.68). However, it is necessary to increase the study sample of both the individuals diagnosed with IE and the control group subjects, as well as to improve the images quality.

Rest delayed images on 99mTc-MIBI myocardial SPECT as a noninvasive screen for the diagnosis of vasospastic angina pectoris

International Nuclear Information System (INIS)

Ono, Soichi; Yamaguchi, Hiroyuki; Takayama, Shin; Kurabe, Atsushi; Heito, Takayuki

2002-01-01

Diagnostic usefulness of 99m Tc-hexakis-2-methoxy isobutyl isonitrile (MIBI) myocardial SPECT at rest was examined in 39 cases of coronary vasospastic angina pectoris who were diagnosed by a positive reaction to ergonovine provocation. SPECT was performed 45 minutes (early image) and 3 hours (delayed image) after the intravenous injection of approximately 600 MBq of MIBI. Decrease in accumulation was ranked by four defect scores (0: normal; 1: slight decrease; 2: moderate decrease; 3: severe decrease) and the total defect score was evaluated semiquantitatively. The washout rate between the normal area and the spasm area was also evaluated quantitatively using bull's eye. As a result, 15 cases (15/39; 38.4%) showed decreased accumulation in the early image and 27 cases (27/39; 69.2%) showed decreased accumulation in the delayed image. All of the cases which showed decreased accumulation in the early image had decreased accumulation in the delayed image as well. In 6 cases (6/34; 17.6%) showed ST wave changes during exercise ECG and 16 cases (16/34: 47%) showed decreased accumulation in the exercise myocardial SPECT. The washout rate of MIBI in the decreased accumulation area was significantly higher than that of the normal area. Of 32 ergonovine induced vasospastic area, 23 areas (72%) exhibited decreased accumulation in the delayed image for the same area. Decreased accumulation in the delayed image in MIBI was due to the enhanced washout, which, in turn, indicated declined retention of MIBI by mitochondrial membrane. In coronary vasospastic angina pectoris, spasm induced ischemia was thought to have an effect on the mitochondria. This study suggested that even with a normal exercise ECG and exercise myocardial SPECT, there's a strong possibility of coronary vasospastic angina pectoris if a decreased accumulation was found in the delayed image in the MIBI myocardial SPECT at rest. Hence, in diagnosing coronary vasospastic angina pectoris, the delayed image in the

Scatter and attenuation correction in SPECT

International Nuclear Information System (INIS)

Ljungberg, Michael

2004-01-01

The adsorbed dose is related to the activity uptake in the organ and its temporal distribution. Measured count rate with scintillation cameras is related to activity through the system sensitivity, cps/MBq. By accounting for physical processes and imaging limitations we can measure the activity at different time points. Correction for physical factor, such as attenuation and scatter is required for accurate quantitation. Both planar and SPECT imaging can be used to estimate activities for radiopharmaceutical dosimetry. Planar methods have been the most widely used but is a 2D technique. With accurate modelling for imagine in iterative reconstruction, SPECT methods will prove to be more accurate

Functional brain imaging study in patients with anxiety disorders using SPECT

International Nuclear Information System (INIS)

Sun Da; Zhan Hongwei; Liu Hongbiao; Li Huichun

2005-01-01

Objective: To evaluate the changes of brain function in patients with anxiety disorders. Methods: Regional cerebral perfusion was investigated using SPECT in 65 patients with anxiety disorders dragnosed according to the fourth edition of the diagnostic and statistical manual of mental disorder (DSMTD) criteria and in a matched control group of 21 healthy volunteers. 65 cases of the patients were further divided into: drug treated group (31 patients) and non-drug treated group (34 patients). The mean ages of the patients and the controls were (39.2±26.1) and (34.4±9.7) years, respectively. The severity of the anxiety was assessed using the 17-item Hamilton Anxiety scale (mean: 24.8±5.5 and 24.7±7.5, respectively). After administration of 740-925 MBq 99 Tc m -ethylene cysteinate direct (ECD) brain SPECT image study was performed. For the semi- quantitative analysis of the data, the ratios of the mean counts/pixel in the different cerebral regions of interest (ROI) to that of cerebellum were calculated respectively as a regional perfusion index (RPI). Some patients had a repeated SPECT after three months of treatment. Results: 93.8% (61/65) patients had relative hypoperfusions in some cerebral regions. Compared with the control group, the patients had a significant decrease of regional cerebral blood flow (rCBF) in the bilateral frontal lobes, paralimbic system, temporal lobes and basal ganglia. The course of disease had negatively correlated with the changes of rCBF in both groups of patients. Follow-up SPECT study demonstrated increased rCBF related with the symptomatic improvement. Conclusions: Patients with anxiety disorders had profound dysfunction of the frontal and temporal cortices, and was closely related to the symptom and therapy. 99 Tc m -ECD brain SPECT may offer the most accurate assessment of response to therapy. . (authors)

Thoracic and abdominal SPECT imaging in systemic amyloidosis in identifying multiorgan involvement

International Nuclear Information System (INIS)

Wellman, H.N.; Benson, M.D.; Park, H.M.; Siddiqui, A.R.; Krepshaw, J.D.

1988-01-01

Thirty-three patients with systemic amyloidosis have been studied. Thoracic single photon emission computed tomography (SPECT) for myocardial involvement and skeletal imaging were performed with Tc-99m PYP, and abdominal SPECT with TcS colloid. Myocardial wall involvement was easily discernible with SPECT in 17 cases, and in many with normal ultrasonography. PYP uptake was also observed in liver (five patients), kidneys (four patients), and soft tissues (two patients). Most patients had widespread degenerative joint disease. With TcS colloid, intrinsic liver abnormalities were found in four patients, hepatomegaly in seven, and splenic infiltration in two. Nuclear SPECT and planar imaging characterize the distribution of systemic amyloidosis in organs, distribution not readily identified with other diagnostic modalities

Impact of SPECT/CT in imaging inflammation and infection; Wertigkeit der SPECT/CT fuer die nuklearmedizinische Entzuendungsdiagnostik

Energy Technology Data Exchange (ETDEWEB)

Linke, R. [Klinikum Bremen-Mitte, Bremen (Germany). Klinik fuer Nuklearmedizin; Kuwert, T. [Erlangen-Nuernberg Univ., Erlangen (Germany). Nuklearmedizinische Klinik mit Poliklinik

2011-03-15

Even today infection remains a significant concern, and the diagnosis and localization of infectious foci is an important health issue. As an established infection-imaging modality, nuclear medicine plays a vital health-care role in the diagnosis and subsequent effective treatment of this condition. Several techniques in nuclear medicine significantly aid infection diagnosis, including triple-phase bone scanning, {sup 18}F-FDG-PET and imaging with {sup 111}In-oxine-, {sup 99m}Tc-HMPAO-labeled leukocytes. Each radiopharmaceutical has specific advantages and disadvantages that makes it suitable to diagnose different infectious processes (e.g., soft-tissue sepsis, inflammatory bowel disease, osteomyelitis, occult fever, fever of unknown origin, and infections commonly found in immuno-compromised patients). However, their clinical applications may be limited by the relatively low spatial resolution and the lack of anatomic landmarks of a highly specific tracer with only scarce background uptake to use as a framework for orientation. Anatomic imaging modalities such as CT provide a high-quality assessment of structural abnormalities related to infection, but these structural abnormalities may be unspecific. Furthermore, to detect infection before anatomical changes are present, functional imaging could have some advantages over anatomical imaging. Scintigraphic studies have demonstrated high sensitivity and specificity to an infectious process. Diagnosis and precise delineation of infection may be challenging in certain clinical scenarios, rendering decisions concerning further patient management difficult. The SPECT/CT-technology combines the acquisition of SPECT and CT data with the same imaging device enabling perfect overlay of anatomical and functional images. SPECT/CT imaging data has been shown to be beneficial for many clinical settings such as indeterminate findings in bone scintigraphy, orthopaedic disorders, endocrine, and neuroendocrine tumors. Therefore

Two-dimensional filtering of SPECT images using the Metz and Wiener filters

International Nuclear Information System (INIS)

King, M.A.; Schwinger, R.B.; Penney, B.C.; Doherty, P.W.

1984-01-01

Presently, single photon emission computed tomographic (SPECT) images are usually reconstructed by arbitrarily selecting a one-dimensional ''window'' function for use in reconstruction. A better method would be to automatically choose among a family of two-dimensional image restoration filters in such a way as to produce ''optimum'' image quality. Two-dimensional image processing techniques offer the advantages of a larger statistical sampling of the data for better noise reduction, and two-dimensional image deconvolution to correct for blurring during acquisition. An investigation of two such ''optimal'' digital image restoration techniques (the count-dependent Metz filter and the Wiener filter) was made. They were applied both as two-dimensional ''window'' functions for preprocessing SPECT images, and for filtering reconstructed images. Their performance was compared by measuring image contrast and per cent fractional standard deviation (% FSD) in multiple-acquisitions of the Jaszczak SPECT phantom at two different count levels. A statistically significant increase in image contrast and decrease in % FSD was observed with these techniques when compared to the results of reconstruction with a ramp filter. The adaptability of the techniques was manifested in a lesser % reduction in % FSD at the high count level coupled with a greater enhancement in image contrast. Using an array processor, processing time was 0.2 sec per image for the Metz filter and 3 sec for the Wiener filter. It is concluded that two-dimensional digital image restoration with these techniques can produce a significant increase in SPECT image quality

Evaluation of image reconstruction methods for {sup 123}I-MIBG-SPECT. A rank-order study

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Soederberg, Marcus; Mattsson, Soeren; Oddstig, Jenny; Uusijaervi-Lizana, Helena; Leide-Svegborn, Sigrid [Medical Radiation Physics, Dept. of Clinical Sciences Malmoe, Lund Univ., Skaane Univ. Hospital, Malmoe (Sweden)], e-mail: marcus.soderberg@med.lu.se; Valind, Sven; Thorsson, Ola; Garpered, Sabine [Dept. of Clinical Physiology, Skaane Univ. Hospital, Malmoe (Sweden); Prautzsch, Tilmann [Scivis wissenschaftlice Bildverarbeitung GmbH, Goettingen (Germany); Tischenko, Oleg [Research Unit Medical Radiation Physics and Diagnostics (AMSD), Helmholtz Zentrum Muenchen (Germany); German Research Center for Environmental Health, Neuherberg (Germany)

2012-09-15

Background: There is an opportunity to improve the image quality and lesion detectability in single photon emission computed tomography (SPECT) by choosing an appropriate reconstruction method and optimal parameters for the reconstruction. Purpose: To optimize the use of the Flash 3D reconstruction algorithm in terms of equivalent iteration (EI) number (number of subsets times the number of iterations) and to compare with two recently developed reconstruction algorithms ReSPECT and orthogonal polynomial expansion on disc (OPED) for application on {sup 123}I-metaiodobenzylguanidine (MIBG)-SPECT. Material and Methods: Eleven adult patients underwent SPECT 4 h and 14 patients 24 h after injection of approximately 200 MBq {sup 123}I-MIBG using a Siemens Symbia T6 SPECT/CT. Images were reconstructed from raw data using the Flash 3D algorithm at eight different EI numbers. The images were ranked by three experienced nuclear medicine physicians according to their overall impression of the image quality. The obtained optimal images were then compared in one further visual comparison with images reconstructed using the ReSPECT and OPED algorithms. Results: The optimal EI number for Flash 3D was determined to be 32 for acquisition 4 h and 24 h after injection. The average rank order (best first) for the different reconstructions for acquisition after 4 h was: Flash 3D{sub 32} > ReSPECT > Flash 3D{sub 64} > OPED, and after 24 h: Flash 3D{sub 16} > ReSPECT > Flash 3D{sub 32} > OPED. A fair level of inter-observer agreement concerning optimal EI number and reconstruction algorithm was obtained, which may be explained by the different individual preferences of what is appropriate image quality. Conclusion: Using Siemens Symbia T6 SPECT/CT and specified acquisition parameters, Flash 3D{sub 32} (4 h) and Flash 3D{sub 16} (24 h), followed by ReSPECT, were assessed to be the preferable reconstruction algorithms in visual assessment of {sup 123}I-MIBG images.

Reproducibility of the assessment of myocardial function using gated Tc-99m-MIBI SPECT and quantitative software

International Nuclear Information System (INIS)

Lee, Dong Soo; Cheon, Gi Jeong; Ahn, Ji Young; Jeong, Joon Ki; Lee, Myung Chul

1998-01-01

We investigated reproducibility of the quantification of left ventricular volume and ejection fraction, and grading of myocardial wall motion and systolic thickening when we used gated myocardial SPECT and Cedars quantification software. We performed gated myocardial SPECT in 33 consecutive patients twice in the same position after Tc-99m-MIBI SPECT. We used 16 frames per cycle for the gating of sequential Tc-99m-MIBI SPECT. After reconstruction, we used Cedars quantitative gated SPECT and calculated ventricular volume and ejection fraction (EF). Wall motion was graded using 5 point score. Wall thickening was graded using 4 point score. Coefficient of variation for re-examination of volume and fraction were calculated. Kappa values (k-value) for assessing reproducibility of wall motion or wall thickening were calculated. Enddiastolic volumes (EDV) ranged from 58 ml to 248 ml (122 ml +/-42 ml), endsystolic volumes (ESV) from 20 ml to 174 ml (65 ml+/-39 ml), and EF from 20% to 68% (51%+/-14%). Geometric mean of standard deviations of 33 patients was 5.0 ml for EDV, 3.9 ml for ESV and 1.9% for EF. Their average differences were not different from zero (p>0.05). k-value for wall motion using 2 consecutive images was 0.76 (confidence interval: 0.71-0.81). k-value was 0.87 (confidence interval: 0.83-0.90) for assessment of wall thickening. We concluded that quantification of functional indices, assessment of wall motion and wall thickening using gated Tc-99m MIBI SPECT was reproducible and we could use this method for the evaluation of short-acting drug effect

Semi-quantitative SPECT for anterior dislocation of the disc in the temporo-mandibular joint

Energy Technology Data Exchange (ETDEWEB)

Oesterreich, F.U.; Jend-Rossmann, I.; Jend, H.H.; Triebel, H.J.

1987-01-01

SPECT-examination of the TMJ using 99m-Tc-MDP was performed in 43 patients with arthrographically proven anterior dislocation of the disc and in 30 normals. The results were evaluated visually and also in a semi-quantitative manner that took account of relative 99m Tc activity in the TMJ and of the age of the patient. In the presence of arthrographically proven anterior, but reversible, disc dislocation, the semi-quantitative method proved positive in 75% of cases (28 cases). In joints with fixed anterior dislocation (29 cases), bone changes were demonstrated in 26%. Visual evaluation was positive in 50% of reversible, and in 72% of non-reversible dislocations. Semi-quantitative SPECT of the TMJ is excellent for demonstrating bone reaction resulting from TMJ dysfunction and for indicating the severity of the joint abnormality.

In vivo SPECT reporter gene imaging of regulatory T cells.

Directory of Open Access Journals (Sweden)

Ehsan Sharif-Paghaleh

Full Text Available Regulatory T cells (Tregs were identified several years ago and are key in controlling autoimmune diseases and limiting immune responses to foreign antigens, including alloantigens. In vivo imaging techniques including intravital microscopy as well as whole body imaging using bioluminescence probes have contributed to the understanding of in vivo Treg function, their mechanisms of action and target cells. Imaging of the human sodium/iodide symporter via Single Photon Emission Computed Tomography (SPECT has been used to image various cell types in vivo. It has several advantages over the aforementioned imaging techniques including high sensitivity, it allows non-invasive whole body studies of viable cell migration and localisation of cells over time and lastly it may offer the possibility to be translated to the clinic. This study addresses whether SPECT/CT imaging can be used to visualise the migratory pattern of Tregs in vivo. Treg lines derived from CD4(+CD25(+FoxP3(+ cells were retrovirally transduced with a construct encoding for the human Sodium Iodide Symporter (NIS and the fluorescent protein mCherry and stimulated with autologous DCs. NIS expressing self-specific Tregs were specifically radiolabelled in vitro with Technetium-99m pertechnetate ((99mTcO(4(- and exposure of these cells to radioactivity did not affect cell viability, phenotype or function. In addition adoptively transferred Treg-NIS cells were imaged in vivo in C57BL/6 (BL/6 mice by SPECT/CT using (99mTcO(4(-. After 24 hours NIS expressing Tregs were observed in the spleen and their localisation was further confirmed by organ biodistribution studies and flow cytometry analysis. The data presented here suggests that SPECT/CT imaging can be utilised in preclinical imaging studies of adoptively transferred Tregs without affecting Treg function and viability thereby allowing longitudinal studies within disease models.

Interest of hybrid SPECT-CT imaging for diagnosis of infection

International Nuclear Information System (INIS)

Riviere, A.; Farid, K.; Guyot, M.; Jeandot, R.; Allard, M.; Fernandez, P.; Clermont, H. de; Dauchy, F.; Dupon, M.; Fernandez, P.

2008-01-01

Single-Photon Emission Computed Tomography-Computerized Tomography (SPECT-CT) is a new hybrid technique which offers new diagnostic capabilities in daily nuclear medicine practice. This technique not only allows to acquire merged anatomic and functional images in the same time, but also, it increases sensitivity and accuracy of SPECT thanks to attenuation and scattering corrections got from transmission data. Until now, SPECT-CT data have been mainly obtained in oncology and cardiology, but now, many authors use it in many scan studies and particularly for infectious diseases. In inflammatory bowel diseases, SPECT-CT seems to increase diagnostic performances and to modify management of many patients. In suspected vascular sepsis, SPECT-CT could increase sensitivity of white blood cell scintigraphy but also its specificity thanks to spatial resolution of CT. In osteo-articular sepsis, SPECT-CT has the advantage to distinguish osteomyelitis from soft tissue infection and to guide biopsies. Nevertheless, in the light of PET-CT works, SPECT-CT development will probably modify nuclear medicine practice and many studies have to be conducted to highlight consensual procedure guidelines. (authors)

SPECT imaging evaluation in movement disorders: far beyond visual assessment

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Badiavas, Kosmas [General Hospital, Medical Physics Department, Thessaloniki (Greece); Molyvda, Elisavet; Psarrakos, Kyriakos [Medical Physics Dept., General Hospital, Thessaloniki (Greece); Iakovou, Ioannis; Karatzas, Nikolaos [Medical Physical Dept., Aristotle Univ., Thessaloniki (Greece); Tsolaki, Magdalini [3. Neurology Clinic, Aristotle Univ., Thessaloniki (Greece)

2011-04-15

Single photon emission computed tomography (SPECT) imaging with {sup 123}I-FP-CIT is of great value in differentiating patients suffering from Parkinson's disease (PD) from those suffering from essential tremor (ET). Moreover, SPECT with {sup 123}I-IBZM can differentiate PD from Parkinson's ''plus'' syndromes. Diagnosis is still mainly based on experienced observers' visual assessment of the resulting images while many quantitative methods have been developed in order to assist diagnosis since the early days of neuroimaging. The aim of this work is to attempt to categorize, briefly present and comment on a number of semi-quantification methods used in nuclear medicine neuroimaging. Various arithmetic indices have been introduced with region of interest (ROI) manual drawing methods giving their place to automated procedures, while advancing computer technology has allowed automated image registration, fusion and segmentation to bring quantification closer to the final diagnosis based on the whole of the patient's examinations results, clinical condition and response to therapy. The search for absolute quantification has passed through neuroreceptor quantification models, which are invasive methods that involve tracer kinetic modelling and arterial blood sampling, a practice that is not commonly used in a clinical environment. On the other hand, semi-quantification methods relying on computers and dedicated software try to elicit numerical information out of SPECT images. The application of semi-quantification methods aims at separating the different patient categories solving the main problem of finding the uptake in the structures of interest. The semi-quantification methods which were studied fall roughly into three categories, which are described as classic methods, advanced automated methods and pixel-based statistical analysis methods. All these methods can be further divided into various subcategories. The plethora of

Evaluation of crossed cerebellar diaschisis in 30 patients with major cerebral artery occlusion by means of quantitative I-123 IMP SPECT

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Miyazawa, Nobuhiko; Toyama, Keiji; Arbab, A.S.; Arai, Takao; Nukui, Hideaki [Yamanashi Medical Univ., Tamaho (Japan); Koizumi, Kiyoshi

2001-12-01

Quantitative crossed cerebellar diaschisis (CCD) and the correlation with a reduction in supratentorial regional cerebral blood flow (rCBF) and cerebrovascular reserve capacity (CVR) were investigated in clinically stable patients with major cerebral artery occlusion by the iodine-123-N-isopropyl-p-iodoamphetamine (I-123 IMP) single photon emission computed tomography (SPECT) method. Thirty patients with major cerebral artery occlusion underwent SPECT by the I-123 IMP autoradiographic method. Regional CBF was measured in the cerebral hemisphere, frontal and parietal lobes, temporo-parietal lobe, and cerebellum both at rest and after administration of acetazolamide. Eighteen of 30 patients (60%) had CCD. CCD was significantly related to magnetic resonance imaging evidence of infarction. Quantitative CCD was 17% and the CVR in the cerebellum was preserved in patients with CCD. There was a significant difference in CBF and CVR between the affected and normal sides in all regions of interest in the patients without CCD [CBF (ml/100 g/min): hemisphere (H), normal side (N): 31.4{+-}6.8, affected side (A): 27.5{+-}7.4; p<0.05. CVR: H, N: 0.56{+-}0.38, A: 0.42{+-}0.18; p<0.01]. CCD is common in patients with major cerebral artery occlusion, and quantitative I-123 IMP SPECT is helpful in detecting CCD in clinically stable patients with occlusion of major cerebral arteries. (author)

Assessment of smoking-induced impairment of pulmonary perfusion using three-dimensional SPECT images

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Miyasaka, Takashi [Toho Univ., Tokyo (Japan). School of Medicine

1997-09-01

The effects of smoking on ventilation-perfusion lung scintigrams were investigated. The subjects comprised 40 healthy males (28 smokers and 12 nonsmokers) without a history of cardiopulmonary disease and with normal chest radiographs. After acquisition of planar images of ventilation lung scintigrams with 370 MBq of {sup 133}Xe gas, planar images and SPECT images of pulmonary perfusion flow were obtained using 185 MBq of {sup 99m}Tc-MAA. Planar imaging showed perfusion defects in only 5 smokers. In contrast, 16 subjects were found to have perfusion defects on SPECT images (p<0.05), indicating the usefulness of SPECT images in detecting minor vascular damage of the lung. Although perfusion defects were common in the smokers (p<0.05), their relationship to the BRINKMAN index was uncertain. The perfusion defects found in the smokers were nonsegmental and commonly involved the right upper lobe. Ventilation scans revealed only delayed washout of {sup 133}Xe in 4 smokers, suggesting that smoking-induced abnormal perfusion on SPECT appears earlier than impaired ventilation on scintigrams. (author)

HMPAO-SPECT during epileptic seizures: Early and late images

International Nuclear Information System (INIS)

Overbeck, B.; Gruenwald, F.; Bockisch, A.; Biersack, H.J.; Reinke, U.; Gratz, K.F.

1990-01-01

For presurgical evaluation of epilepsy a 44-year old patient with complex-partial seizures underwent HMPAO-SPECT. The morphology of the seizures, the MRI-scan, psychometry and ictal as well as interictal EEGs showed a left temporal origin of the seizures. Early images were obtained 20 min and late images 24 h following injection. On both scans a marked hyperperfusion was observed in the left temporal area. A crossed cerebellar diaschisis was also seen on both SPECTs. It could be shown that during ictal examinations there is no bloodflow-dependent wash-out from brain tissue. (orig.) [de

Improvement of image quality using interpolated projection data estimation method in SPECT

International Nuclear Information System (INIS)

Takaki, Akihiro; Soma, Tsutomu; Murase, Kenya; Kojima, Akihiro; Asao, Kimie; Kamada, Shinya; Matsumoto, Masanori

2009-01-01

General data acquisition for single photon emission computed tomography (SPECT) is performed in 90 or 60 directions, with a coarse pitch of approximately 4-6 deg for a rotation of 360 deg or 180 deg, using a gamma camera. No data between adjacent projections will be sampled under these circumstances. The aim of the study was to develop a method to improve SPECT image quality by generating lacking projection data through interpolation of data obtained with a coarse pitch such as 6 deg. The projection data set at each individual degree in 360 directions was generated by a weighted average interpolation method from the projection data acquired with a coarse sampling angle (interpolated projection data estimation processing method, IPDE method). The IPDE method was applied to the numerical digital phantom data, actual phantom data and clinical brain data with Tc-99m ethyle cysteinate dimer (ECD). All SPECT images were reconstructed by the filtered back-projection method and compared with the original SPECT images. The results confirmed that streak artifacts decreased by apparently increasing a sampling number in SPECT after interpolation and also improved signal-to-noise (S/N) ratio of the root mean square uncertainty value. Furthermore, the normalized mean square error values, compared with standard images, had similar ones after interpolation. Moreover, the contrast and concentration ratios increased their effects after interpolation. These results indicate that effective improvement of image quality can be expected with interpolation. Thus, image quality and the ability to depict images can be improved while maintaining the present acquisition time and image quality. In addition, this can be achieved more effectively than at present even if the acquisition time is reduced. (author)

Pixel based statistical analysis of differences between lung SPECT images: methodological aspects

International Nuclear Information System (INIS)

Bendada, S.; Rocchisani, J.L.M.; Moretti, J.L.

2002-01-01

The statistical parametric mapping method is applied in Neurology for activation studies. We had adapted this powerful method on Lungs SPECT to help for the diagnosis and the follow-up of pulmonary embolism and other lung diseases. The SPECT slices of pairs of examination were normalized thanks to the total acquired counts, reconstruction background subtracted, smoothed and realigned. A parametric image of statistical differences was finally computed. We had thus obtained a 3D image showing regions of improved or altered region under treatment. A tuning of the various parameters could lead to more accurate image. This new approach of lung SPECT processing appears to be a promising useful tool for the physician. (author)

Establishment study of the in vivo imaging analysis with small animal imaging modalities (micro-PET and micro-SPECT/CT) for bio-drug development

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Jang, Beomsu; Park, Sanghyeon; Park, Jeonghoon; Jo, Sungkee; Jung, Uhee; Kim, Seolwha; Lee, Yunjong; Choi, Daeseong

2011-01-15

In this study, we established the image acquisition and analysis procedures of micro-PET, SPECT/CT using the experimental animal (mouse) for the development of imaging assessment method for the bio-drug. We examined the micro-SPECT/CT, PET imaging study using the Siemens Inveon micro-multimodality system (SPECT/CT) and micro-PET with {sup 99m}Tc-MDP, DMSA, and {sup 18}F-FDG. SPECT imaging studies using 3 types of pinhole collimators. 5-MWB collimator was used for SPECT image study. To study whole-body distribution, {sup 99m}Tc-MDP SPECT image study was performed. We obtained the fine distribution image. And the CT images was obtained to provide the anatomical information. And then these two types images are fused. To study specific organ uptake, we examined {sup 99}mTc-DMSA SPECT/CT imaging study. We also performed the PET image study using U87MG tumor bearing mice and {sup 18}F-FDG. The overnight fasting, warming and anesthesia with 2% isoflurane pretreatment enhance the tumor image through reducing the background uptake including brown fat, harderian gland and skeletal muscles. Also we got the governmental approval for use of x-ray generator for CT and radioisotopes as sealed and open source. We prepared the draft of process procedure for the experimental animal imaging facility. These research results can be utilized as a basic image study protocols and data for the image assessment of drugs including biological drug.

Establishment study of the in vivo imaging analysis with small animal imaging modalities (micro-PET and micro-SPECT/CT) for bio-drug development

International Nuclear Information System (INIS)

Jang, Beomsu; Park, Sanghyeon; Park, Jeonghoon; Jo, Sungkee; Jung, Uhee; Kim, Seolwha; Lee, Yunjong; Choi, Daeseong

2011-01-01

In this study, we established the image acquisition and analysis procedures of micro-PET, SPECT/CT using the experimental animal (mouse) for the development of imaging assessment method for the bio-drug. We examined the micro-SPECT/CT, PET imaging study using the Siemens Inveon micro-multimodality system (SPECT/CT) and micro-PET with 99m Tc-MDP, DMSA, and 18 F-FDG. SPECT imaging studies using 3 types of pinhole collimators. 5-MWB collimator was used for SPECT image study. To study whole-body distribution, 99m Tc-MDP SPECT image study was performed. We obtained the fine distribution image. And the CT images was obtained to provide the anatomical information. And then these two types images are fused. To study specific organ uptake, we examined 99 mTc-DMSA SPECT/CT imaging study. We also performed the PET image study using U87MG tumor bearing mice and 18 F-FDG. The overnight fasting, warming and anesthesia with 2% isoflurane pretreatment enhance the tumor image through reducing the background uptake including brown fat, harderian gland and skeletal muscles. Also we got the governmental approval for use of x-ray generator for CT and radioisotopes as sealed and open source. We prepared the draft of process procedure for the experimental animal imaging facility. These research results can be utilized as a basic image study protocols and data for the image assessment of drugs including biological drug

Effects of cross talk on dual energy SPECT imaging between 123I-BMIPP and 201Tl

International Nuclear Information System (INIS)

Morita, Masato; Narita, Hitoshi; Yamamoto, Juro; Fukutake, Naoshige; Ohyanagi, Mitsumasa; Iwasaki, Tadaaki; Fukuchi, Minoru

1994-01-01

The study was undertaken to determine how much cross talk influences the visual assessment of dual energy single photon emission computed tomographic (SPECT) images with iodine 123 beta-methyl-p-iodophenylpentadecanoic acid (I-123 BMIPP) and thallium-201 in 15 patients with acute myocardial infarction. After single SPECT with I-123 BMIPP was undertaken, simultaneous dual SPECT with I-123 BMIPP and Tl-201 were undertaken in all patients. Three patients also underwent single SPECT with Tl-201. I-123 BMIPP and Tl-201 uptake was graded in four-score for the comparison between single and dual SPECT images. There was good correlation between dual energy SPECT and both single I-123 BMIPP SPECT (pS=0.97) and single Tl-201 SPECT (pS=0.59). Uptake scores were increased on dual energy SPECT, compared with single I-123 SPECT (8 out of 132 segments) and single Tl-201 SPECT (12 out of 36 segments). Overall, there was a comparatively well correlation between single SEPCT with either I-123 BMIPP or Tl-201 and dual energy SPECT images. However, one tracer uptake sometimes increased in the other tracer defect areas. This was noticeable when I-123 BMIPP exerted an effect on Tl-201. (N.K.)

SPECT/CT image fusion with 99mTc-HYNIC-TOC in the oncological diagnostic

International Nuclear Information System (INIS)

Haeusler, F.

2006-07-01

Neuroendocrine tumours displaying somatostatin receptors have been successfully visualized with somatostatin receptor imaging. The aim of this retrospective study was to evaluate the value of anatomical-functional image fusion. Image fusion means the combined transmission and emission tomography (computed tomography (CT)) and single-photon emission computed tomography (SPECT) ) and was analyzed in comparison with SPECT and CT alone. Fifty-three patients (30 men and 23 women; mean age 55,9 years; range: 20-82 years) with suspected or known endocrine tumours were studied. The patients were referred to image fusion because of staging of newly diagnosed tumours (14) or biochemically/clinically suspected neuroendocrine tumour (20) or follow-up studies after therapy (19). The patients were studied with SPECT at 2 and 4 hours after injection of 400 MBq of 99mTc-EDDA-HYNIC-Tyr3-octreotide using a dual-detector scintillation camera. The CT was performed on one of the following two days. For both investigations the patients were fixed in an individualized vacuum mattress to guarantee exactly the same position. SPECT and SPECT/CT showed an equivalent scan result in 35 patients (66 %), discrepancies were found in 18 cases (34 %). After image fusion the scan result was true-positive in 27 patients ( 50.9 %) and true-negative in 25 patients (47.2 %). One patient with multiple small liver metastases escaped SPECT as well as image fusion and was so false-negative. The frequency of equivocal and probable lesion characterization was reduced by 11.6% (12 to 0) with PET/CT in comparison with PET or CT alone. The frequency of definite lesion characterization was increased by 11.6% (91 to 103). SPECT/CT affected the clinical management in 21 patients (40 %). The results of this study indicate that SPECT/CT is a valuable tool for the assessment of neuroendocrine tumours. SPECT/CT is better than SPECT or CT alone and it allows a more precise staging and determination of prognosis and

Comparison of planar images and SPECT with bayesean preprocessing for the demonstration of facial anatomy and craniomandibular disorders

International Nuclear Information System (INIS)

Kircos, L.T.; Ortendahl, D.A.; Hattner, R.S.; Faulkner, D.; Taylor, R.L.

1984-01-01

Craniomandiublar disorders involving the facial anatomy may be difficult to demonstrate in planar images. Although bone scanning is generally more sensitive than radiography, facial bone anatomy is complex and focal areas of increased or decreased radiotracer may become obscured by overlapping structures in planar images. Thus SPECT appears ideally suited to examination of the facial skeleton. A series of patients with craniomandibular disorders of unknown origin were imaged using 20 mCi Tc-99m MDP. Planar and SPECT (Siemens 7500 ZLC Orbiter) images were obtained four hours after injection. The SPECT images were reconstructed with a filtered back-projection algorithm. In order to improve image contrast and resolution in SPECT images, the rotation views were pre-processed with a Bayesean deblurring algorithm which has previously been show to offer improved contrast and resolution in planar images. SPECT images using the pre-processed rotation views were obtained and compared to the SPECT images without pre-processing and the planar images. TMJ arthropathy involving either the glenoid fossa or the mandibular condyle, orthopedic changes involving the mandible or maxilla, localized dental pathosis, as well as changes in structures peripheral to the facial skeleton were identified. Bayesean pre-processed SPECT depicted the facial skeleton more clearly as well as providing a more obvious demonstration of the bony changes associated with craniomandibular disorders than either planar images or SPECT without pre-processing

[Application of GVF snake model in segmentation of whole body bone SPECT image].

Science.gov (United States)

Zhu, Chunmei; Tian, Lianfang; Chen, Ping; Wang, Lifei; Ye, Guangchun; Mao, Zongyuan

2008-02-01

Limited by the imaging principle of whole body bone SPECT image, the gray value of bladder area is quite high, which affects the image's brightness, contrast and readability. In the meantime, the similarity between bladder area and focus makes it difficult for some images to be segmented automatically. In this paper, an improved Snake model, GVF Snake, is adopted to automatically segment bladder area, preparing for further processing of whole body bone SPECT images.

Stereotactic imaging for radiotherapy: accuracy of CT, MRI, PET and SPECT

International Nuclear Information System (INIS)

Karger, Christian P; Hipp, Peter; Henze, Marcus; Echner, Gernot; Hoess, Angelika; Schad, Lothar; Hartmann, Guenther H

2003-01-01

CT, MRI, PET and SPECT provide complementary information for treatment planning in stereotactic radiotherapy. Stereotactic correlation of these images requires commissioning tests to confirm the localization accuracy of each modality. A phantom was developed to measure the accuracy of stereotactic localization for CT, MRI, PET and SPECT in the head and neck region. To this end, the stereotactically measured coordinates of structures within the phantom were compared with their mechanically defined coordinates. For MRI, PET and SPECT, measurements were performed using two different devices. For MRI, T1- and T2-weighted imaging sequences were applied. For each measurement, the mean radial deviation in space between the stereotactically measured and mechanically defined position of target points was determined. For CT, the mean radial deviation was 0.4 ± 0.2 mm. For MRI, the mean deviations ranged between 0.7 ± 0.2 mm and 1.4 ± 0.5 mm, depending on the MRI device and the imaging sequence. For PET, mean deviations of 1.1 ± 0.5 mm and 2.4 ± 0.3 mm were obtained. The mean deviations for SPECT were 1.6 ± 0.5 mm and 2.0 ± 0.6 mm. The phantom is well suited to determine the accuracy of stereotactic localization with CT, MRI, PET and SPECT in the head and neck region. The obtained accuracy is well below the physical resolution for CT, PET and SPECT, and of comparable magnitude for MRI. Since the localization accuracy may be device dependent, results obtained at one device cannot be generalized to others

Quantitative spectral K-edge imaging in preclinical photon-counting x-ray computed tomography.

Science.gov (United States)

de Vries, Anke; Roessl, Ewald; Kneepkens, Esther; Thran, Axel; Brendel, Bernhard; Martens, Gerhard; Proska, Roland; Nicolay, Klaas; Grüll, Holger

2015-04-01

The objective of this study was to investigate the feasibility and the accuracy of spectral computed tomography (spectral CT) to determine the tissue concentrations and localization of high-attenuation, iodine-based contrast agents in mice. Iodine tissue concentrations determined with spectral CT are compared with concentrations measured with single-photon emission computed tomography (SPECT) and inductively coupled plasma mass spectrometry (ICP-MS). All animal procedures were performed according to the US National Institutes of Health principles of laboratory animal care and were approved by the ethical review committee of Maastricht, The Netherlands. Healthy Swiss mice (n = 4) were injected with an iodinated emulsion radiolabeled with indium as multimodal contrast agent for CT and SPECT. The CT and SPECT scans were acquired using a dedicated small-animal SPECT/CT system. Subsequently, scans were performed with a preclinical spectral CT scanner equipped with a photon-counting detector and 6 energy threshold levels. Quantitative data analysis of SPECT and spectral CT scans were obtained using 3-dimensional volumes-of-interest drawing methods. The ICP-MS on dissected organs was performed to determine iodine uptake per organ and was compared with the amounts determined from spectral CT and SPECT. Iodine concentrations obtained with image-processed spectral CT data correlated well with data obtained either with noninvasive SPECT imaging (slope = 0.96, r = 0.75) or with ICP-MS (slope = 0.99, r = 0.89) in tissue samples. This preclinical proof-of-concept study shows the in vivo quantification of iodine concentrations in tissues using spectral CT. Our multimodal imaging approach with spectral CT and SPECT using radiolabeled iodinated emulsions together with ICP-based quantification allows a direct comparison of all methods. Benchmarked against ICP-MS data, spectral CT in the present implementation shows a slight underestimation of organ iodine concentrations compared

High-resolution brain SPECT imaging by combination of parallel and tilted detector heads.

Science.gov (United States)

Suzuki, Atsuro; Takeuchi, Wataru; Ishitsu, Takafumi; Morimoto, Yuichi; Kobashi, Keiji; Ueno, Yuichiro

2015-10-01

To improve the spatial resolution of brain single-photon emission computed tomography (SPECT), we propose a new brain SPECT system in which the detector heads are tilted towards the rotation axis so that they are closer to the brain. In addition, parallel detector heads are used to obtain the complete projection data set. We evaluated this parallel and tilted detector head system (PT-SPECT) in simulations. In the simulation study, the tilt angle of the detector heads relative to the axis was 45°. The distance from the collimator surface of the parallel detector heads to the axis was 130 mm. The distance from the collimator surface of the tilted detector heads to the origin on the axis was 110 mm. A CdTe semiconductor panel with a 1.4 mm detector pitch and a parallel-hole collimator were employed in both types of detector head. A line source phantom, cold-rod brain-shaped phantom, and cerebral blood flow phantom were evaluated. The projection data were generated by forward-projection of the phantom images using physics models, and Poisson noise at clinical levels was applied to the projection data. The ordered-subsets expectation maximization algorithm with physics models was used. We also evaluated conventional SPECT using four parallel detector heads for the sake of comparison. The evaluation of the line source phantom showed that the transaxial FWHM in the central slice for conventional SPECT ranged from 6.1 to 8.5 mm, while that for PT-SPECT ranged from 5.3 to 6.9 mm. The cold-rod brain-shaped phantom image showed that conventional SPECT could visualize up to 8-mm-diameter rods. By contrast, PT-SPECT could visualize up to 6-mm-diameter rods in upper slices of a cerebrum. The cerebral blood flow phantom image showed that the PT-SPECT system provided higher resolution at the thalamus and caudate nucleus as well as at the longitudinal fissure of the cerebrum compared with conventional SPECT. PT-SPECT provides improved image resolution at not only upper but also at

Application of SPECT/CT imaging in the diagnosis of benign diseases

International Nuclear Information System (INIS)

Garcheva, M.; Demirev, A.

2014-01-01

The application of recently introduced hybrid nuclear medicine methods gains importance in a variety of clinical fields, mainly because of the unique combination between functional and anatomical data provided by those methods and their capability for a precise localization of pathological processes. Single photon emission computed tomography, combined with computed tomography (SPECT/CT) is one of those methods. Its role in nuclear cardiology is important, because it provides quick attenuation correction and calculates the calcium score. In nuclear endocrinology SPECT/CT participates in thyroid and parathyroid examinations, especially in cases, where there is a need for localization of ectopic parathyroid or thyroid tissue. In nuclear pulmonology, one of the best ways to attribute certain changes seen on the SPECT, to the zone of interest on the CT, is to study the fused images obtained from the SPECT/ CT scanner. In cases of suspected infection and inflammation, fused images are indispensable for accurate localization of the involved tissue (structure) and for discrimination between normal/abnormal uptake. Careful reading of the CT component (even low-dose) is related (in 10% of cases) to clinically important incidental findings: effusions, tumors, metastases or lymph node pathology. SPECT/CT increases the specificity of the examinations and improves significantly the localization of pathological processes. It provides additional information, shortens the diagnostic algorithm and influences the extent of surgical procedures. In many hybrid examinations the preferred CT component is a low-dose one, without considerable radiation exposure. The opportunity to combine nuclear medicine techniques and contrast CT images, aiming at better diagnosis needs further development. SPECT/CT provides important additional information and more accurate diagnostics in patients with benign diseases. (authors) Key words: SPECT/CT. BENIGN DISEASES

Myocardial Infarction Area Quantification using High-Resolution SPECT Images in Rats

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Oliveira, Luciano Fonseca Lemos de [Divisão de Cardiologia, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Mejia, Jorge [Faculdade de Medicina de São José do Rio Preto, São José do Rio Preto, SP (Brazil); Carvalho, Eduardo Elias Vieira de; Lataro, Renata Maria; Frassetto, Sarita Nasbine [Divisão de Cardiologia, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Fazan, Rubens Jr.; Salgado, Hélio Cesar [Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Galvis-Alonso, Orfa Yineth [Faculdade de Medicina de São José do Rio Preto, São José do Rio Preto, SP (Brazil); Simões, Marcus Vinícius, E-mail: msimoes@fmrp.usp.br [Divisão de Cardiologia, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)

2013-07-15

Imaging techniques enable in vivo sequential assessment of the morphology and function of animal organs in experimental models. We developed a device for high-resolution single photon emission computed tomography (SPECT) imaging based on an adapted pinhole collimator. To determine the accuracy of this system for quantification of myocardial infarct area in rats. Thirteen male Wistar rats (250 g) underwent experimental myocardial infarction by occlusion of the left coronary artery. After 4 weeks, SPECT images were acquired 1.5 hours after intravenous injection of 555 MBq of 99mTc-Sestamibi. The tomographic reconstruction was performed by using specially developed software based on the Maximum Likelihood algorithm. The analysis of the data included the correlation between the area of perfusion defects detected by scintigraphy and extent of myocardial fibrosis assessed by histology. The images showed a high target organ/background ratio with adequate visualization of the left ventricular walls and cavity. All animals presenting infarction areas were correctly identified by the perfusion images. There was no difference of the infarct area as measured by SPECT (21.1 ± 21.2%) and by histology (21.7 ± 22.0%; p=0.45). There was a strong correlation between individual values of the area of infarction measured by these two methods. The developed system presented adequate spatial resolution and high accuracy for the detection and quantification of myocardial infarction areas, consisting in a low cost and versatile option for high-resolution SPECT imaging of small rodents.

SPECT/CT imaging in bone scintigraphy of a case of clavicular osteoma

International Nuclear Information System (INIS)

Yamamoto, Yuka; Nishiyama, Yoshihiro

2014-01-01

Osteoma is a benign bone-forming tumor that usually arises in the craniofacial bones and rarely in the long bones. Clavicular involvement is extremely rare. We report a 51-year-old woman with osteoma of the left clavicle. Radiograph of the left shoulder showed a well-defined lobulated blastic mass in the proximal and mid-portion of the left clavicle. Bone scintigraphy was performed 4 hours after an intravenous injection of Tc-99m hydroxymethylene diphosphonate (HMDP). Whole-body image showed a focus of intensely increased uptake in the clavicle. Single photon emission computed tomography / computed tomography (SPECT/CT) images were also acquired and clearly showed intense uptake at the tumor site. Integrated SPECT/CT imaging supplies both functional and anatomic information about bone the SPECT imaging improves sensitivity compared with planar imaging, the CT imaging provides precise localization of the abnormal uptake, and information on the shape and structure of the abnormalities improves the specificity of the diagnosis

Intravenous dipyridamole thallium-201 SPECT imaging in patients with left bundle branch block

International Nuclear Information System (INIS)

Rockett, J.F.; Wood, W.C.; Moinuddin, M.; Loveless, V.; Parrish, B.

1990-01-01

Tl-201 exercise imaging in patients with left bundle branch block (LBBB) has proven to be indeterminate for significant left anterior descending (LAD) coronary artery stenosis because of the presence of immediate septal perfusion defects with redistribution on delayed images in almost all cases. Tl-201 redistribution occurs regardless of the presence or absence of LAD stenosis. Nineteen patients having LBBB were evaluated with dipyridamole Tl-201 SPECT. Fourteen of these subjects had normal dipyridamole Tl-201 SPECT imaging. Three patients had normal coronary angiograms. None of the remaining 11 patients with normal dipyridamole Tl-201 SPECT images was found to have clinical coronary artery disease in a 5-11 month follow-up period. Five patients had abnormal septal perfusion. Four underwent coronary angiography. One had a significant LAD stenosis. The single patient with septal redistribution who refused to undergo coronary angiography died shortly thereafter of clinical coronary artery disease. This preliminary work suggests that dipyridamole Tl-201 SPECT may be more useful for excluding LAD stenosis in patients with LBBB than Tl-201 exercise imaging

Performance characterization of the Inveon preclinical small-animal PET/SPECT/CT system for multimodality imaging

International Nuclear Information System (INIS)

Magota, Keiichi; Kubo, Naoki; Kuge, Yuji; Nishijima, Ken-ichi; Zhao, Songji; Tamaki, Nagara

2011-01-01

We investigated the performance of the Inveon small-animal PET/SPECT/CT system and compared the imaging capabilities of the SPECT and PET components. For SPECT, the energy resolution, tomographic spatial resolution and system sensitivity were evaluated with a 99m Tc solution using a single pinhole collimator. For PET, the spatial resolution, absolute sensitivity, scatter fraction and peak noise equivalent count were evaluated. Phantoms and a normal rat were scanned to compare the imaging capabilities of SPECT and PET. The SPECT spatial resolution was 0.84 mm full-width at half-maximum (FWHM) at a radius of rotation of 25 mm using a 0.5-mm pinhole aperture collimator, while the PET spatial resolution was 1.63 mm FWHM at the centre. The SPECT system sensitivity at a radius of rotation of 25 mm was 35.3 cps/MBq (4 x 10 -3 %) using the 0.5-mm pinhole aperture, while the PET absolute sensitivity was 3.2% for 350-650 keV and 3.432 ns. Accordingly, the volume sensitivity of PET was three orders of magnitude higher than that of SPECT. This integrated PET/SPECT/CT system showed high performance with excellent spatial resolution for SPECT and sensitivity for PET. Based on the tracer availability and system performance, SPECT and PET have complementary roles in multimodality small-animal imaging. (orig.)

Diagnosis of Alzheimer's disease using brain perfusion SPECT and MR imaging: which modality achieves better diagnostic accuracy?

International Nuclear Information System (INIS)

Kubota, Takao; Ushijima, Yo; Yamada, Kei; Okuyama, Chio; Kizu, Osamu; Nishimura, Tsunehiko

2005-01-01

The purpose of this study was to compare the accuracy of MR imaging and brain perfusion single-photon emission tomography (SPECT) in diagnosing Alzheimer's disease (AD). The transaxial section display of brain perfusion SPECT, three-dimensional stereotactic surface projection (3D-SSP) SPECT image sets, thin-section MR imaging of the hippocampus and perfusion MR imaging were evaluated in 66 subjects comprising 35 AD patients and 31 subjects without AD. SPECT and MR imaging were visually interpreted by two experts and two novices, and the diagnostic ability of each modality was evaluated by receiver operating characteristic (ROC) analysis. In the experts' interpretations, there was no significant difference in the area under the ROC curve (A z ) between 3D-SSP and thin-section MR imaging, whereas the A z of transaxial SPECT display was significantly lower than that of 3D-SSP (3D-SSP: 0.97, thin-section MR imaging: 0.96, transaxial SPECT: 0.91), and the A z of perfusion MR imaging was lowest (0.63). The sensitivity and specificity of each modality were, respectively, 80.0% and 96.8% for 3D-SSP, 77.1% and 96.8% for thin-section MR imaging, 60.0% and 93.5% for transaxial SPECT display and 34.3% and 100% for perfusion MR imaging. In the novices' interpretations, the A z , sensitivity and specificity of 3D-SSP were superior to those of thin-section MR imaging. Thin-section hippocampal MR imaging and 3D-SSP image sets had potentially equivalent value for the diagnosis of AD, and they were superior to transaxial SPECT display and perfusion MR imaging. For avoidance of the effect of interpreters' experience on image evaluation, 3D-SSP appears to be optimal. (orig.)

Quantitative evaluation of right ventricular overload in cor pulmonale using sup 201 Tl myocardial SPECT

Energy Technology Data Exchange (ETDEWEB)

Kato, Hiroshi; Misawa, Toshihiro; Kutsumi, Yasunori [Fukui Medical School, Matsuoka (Japan); and others

1991-01-01

To determine quantitatively the discriminant and characteristics of cor pulmonale, {sup 201}Tl myocardial perfusion SPECT was performed in 16 patients with chronic obstructive pulmonary disease (COPD) and 7 with restrictive pulmonary disease (RPD). One section of the short-axis SPECT image in which the right ventricle was most clearly visualized was selected. Tl-score was defined as the ratio of the sum of counts in the region of interest (ROI) at the anterior, mid, and posterior regions of the right ventricular free wall to the sum of counts in ROI at the posterior, lateral, and anterior walls of the left ventricle, and the anterior and posterior regions of the interventricular septum. In the group of COPD patients, Tl-score was positively correlated with mean pulmonary arterial pressure (mPAP), total pulmonary vascular resistance (TPR), and arterial carbon dioxide tension (PaCO{sub 2}), while it was inversely correlated with arterial oxygen tension (PaO{sub 2}). However, there was no significant correlation between Tl-score and mPAP, TPR, PaCO{sub 2}, and PaO{sub 2} in the group of RPD patients. In assessing pulmonary hypertension as defined by mPAP over 20 mmHg, a Tl-score greater than 0.25 was useful with a sensitivity of 69% and a specificity of 90%. The occurrence of cor pulmonale is a major factor in determining the prognosis of COPD patients. It was concluded that {sup 201}Tl myocardial SPECT is useful for evaluating right ventricular overload quantitatively, as well as for assessing core pulmonale, especially in COPD patients, since the ratio of Tl counts in the right and left ventricles was significantly correlated with right cardiopulmonary hemodynamic parameters. (N.K.).

Measurement of heterogeneous distribution on technegas SPECT images by three-dimensional fractal analysis

International Nuclear Information System (INIS)

Nagao, Michinobu; Murase, Kenya

2002-01-01

This review article describes a method for quantifying heterogeneous distribution on Technegas ( 99m Tc-carbon particle radioaerosol) SPECT images by three-dimensional fractal analysis (3D-FA). Technegas SPECT was performed to quantify the severity of pulmonary emphysema. We delineated the SPECT images by using five cut-offs (15, 20, 25, 30 and 35% of the maximal voxel radioactivity), and measured the total number of voxels in the areas surrounded by the contours obtained with each cut-off level. We calculated fractal dimensions from the relationship between the total number of voxels and the cut-off levels transformed into natural logarithms. The fractal dimension derived from 3D-FA is the relative and objective measurement, which can assess the heterogeneous distribution on Technegas SPECT images. The fractal dimension strongly correlate pulmonary function in patients with emphysema and well documented the overall and regional severity of emphysema. (author)

Episodic aphasia associated with tumor active multiple sclerosis: a correlative SPECT study utilising image fusion

International Nuclear Information System (INIS)

Roff, G.; Campbell, A.; Lawn, N.; Henderson, A.; McCarthy, M.; Lenzo, N.

2003-01-01

Full text: Cerebral perfusion imaging is a common technique to assess cerebral perfusion and metabolism. It can complement anatomical imaging in assessing a number of neurological conditions. At times it can better define the clinical manifestations of a disease process than anatomical imaging alone. We present a clinical case whereby cerebral SPECT imaging helped define the physiological reason for intermittent aphasia in a patient with tumor active multiple sclerotic white matter plaques. Cerebral SPECT studies were performed during a period of aphasia and when the patient had recovered. We utilised subtraction analyses and image fusion techniques to better define the changes seen on SPECT. We discuss the neuroanatomical relationship of aphasia and the automatic fusion technique that allows accurate co-registration of the MRI and SPECT data. Copyright (2003) The Australian and New Zealand Society of Nuclear Medicine Inc

PET/SPECT/CT multimodal imaging in a transgenic mouse model of breast cancer

Energy Technology Data Exchange (ETDEWEB)

Boisgard, R.; Alberini, J.L.; Jego, B.; Siquier, K.; Theze, B.; Guillermet, S.; Tavitian, B. [Service Hospitalier Frederic Joliot, Institut d' Imagerie BioMedicale, CEA, 91 - Orsay (France); Inserm, U803, 91 - Orsay (France)

2008-02-15

Background. - In the therapy monitoring of breast cancer, conventional imaging methods include ultrasound, mammography, CT and MRI, which are essentially based on tumor size modifications. However these modifications represent a late consequence of the biological response and fail to differentiate scar or necrotic tissue from residual viable tumoral tissue. Therefore, a current objective is to develop tools able to predict early response to treatment. Positron Emission Tomography (PET) and Single Photon Emission Computerized Tomography (SPECT) are imaging modalities able to provide extremely sensitive quantitative molecular data and are widely used in humans and animals. Results. - Mammary epithelial cells of female transgenic mice expressing the polyoma middle T onco-protein (Py M.T.), undergo four distinct stages of tumour progression, from pre malignant to malignant stages. Stages are identifiable in the mammary tissue and can lead to the development of distant metastases Longitudinal studies by dynamic whole body acquisitions by multimodal imaging including PET, SPECT and Computed Tomography (CT) allow following the tumoral evolution in Py M.T. mice in comparison with the histopathological analysis. At four weeks of age, mammary hyperplasia was identified by histopathology, but no abnormalities were found by palpation or detected by PET with 2-deoxy-2-[{sup 18}F]fluoro-D-glucose. Such as in some human mammary cancers, the sodium iodide sym-porter (N.I.S.) in tumoral mammary epithelial cells is expressed in this mouse model. In order to investigate the expression of N.I.S. in the Py M.T. mice mammary tumours, [{sup 99m}Tc]TcO{sub 4} imaging was performed with a dedicated SPECT/CT system camera (B.I.O.S.P.A.C.E. Gamma Imager/CT). Local uptake of [{sup 99m}Tc]TcO{sub 4} was detected as early as four weeks of age. The efficacy of chemotherapy was evaluated in this mouse model using a conventional regimen (Doxorubicine, 100 mg/ kg) administered weekly from nine to

Ejection fraction in myocardial perfusion imaging assessed with a dynamic phantom: comparison between IQ-SPECT and LEHR.

Science.gov (United States)

Hippeläinen, Eero; Mäkelä, Teemu; Kaasalainen, Touko; Kaleva, Erna

2017-12-01

Developments in single photon emission tomography instrumentation and reconstruction methods present a potential for decreasing acquisition times. One of such recent options for myocardial perfusion imaging (MPI) is IQ-SPECT. This study was motivated by the inconsistency in the reported ejection fraction (EF) and left ventricular (LV) volume results between IQ-SPECT and more conventional low-energy high-resolution (LEHR) collimation protocols. IQ-SPECT and LEHR quantitative results were compared while the equivalent number of iterations (EI) was varied. The end-diastolic (EDV) and end-systolic volumes (ESV) and the derived EF values were investigated. A dynamic heart phantom was used to produce repeatable ESVs, EDVs and EFs. Phantom performance was verified by comparing the set EF values to those measured from a gated multi-slice X-ray computed tomography (CT) scan (EF True ). The phantom with an EF setting of 45, 55, 65 and 70% was imaged with both IQ-SPECT and LEHR protocols. The data were reconstructed with different EI, and two commonly used clinical myocardium delineation software were used to evaluate the LV volumes. The CT verification showed that the phantom EF settings were repeatable and accurate with the EF True being within 1% point from the manufacture's nominal value. Depending on EI both MPI protocols can be made to produce correct EF estimates, but IQ-SPECT protocol produced on average 41 and 42% smaller EDV and ESV when compared to the phantom's volumes, while LEHR protocol underestimated volumes by 24 and 21%, respectively. The volume results were largely similar between the delineation methods used. The reconstruction parameters can greatly affect the volume estimates obtained from perfusion studies. IQ-SPECT produces systematically smaller LV volumes than the conventional LEHR MPI protocol. The volume estimates are also software dependent.

Baseline and cognition activated brain SPECT imaging in depression

International Nuclear Information System (INIS)

Zhao Jinhua; Lin Xiangtong; Jiang Kaida; Liu Yongchang; Xu Lianqin

1998-01-01

Purpose: To evaluate the regional cerebral blood flow (rCBF) abnormalities through the semiquantitative analysis of the baseline and cognition activated rCBF imaging in unmedicated depressed patients. Methods: 27 depressed patients unmedicated by anti-depressants were enrolled. The diagnosis (depression of moderate degree with somatization) was confirmed by the ICD-10 criteria. 15 age matched normal controls were studied under identical conditions. Baseline and cognition activated 99m Tc-ECD SPECT were performed on 21 of the 27 patients with depression and 13 of the 15 normal controls. Baseline 99m Tc-ECD SPECT alone were performed on the rest 6 patients with depression and 2 normal controls. The cognitive activation is achieved by Wisconsin Card Sorting Test (WCST). 1110 MBq of 99m Tc-ECD was administered by intravenous bolus injection 5 minutes after the onset of the WCST. Semi-quantitative analysis was conducted with the 7th, 8th, 9th, 10th, 11th slices of the transaxial imaging. rCBF ratios of every ROI were calculated using the average tissue activity in the region divided by the maximum activity in the cerebellum. Results: 1) The baseline rCBF of left frontal (0.720) and left temporal lobe (0.720) were decreased significantly in depressed patients comparing with those of the control subjects. 2) The activated rCBF of left frontal lobe (0.719) and left temporal lobe (0.690), left parietal lobe (0.701) were decreased evidently than those of the controls. Conclusions: 1) Hypoperfusions of left frontal and left temporal cortexes were identified in patients with depression. 2) The hypoperfusion of left frontal and left temporal cortexes may be the cause of cognition disorder and depressed mood in patients with depression. 3) Cognition activated brain perfusion imaging is helpful for making a more accurate diagnosis of depression

A hardware investigation of robotic SPECT for functional and molecular imaging onboard radiation therapy systems

International Nuclear Information System (INIS)

Yan, Susu; Tough, MengHeng; Bowsher, James; Yin, Fang-Fang; Cheng, Lin

2014-01-01

Purpose: To construct a robotic SPECT system and to demonstrate its capability to image a thorax phantom on a radiation therapy flat-top couch, as a step toward onboard functional and molecular imaging in radiation therapy. Methods: A robotic SPECT imaging system was constructed utilizing a gamma camera detector (Digirad 2020tc) and a robot (KUKA KR150 L110 robot). An imaging study was performed with a phantom (PET CT Phantom TM ), which includes five spheres of 10, 13, 17, 22, and 28 mm diameters. The phantom was placed on a flat-top couch. SPECT projections were acquired either with a parallel-hole collimator or a single-pinhole collimator, both without background in the phantom and with background at 1/10th the sphere activity concentration. The imaging trajectories of parallel-hole and pinhole collimated detectors spanned 180° and 228°, respectively. The pinhole detector viewed an off-centered spherical common volume which encompassed the 28 and 22 mm spheres. The common volume for parallel-hole system was centered at the phantom which encompassed all five spheres in the phantom. The maneuverability of the robotic system was tested by navigating the detector to trace the phantom and flat-top table while avoiding collision and maintaining the closest possible proximity to the common volume. The robot base and tool coordinates were used for image reconstruction. Results: The robotic SPECT system was able to maneuver parallel-hole and pinhole collimated SPECT detectors in close proximity to the phantom, minimizing impact of the flat-top couch on detector radius of rotation. Without background, all five spheres were visible in the reconstructed parallel-hole image, while four spheres, all except the smallest one, were visible in the reconstructed pinhole image. With background, three spheres of 17, 22, and 28 mm diameters were readily observed with the parallel-hole imaging, and the targeted spheres (22 and 28 mm diameters) were readily observed in the pinhole

Extraosseous accumulation of bone scanning agents in malignant brain tumors. Comparison to semi-quantitative evaluation with 99mTc SPECT/201Tl SPECT and histological findings

International Nuclear Information System (INIS)

Suzuki, Aya

2003-01-01

Although 201 Tl chloride (Tl) SPECT has been used in the differential diagnosis between recurrence of malignant brain tumor and necrosis after treatment, it is not generally recognized as a definite modality to distinguish them. We conducted a preliminary study using Tl SPECT and 99m Tc-MDP or 99m Tc-HMDP (Tc) SPECT because it has been said that extraosseous accumulation was caused by calcium deposits in necrotic tissues. In our study, for the purposes of clarifying the mechanism of extraosseous uptake and the correlation between extraosseous accumulation of bone-scanning agent and tumor viability in malignant brain tumors, we compared whether Tc uptake was correlated with the histopathological findings and further performed semi-quantitative evaluation between Tc SPECT and Tl SPECT. The correlation coefficients between the ratio of tumor to normal skull count obtained from Tc SPECT (Tc-T/N) and those of tumor to normal brain count (T/N) and to normal scalp count (T/S) both obtained from Tl SPECT were calculated. Using contrast enhanced CT (CE-CT) or contrast enhanced MRI (CE-MRI), 8 of 10 cases showed intensely ring-enhanced tumor with necrotic lesion. Histopathologically, 7 of 8 cases whose tumor had been resected before treatment had necrosis with increased vascularity or bleeding. Of the remaining 2 cases one case, malignant lymphoma had only hypervascularity by biopsy, while the other one was excluded for resection after treatment. Three of these 8 cases whose CE-CT or CE-MRI showed necrotic lesions exhibited Tc and Tl accumulations in the area corresponding to necrosis. In contrast, 2 showed no Tc nor Tl uptake. Tc-T/N had no significant correlation with any of early-, delayed-T/N or T/S. In conclusion, there was no significant correlation between Tc and Tl uptakes by malignant brain tumors in semi-quantitative evaluation. (author)

SPECT and PET Serve as Molecular Imaging Techniques and in Vivo Biomarkers for Brain Metastases

Science.gov (United States)

Palumbo, Barbara; Buresta, Tommaso; Nuvoli, Susanna; Spanu, Angela; Schillaci, Orazio; Fravolini, Mario Luca; Palumbo, Isabella

2014-01-01

Nuclear medicine techniques (single photon emission computerized tomography, SPECT, and positron emission tomography, PET) represent molecular imaging tools, able to provide in vivo biomarkers of different diseases. To investigate brain tumours and metastases many different radiopharmaceuticals imaged by SPECT and PET can be used. In this review the main and most promising radiopharmaceuticals available to detect brain metastases are reported. Furthermore the diagnostic contribution of the combination of SPECT and PET data with radiological findings (magnetic resonance imaging, MRI) is discussed. PMID:24897023

Examination of attenuation correction method for cerebral blood Flow SPECT Using MR imaging

International Nuclear Information System (INIS)

Mizuno, Takashi; Takahashi, Masaaki

2009-01-01

Authors developed a software for attenuation correction using MR imaging (MRAC) (Toshiba Med. System Engineer.) based on the idea that precision of AC could be improved by the head contour in MRI T2-weighted images (T2WI) obtained before 123 I-iofetamine (IMP) single photon emission computed tomography (SPECT) for cerebral blood flow (CBF) measurement. In the present study, this MRAC was retrospectively evaluated by comparison with the previous standard AC methods derived from transmission CT (TCT) and X-CT which overcoming the problem of sinogram threshold Chang method but still having cost and patient exposure issues. MRAC was essentially performed in the Toshiba GMS5500/PI processor where 3D registration was conducted with images of SPECT and MRI of the same patient. The gamma camera for 123 I-IMP SPECT and 99m TcO 4 - TCT was Toshiba 3-detector GCA9300A equipped with the above processor for MRAC and with low energy high resolution (LEHR) fan beam collimator. Machines for MRI and CT were Siemens-Asahi Meditech. MAGNETOM Symphony 1.5T and SOMATOM plus4, respectively. MRAC was examined in 8 patients with images of T1WI, TCT and SPECT, and in 18 of T2WI, CT and SPECT. Evaluation was made by comparison of attenuation coefficients (μ) by the 4 methods. As a result, the present MRAC was found to be closer to AC by TCT and CT than by the Chang method since MRAC, due to exact imaging of the head contour, was independent on radiation count, and was thought to be useful for improving the precision of CBF SPECT. (K.T.)

Myocardial CT perfusion imaging and SPECT for the diagnosis of coronary artery disease

DEFF Research Database (Denmark)

George, Richard T; Mehra, Vishal C; Chen, Marcus Y

2014-01-01

%, respectively, for SPECT. CONCLUSION: The overall performance of myocardial CT perfusion imaging in the diagnosis of anatomic CAD (stenosis ≥50%), as demonstrated with the Az, was higher than that of SPECT and was driven in part by the higher sensitivity for left main and multivessel disease.......PURPOSE: To compare the diagnostic performance of myocardial computed tomographic (CT) perfusion imaging and single photon emission computed tomography (SPECT) perfusion imaging in the diagnosis of anatomically significant coronary artery disease (CAD) as depicted at invasive coronary angiography....... MATERIALS AND METHODS: This study was approved by the institutional review board. Written informed consent was obtained from all patients. Sixteen centers enrolled 381 patients from November 2009 to July 2011. Patients underwent rest and adenosine stress CT perfusion imaging and rest and either exercise...

Nontraumatic femoral head necrosis. Classification of bone scintigraphic findings and diagnostic value of SPECT following planar imaging

Energy Technology Data Exchange (ETDEWEB)

Minoshima, Satoshi; Uchida, Yoshitaka; Anzai, Yoshimi; Uno, Kimiichi; Arimizu, Noboru [Chiba Univ. (Japan). School of Medicine

1994-09-01

This study was conducted to determine bone scintigraphic findings in nontraumatic femoral head avascular necrosis and diagnostic value of SPECT imaging following a conventional planar imaging. Forty-three femoral heads in twenty-six cases with idiopathic femoral head necrosis (n=2), systemic lupus erythematosus (n=22), aplastic anemia (n=1), and renal transplantation (n=1) were studied. The diagnosis for femoral head necrosis was based on magnetic resonance imaging as well as other diagnostic studies in all cases. Scintigraphic findings of planar and SPECT images were classified into six categories: normal (N); cold or decrease (C); partial increase with cold or decrease (PH+C); ring-like increase with a cold center (RH+C); partial increase (PH); diffuse and/or irregular increase (DH). Avascular necrosis was confirmed in twenty-four femoral heads, in which planar and SPECT images showed scintigraphic findings of N (n=3, 2), C (n=1, 3), PH+C (n=2, 8), RH+C (n=2, 3), PH (n=9, 2), and DH (n=7, 6), respectively. Femoral heads without avascular necrosis demonstrated planar and SPECT findings of N (n=16, 12), C (n=0, 6), and DH (n=3, 1), respectively. When considering C, PH+C, and RH+C as diagnostic findings for avascular necrosis, sensitivities of planar and SPECT images were 21% and 58%, and specificities were 100% and 68%, respectively. In nineteen femoral heads with normal planar findings (N), SPECT correctly identified avascular necrosis in two femoral heads and misidentified six normal femoral heads as avascular necrosis. In nineteen femoral heads with nondiagnostic abnormalities (PH, DH), SPECT correctly identified avascular necrosis in seven femoral heads and showed no false positive. Diagnostic planar findings in five femoral heads were concordant with SPECT diagnosis. These results indicate that SPECT imaging is most valuable when planar images show nondiagnostic abnormalities based on the proposed classification of scintigraphic findings. (author).

Nontraumatic femoral head necrosis. Classification of bone scintigraphic findings and diagnostic value of SPECT following planar imaging

International Nuclear Information System (INIS)

Minoshima, Satoshi; Uchida, Yoshitaka; Anzai, Yoshimi; Uno, Kimiichi; Arimizu, Noboru

1994-01-01

This study was conducted to determine bone scintigraphic findings in nontraumatic femoral head avascular necrosis and diagnostic value of SPECT imaging following a conventional planar imaging. Forty-three femoral heads in twenty-six cases with idiopathic femoral head necrosis (n=2), systemic lupus erythematosus (n=22), aplastic anemia (n=1), and renal transplantation (n=1) were studied. The diagnosis for femoral head necrosis was based on magnetic resonance imaging as well as other diagnostic studies in all cases. Scintigraphic findings of planar and SPECT images were classified into six categories: normal (N); cold or decrease (C); partial increase with cold or decrease (PH+C); ring-like increase with a cold center (RH+C); partial increase (PH); diffuse and/or irregular increase (DH). Avascular necrosis was confirmed in twenty-four femoral heads, in which planar and SPECT images showed scintigraphic findings of N (n=3, 2), C (n=1, 3), PH+C (n=2, 8), RH+C (n=2, 3), PH (n=9, 2), and DH (n=7, 6), respectively. Femoral heads without avascular necrosis demonstrated planar and SPECT findings of N (n=16, 12), C (n=0, 6), and DH (n=3, 1), respectively. When considering C, PH+C, and RH+C as diagnostic findings for avascular necrosis, sensitivities of planar and SPECT images were 21% and 58%, and specificities were 100% and 68%, respectively. In nineteen femoral heads with normal planar findings (N), SPECT correctly identified avascular necrosis in two femoral heads and misidentified six normal femoral heads as avascular necrosis. In nineteen femoral heads with nondiagnostic abnormalities (PH, DH), SPECT correctly identified avascular necrosis in seven femoral heads and showed no false positive. Diagnostic planar findings in five femoral heads were concordant with SPECT diagnosis. These results indicate that SPECT imaging is most valuable when planar images show nondiagnostic abnormalities based on the proposed classification of scintigraphic findings. (author)

Compensation for nonuniform attenuation in SPECT brain imaging

International Nuclear Information System (INIS)

Glick, S.J.; King, M.A.; Pan, T.S.; Soares, E.J.

1996-01-01

Accurate compensation for photon attenuation is needed to perform quantitative brain single-photon-emission computed tomographic (SPECT) imaging. Bellini's attenuation-compensation method has been used with a nonuniform attenuation map to account for the nonuniform attenuation properties of the head. Simulation studies using a three-dimensional (3-D) digitized anthropomorphic brain phantom were conducted to compare quantitative accuracy of reconstructions obtained with the nonuniform Bellini method to that obtained with the Chang method and to iterative reconstruction using maximum-likelihood expectation maximization (ML-EM). Using the Chang method and assuming the head to be a uniform attenuator gave reconstructions with an average bias of approximately 6-8%, whereas using the Bellini or the iterative ML-EM method with a nonuniform attenuation map gave an average bias of approximately 1%. The computation time required to implement nonuniform attenuation compensation with the Bellini algorithm is approximately equivalent to the time required to perform one iteration of ML-EM. Thus, using the Bellini method with a nonuniform attenuation map provides accurate compensation for photon attenuation within the head, and the method can be implemented in computation times suitable for routine clinical use

SPECT and PET Serve as Molecular Imaging Techniques and in Vivo Biomarkers for Brain Metastases

Directory of Open Access Journals (Sweden)

Barbara Palumbo

2014-06-01

Full Text Available Nuclear medicine techniques (single photon emission computerized tomography, SPECT, and positron emission tomography, PET represent molecular imaging tools, able to provide in vivo biomarkers of different diseases. To investigate brain tumours and metastases many different radiopharmaceuticals imaged by SPECT and PET can be used. In this review the main and most promising radiopharmaceuticals available to detect brain metastases are reported. Furthermore the diagnostic contribution of the combination of SPECT and PET data with radiological findings (magnetic resonance imaging, MRI is discussed.

Precise fusion of MRI and dual energy 111In WBC/99mTc HDP SPECT/CT in the diabetic foot using companion CT: an example of SPECT/MRI imaging

International Nuclear Information System (INIS)

Knešaurek, K.; Heiba, S.; Kolker, D.; Vatti, S.

2015-01-01

The purpose of our study was to correctly fuse MRI and SPECT 111 In WBC and 99m Tc HDP images using companion CT images. The fused images could be used to assess proper surgical approach in treatment of the diabetic foot. Nine patients who had dual energy 111 In WBC/ 99 m Tc HDP SPECT/CT and MRI studies within a week were investigated in an ongoing project. A GE Infinia SPECT/CT camera and Siemens MAGNETOM 1.5T MR system were used in this study. First, the MRI and corresponding CT images were coregistrated using a transformation based on normalized mutual information. The transformation was saved and used for MRI and 111 In WBC/ 99 m Tc HDP SPECT fusion. A Jaszczak phantom study was also performed in order to estimate accuracy of MRI/ SPECT fusion. The Jaszczak phantom study with 3.7 MBq 111 In hot sphere showed that MRI/SPECT alignment using the approach described above produced registration with 0.7±0.4 mm accuracy in all three dimensions (3D). The nine clinical cases were visually evaluated and showed 1-2 mm 3D fusion accuracy. MRI provides almost perfect anatomy of soft tissue and bony structures but it may exaggerate the extent of infection. 111 In WBC/ 99 m Tc HDP SPECT imaging is more accurate for infection detection but lacks anatomical reference. Combination of these images proved an essential adjunct to diagnosis. A clinical utility of the approach is illustrated in two clinical examples. In conclusion, the CT in dual energy 111 In WBC/ 99 m Tc HDP SPECT/CT studies can be used to accurately fuse and compare 111 In WBC/ 99 m Tc HDP SPECT and MRI images of the diabetic foot. This can significantly help in conservative treatment planning and limb salvage procedures in treatment of diabetic foot infections.

Preliminary application of brain perfusion SPECT imaging in schizophrenia

International Nuclear Information System (INIS)

Wu Zhixing; Guo Chanliu; Li Xingbao; Liang Rongxiang; Zhao Jun; Yan Tingxiu

1996-01-01

The clinical value of 99m Tc-ECD brain perfusion SPECT imaging was evaluated in patients with schizophrenia. 32 patients with schizophrenia and 21 normal controls were analyzed with 99m Tc-ECD SPECT. 93.8% (30/32) of the patients showed decreased regional cerebral blood flow (rCBF). There was normal rCBF in controls. In the patient group rCBF decreased significantly in bilateral frontal lobes, left temporal lobe and right basal ganglion. The rCBF of left temporal lobe was significantly lower than that of right temporal lobe. The decreasing rCBF was not significantly related to previous treatment and duration of illness. 99m Tc-ECD SPECT is useful for the study and diagnosis of patients with schizophrenia

Basic study for the purpose of developing a quantitative "6"7Ga-SPECT measurement method

International Nuclear Information System (INIS)

Nakanishi, Kensuke; Sakata, Reiki; Takaki, Akihiro; Ito, Shigeki; Nakasone, Yutaka; Kadota, Masataka

2017-01-01

"6"7Ga-single photon emission computed tomography (SPECT) images vary according to the imaging time and image display methods. The calculation of an index, such as the standardized uptake value used in positron emission tomography, from "6"7Ga-SPECT images would enable the accurate evaluation of the region of accumulation. The purpose of this study was to elucidate the conversion formula, the lower detection limit (LDL), and recovery coefficient (RC) for quantifying the radiation concentration in the "6"7Ga accumulation site. After chronologically obtaining SPECT/CT images at a radiation concentration of 1.0-442.4 kBq/mL with 27 bottles (diameter: 48 mm ,100 mL), the radiation concentration conversion formula was calculated using the successive approximation reconstruction method. The conversion coefficient was then calculated from the relationship between the count rate and the radiation concentration, and the LDL was determined. To compensate for the partial volume effect, the recovery curve was calculated using the mean SPECT count for six bottles (diameter: 9 ,18 , 29, 38, 48, and 94 mm). There was a linear relationship between the radiation concentration and the count rate with a good correlation (r=0.99). The LDL was 1.0 kBq/mL. The recovery curve reached a plateau at a diameter of at least 48 mm. The calculation of the absorbed dose index was possible using the radiation concentration conversion formula and the RC. (author)

Design and evaluation of a mobile bedside PET/SPECT imaging system

Science.gov (United States)

Studenski, Matthew Thomas

Patients confined to an intensive care unit, the emergency room, or a surgical suite are managed without nuclear medicine procedures such as positron emission tomography (PET) or single photon emission computed tomography (SPECT). These studies have diagnostic value which can greatly benefit the physician's treatment of the patient but require that the patient is moved to a scanner. This dissertation examines the feasibility of an economical PET/SPECT system that can be brought to the bedside of an immobile patient for imaging. We chose to focus on cardiac SPECT imaging including perfusion imaging using 99mTc tracers and viability imaging using 18F tracers first because of problems arising from positioning a detector beneath a patient's bed, a requirement for the opposed detector orientation in PET imaging. Second, SPECT imaging acquiring over the anterior 180 degrees of the patient results in reduced attenuation effects due to the heart's location in the anterior portion of the body. Four studies were done to assess the clinical feasibility of the mobile system; 1) the performance of the system was evaluated in SPECT mode at both 140 keV (99mTc tracers) and 511 keV (positron emitting tracers), 2) a dynamic cardiac phantom was used to develop and test image acquisition and processing methods for the system at both energies, 3) a high energy pinhole collimator was designed to reduce the effects of high energy photon penetration through the parallel hole collimator, and 4) we estimated the radiation dose to persons that would be in the vicinity of a patient to ensure that the effective dose is below the regulatory limit. With these studies, we show that the mobile system provides an economical means of bringing nuclear medicine to an immobile patient while staying below the regulatory dose limit to other persons. The system performed well at both 140 keV and 511 keV and provided viable images of a phantom myocardium at both energies. The system does not achieve the

Improved dose–volume histogram estimates for radiopharmaceutical therapy by optimizing quantitative SPECT reconstruction parameters

International Nuclear Information System (INIS)

Cheng Lishui; Hobbs, Robert F; Sgouros, George; Frey, Eric C; Segars, Paul W

2013-01-01

In radiopharmaceutical therapy, an understanding of the dose distribution in normal and target tissues is important for optimizing treatment. Three-dimensional (3D) dosimetry takes into account patient anatomy and the nonuniform uptake of radiopharmaceuticals in tissues. Dose–volume histograms (DVHs) provide a useful summary representation of the 3D dose distribution and have been widely used for external beam treatment planning. Reliable 3D dosimetry requires an accurate 3D radioactivity distribution as the input. However, activity distribution estimates from SPECT are corrupted by noise and partial volume effects (PVEs). In this work, we systematically investigated OS-EM based quantitative SPECT (QSPECT) image reconstruction in terms of its effect on DVHs estimates. A modified 3D NURBS-based Cardiac-Torso (NCAT) phantom that incorporated a non-uniform kidney model and clinically realistic organ activities and biokinetics was used. Projections were generated using a Monte Carlo (MC) simulation; noise effects were studied using 50 noise realizations with clinical count levels. Activity images were reconstructed using QSPECT with compensation for attenuation, scatter and collimator–detector response (CDR). Dose rate distributions were estimated by convolution of the activity image with a voxel S kernel. Cumulative DVHs were calculated from the phantom and QSPECT images and compared both qualitatively and quantitatively. We found that noise, PVEs, and ringing artifacts due to CDR compensation all degraded histogram estimates. Low-pass filtering and early termination of the iterative process were needed to reduce the effects of noise and ringing artifacts on DVHs, but resulted in increased degradations due to PVEs. Large objects with few features, such as the liver, had more accurate histogram estimates and required fewer iterations and more smoothing for optimal results. Smaller objects with fine details, such as the kidneys, required more iterations and less

Improved dose-volume histogram estimates for radiopharmaceutical therapy by optimizing quantitative SPECT reconstruction parameters

Science.gov (United States)

Cheng, Lishui; Hobbs, Robert F.; Segars, Paul W.; Sgouros, George; Frey, Eric C.

2013-06-01

In radiopharmaceutical therapy, an understanding of the dose distribution in normal and target tissues is important for optimizing treatment. Three-dimensional (3D) dosimetry takes into account patient anatomy and the nonuniform uptake of radiopharmaceuticals in tissues. Dose-volume histograms (DVHs) provide a useful summary representation of the 3D dose distribution and have been widely used for external beam treatment planning. Reliable 3D dosimetry requires an accurate 3D radioactivity distribution as the input. However, activity distribution estimates from SPECT are corrupted by noise and partial volume effects (PVEs). In this work, we systematically investigated OS-EM based quantitative SPECT (QSPECT) image reconstruction in terms of its effect on DVHs estimates. A modified 3D NURBS-based Cardiac-Torso (NCAT) phantom that incorporated a non-uniform kidney model and clinically realistic organ activities and biokinetics was used. Projections were generated using a Monte Carlo (MC) simulation; noise effects were studied using 50 noise realizations with clinical count levels. Activity images were reconstructed using QSPECT with compensation for attenuation, scatter and collimator-detector response (CDR). Dose rate distributions were estimated by convolution of the activity image with a voxel S kernel. Cumulative DVHs were calculated from the phantom and QSPECT images and compared both qualitatively and quantitatively. We found that noise, PVEs, and ringing artifacts due to CDR compensation all degraded histogram estimates. Low-pass filtering and early termination of the iterative process were needed to reduce the effects of noise and ringing artifacts on DVHs, but resulted in increased degradations due to PVEs. Large objects with few features, such as the liver, had more accurate histogram estimates and required fewer iterations and more smoothing for optimal results. Smaller objects with fine details, such as the kidneys, required more iterations and less

SPECT brain perfusion imaging in mild traumatic brain injury

International Nuclear Information System (INIS)

Li Juan; Liu Baojun; Zhao Feng; He Lirong; Xia Yucheng

2003-01-01

Objective: To study the clinical value of SPECT brain perfusion imaging after mild traumatic brain injury and to evaluate the mechanism of brain blood flow changes in the brain traumatic symptoms. Methods: SPECT 99 Tc m -ethylene cysteinate dimer (ECD) brain perfusion imaging was performed on 39 patients with normal consciousness and normal computed tomography. The study was performed on 23 patients within 3 months after the accidental injury and on 16 patients at more than 3 months post-injury. The cerebellum was used as the reference site (100% maximum value). Any decrease in cerebral perfusion in cortex or basal ganglia to below 70%, or even to below 50% in the medial temporal lobe, compared to the cerebellar reference was considered abnormal. Results: The results of 23 patients (59%) were abnormal. Among them, 20 patients showed 74 focal lesions with an average of 3.7 per patient (15 studies performed within 3 months and 8 studies performed more than 3 months after injury). The remaining 3 showed diffuse hypoperfusion (two at the early stage and one at more than 3 months after the injury). The 13 abnormal studies performed at the early stage showed 58 lesions (average, 4.5 per patient), whereas there was a reduction to an average of 2.3 per patient in the 7 patients (total 16 lesions) at more than 3 months post-injury. In the 20 patients with focal lesions, mainly the following regions were involved: frontal lobes 43.2% (32/74), basal ganglia 24.3% (18/74) and temporal lobes 17.6% (13/74). Conclusions: 1) SPECT brain perfusion imaging is more sensitive than computed tomography in detecting brain lesions of mild traumatic brain injury. 2) SPECT brain perfusion imaging is more sensitive at early stage than at late stage after injury. 3) The most common complaints were headache, dizziness, memory deficit. The patients without loss of consciousness may present brain hypoperfusion, too. 4) The changes may explain a neurological component of the patient symptoms in

Design and evaluation of corn starch-bonded Rhizophora spp. particleboard phantoms for SPECT/CT imaging

Science.gov (United States)

Hamid, Puteri Nor Khatijah Abd; Yusof, Mohd Fahmi Mohd; Aziz Tajuddin, Abd; Hashim, Rokiah; Zainon, Rafidah

2018-01-01

The aim of this study was to design and evaluate of corn starch-bonded Rhizophora spp. particleboards as phantom for SPECT/CT imaging. The phantom was designed according to the Jaszczak phantom commonly used in SPECT imaging with dimension of 22 cm diameter and 18 cm length. Six inserts with different diameter were made for insertion of vials filled with 1.6 µCi/ml of 99mTc unsealed source. The particleboard phantom was scanned using SPECT/CT imaging protocol. The contrast of each vial for particleboards phantom were calculated based on the ratio of counts in radionuclide volume and phantom background and compared to Perspex® and water phantom. The results showed that contrast values for each vial in particleboard phantomis near to 1.0 and in good agreement with Perspex® and water phantoms as common phantom materials for SPECT/CT. The paired sample t-test result showed no significant difference of contrast values between images in particleboard phantoms and that in water. The overall results showed the potential of corn starch-bonded Rhizophora spp. as phantom for quality control and dosimetry works in SPECT/CT imaging.

of Hypoxia-Inducible Factor-1α Activity by the Fusion of High-Resolution SPECT and Morphological Imaging Tests

Directory of Open Access Journals (Sweden)

Hirofumi Fujii

2012-01-01

Full Text Available Purpose. We aimed to clearly visualize heterogeneous distribution of hypoxia-inducible factor 1α (HIF activity in tumor tissues in vivo. Methods. We synthesized of 125I-IPOS, a 125I labeled chimeric protein probe, that would visualize HIF activity. The biodistribution of 125I-IPOS in FM3A tumor-bearing mice was evaluated. Then, the intratumoral localization of this probe was observed by autoradiography, and it was compared with histopathological findings. The distribution of 125I-IPOS in tumors was imaged by a small animal SPECT/CT scanner. The obtained in vivo SPECT-CT fusion images were compared with ex vivo images of excised tumors. Fusion imaging with MRI was also examined. Results. 125I-IPOS well accumulated in FM3A tumors. The intratumoral distribution of 125I-IPOS by autoradiography was quite heterogeneous, and it partially overlapped with that of pimonidazole. High-resolution SPECT-CT fusion images successfully demonstrated the heterogeneity of 125I-IPOS distribution inside tumors. SPECT-MRI fusion images could give more detailed information about the intratumoral distribution of 125I-IPOS. Conclusion. High-resolution SPECT images successfully demonstrated heterogeneous intratumoral distribution of 125I-IPOS. SPECT-CT fusion images, more favorably SPECT-MRI fusion images, would be useful to understand the features of heterogeneous intratumoral expression of HIF activity in vivo.

Geometric Calibration and Image Reconstruction for a Segmented Slant-Hole Stationary Cardiac SPECT System.

Science.gov (United States)

Mao, Yanfei; Yu, Zhicong; Zeng, Gengsheng L

2015-06-01

A dedicated stationary cardiac single-photon emission computed tomography (SPECT) system with a novel segmented slant-hole collimator has been developed. The goal of this paper is to calibrate this new imaging geometry with a point source. Unlike the commercially available dedicated cardiac SPECT systems, which are specialized and can be used only to image the heart, our proposed cardiac system is based on a conventional SPECT system but with a segmented slant-hole collimator replacing the collimator. For a dual-head SPECT system, 2 segmented collimators, each with 7 sections, are arranged in an L-shaped configuration such that they can produce a complete cardiac SPECT image with only one gantry position. A calibration method was developed to estimate the geometric parameters of each collimator section as well as the detector rotation radius, under the assumption that the point source location is calculated using the central-section data. With a point source located off the rotation axis, geometric parameters for each collimator section can be estimated independently. The parameters estimated individually are further improved by a joint objective function that uses all collimator sections simultaneously and incorporates the collimator symmetry information. Estimation results and images reconstructed from estimated parameters are presented for both simulated and real data acquired from a prototype collimator. The calibration accuracy was validated by computer simulations with an error of about 0.1° for the slant angles and about 1 mm for the rotation radius. Reconstructions of a heart-insert phantom did not show any image artifacts of inaccurate geometric parameters. Compared with the detector's intrinsic resolution, the estimation error is small and can be ignored. Therefore, the accuracy of the calibration is sufficient for cardiac SPECT imaging. © 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Optimization of Butterworth filter for brain SPECT imaging

International Nuclear Information System (INIS)

Minoshima, Satoshi; Maruno, Hirotaka; Yui, Nobuharu

1993-01-01

A method has been described to optimize the cutoff frequency of the Butterworth filter for brain SPECT imaging. Since a computer simulation study has demonstrated that separation between an object signal and the random noise in projection images in a spatial-frequency domain is influenced by the total number of counts, the cutoff frequency of the Butterworth filter should be optimized for individual subjects according to total counts in a study. To reveal the relationship between the optimal cutoff frequencies and total counts in brain SPECT study, we used a normal volunteer and 99m Tc hexamethyl-propyleneamine oxime (HMPAO) to obtain projection sets with different total counts. High quality images were created from a projection set with an acquisition time of 300-seconds per projection. The filter was optimized by calculating mean square errors from high quality images visually inspecting filtered reconstructed images. Dependence between total counts and optimal cutoff frequencies was clearly demonstrated in a nomogram. Using this nomogram, the optimal cutoff frequency for each study can be estimated from total counts, maximizing visual image quality. The results suggest that the cutoff frequency of Butterworth filter should be determined by referring to total counts in each study. (author)

Assessment of technetium-99m technegas scintigraphy for ventilatory impairment in pulmonary emphysema. Comparison of planar and SPECT images

International Nuclear Information System (INIS)

Satoh, Katashi; Tanabe, Masatada; Takahashi, Kazue

1997-01-01

Pulmonary emphysema can be diagnosed easily by X-ray CT (CT) as a low attenuation area. Recently Tc-99m-Technegas (Technegas) has been used for ventilation scintigraphy. The present study was undertaken to assess the usefulness of planar and SPECT images by using Technegas scintigraphy in patients with pulmonary emphysema. Technegas scintigraphy, CT and pulmonary function tests were performed in 20 patients (males, age 32-78 years). We classified the findings of Technegas images into 4 grades. Comparing planar and SPECT images of Technegas, more detailed findings were shown by SPECT than by planar images in mild cases (6 cases, 30%). In more severe cases, findings of SPECT and planar images were equivalent (14 cases, 70%). The degree of abnormal findings obtained by SPECT was equivalent to that obtained by CT in severe cases (6 cases, 30%). SPECT should be excluded in advanced stages as indicated by planar images. (author)

Small-animal SPECT and SPECT/CT: application in cardiovascular research

Energy Technology Data Exchange (ETDEWEB)

Golestani, Reza; Dierckx, Rudi A.J.O. [University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); Wu, Chao [University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); University Medical Center Utrecht, Image Sciences Institute and Rudolf Magnus Institute of Neurosciences, Utrecht (Netherlands); Tio, Rene A. [University Medical Center Groningen, Thorax Center, Department of Cardiology, Groningen (Netherlands); University Medical Center Groningen, Cardiovascular Imaging Group, P.O. Box 30001, Groningen (Netherlands); Zeebregts, Clark J. [University Medical Center Groningen, Department of Surgery, Division of Vascular Surgery, Groningen (Netherlands); University Medical Center Groningen, Cardiovascular Imaging Group, P.O. Box 30001, Groningen (Netherlands); Petrov, Artiom D. [University of California, Irvine, Division of Cardiology, School of Medicine, Irvine, California (United States); Beekman, Freek J. [University Medical Center Utrecht, Image Sciences Institute and Rudolf Magnus Institute of Neurosciences, Utrecht (Netherlands); Delft University of Technology, Faculty of Applied Sciences, Section Radiation Detection and Medical Imaging, Delft (Netherlands); MILabs, Utrecht (Netherlands); Boersma, Hendrikus H. [University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); University Medical Center Groningen, Department of Clinical and Hospital Pharmacy, Hanzeplein 1, P.O. Box 30001, Groningen (Netherlands); University Medical Center Groningen, Cardiovascular Imaging Group, P.O. Box 30001, Groningen (Netherlands); Slart, Riemer H.J.A. [University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); University Medical Center Groningen, Cardiovascular Imaging Group, P.O. Box 30001, Groningen (Netherlands)

2010-09-15

Preclinical cardiovascular research using noninvasive radionuclide and hybrid imaging systems has been extensively developed in recent years. Single photon emission computed tomography (SPECT) is based on the molecular tracer principle and is an established tool in noninvasive imaging. SPECT uses gamma cameras and collimators to form projection data that are used to estimate (dynamic) 3-D tracer distributions in vivo. Recent developments in multipinhole collimation and advanced image reconstruction have led to sub-millimetre and sub-half-millimetre resolution SPECT in rats and mice, respectively. In this article we review applications of microSPECT in cardiovascular research in which information about the function and pathology of the myocardium, vessels and neurons is obtained. We give examples on how diagnostic tracers, new therapeutic interventions, pre- and postcardiovascular event prognosis, and functional and pathophysiological heart conditions can be explored by microSPECT, using small-animal models of cardiovascular disease. (orig.)

Small-animal SPECT and SPECT/CT: application in cardiovascular research

International Nuclear Information System (INIS)

Golestani, Reza; Dierckx, Rudi A.J.O.; Wu, Chao; Tio, Rene A.; Zeebregts, Clark J.; Petrov, Artiom D.; Beekman, Freek J.; Boersma, Hendrikus H.; Slart, Riemer H.J.A.

2010-01-01

Preclinical cardiovascular research using noninvasive radionuclide and hybrid imaging systems has been extensively developed in recent years. Single photon emission computed tomography (SPECT) is based on the molecular tracer principle and is an established tool in noninvasive imaging. SPECT uses gamma cameras and collimators to form projection data that are used to estimate (dynamic) 3-D tracer distributions in vivo. Recent developments in multipinhole collimation and advanced image reconstruction have led to sub-millimetre and sub-half-millimetre resolution SPECT in rats and mice, respectively. In this article we review applications of microSPECT in cardiovascular research in which information about the function and pathology of the myocardium, vessels and neurons is obtained. We give examples on how diagnostic tracers, new therapeutic interventions, pre- and postcardiovascular event prognosis, and functional and pathophysiological heart conditions can be explored by microSPECT, using small-animal models of cardiovascular disease. (orig.)

Autoradiography study and SPECT imaging of reporter gene HSV1-tk expression in heart

Energy Technology Data Exchange (ETDEWEB)

Lan Xiaoli [Department of Nuclear Medicine, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Hubei Province Key Laboratory of Molecular Imaging, Wuhan, Hubei Province, 430022 (China)], E-mail: LXL730724@hotmail.com; Liu Ying; He Yong; Wu Tao; Zhang Binqing; Gao Zairong; An Rui [Department of Nuclear Medicine, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Hubei Province Key Laboratory of Molecular Imaging, Wuhan, Hubei Province, 430022 (China); Zhang Yongxue [Department of Nuclear Medicine, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Hubei Province Key Laboratory of Molecular Imaging, Wuhan, Hubei Province, 430022 (China)], E-mail: zhyx1229@163.com

2010-04-15

. The ARG images in region of interest-derived semi-quantitative study correlated well with ex vivo gamma counting and mRNA levels from RT-PCR analysis. The gamma counting and RT-PCR also correlated well with each other in both sets of experiments. Both SPECT planar and tomographic images showed clear uptake of {sup 131}I-FIAU in the anterolateral wall where Ad5-tk was injected. Conclusion: The study confirmed the feasibility of cardiac SPECT reporter gene imaging with HSV1-tk as a reporter gene and {sup 131}I-FIAU as a reporter probe. The optimal Ad5-tk titer for imaging was 1x10{sup 8} pfu and the optimal imaging time was 1-2 days after gene transfer. Thus, the imaging of HSV1-tk transgene expression in the heart is feasible and may be used for the noninvasive SPECT imaging of gene therapy in cardiac diseases.

Effects of cross talk on dual energy SPECT imaging between [sup 123]I-BMIPP and [sup 201]Tl

Energy Technology Data Exchange (ETDEWEB)

Morita, Masato; Narita, Hitoshi; Yamamoto, Juro; Fukutake, Naoshige; Ohyanagi, Mitsumasa; Iwasaki, Tadaaki; Fukuchi, Minoru (Hyogo College of Medicine, Nishinomiya (Japan))

1994-01-01

The study was undertaken to determine how much cross talk influences the visual assessment of dual energy single photon emission computed tomographic (SPECT) images with iodine 123 beta-methyl-p-iodophenylpentadecanoic acid (I-123 BMIPP) and thallium-201 in 15 patients with acute myocardial infarction. After single SPECT with I-123 BMIPP was undertaken, simultaneous dual SPECT with I-123 BMIPP and Tl-201 were undertaken in all patients. Three patients also underwent single SPECT with Tl-201. I-123 BMIPP and Tl-201 uptake was graded in four-score for the comparison between single and dual SPECT images. There was good correlation between dual energy SPECT and both single I-123 BMIPP SPECT (pS=0.97) and single Tl-201 SPECT (pS=0.59). Uptake scores were increased on dual energy SPECT, compared with single I-123 SPECT (8 out of 132 segments) and single Tl-201 SPECT (12 out of 36 segments). Overall, there was a comparatively well correlation between single SEPCT with either I-123 BMIPP or Tl-201 and dual energy SPECT images. However, one tracer uptake sometimes increased in the other tracer defect areas. This was noticeable when I-123 BMIPP exerted an effect on Tl-201. (N.K.).

Applicability of a set of tomographic reconstruction algorithms for quantitative SPECT on irradiated nuclear fuel assemblies

Energy Technology Data Exchange (ETDEWEB)

Jacobsson Svärd, Staffan, E-mail: staffan.jacobsson_svard@physics.uu.se; Holcombe, Scott; Grape, Sophie

2015-05-21

A fuel assembly operated in a nuclear power plant typically contains 100–300 fuel rods, depending on fuel type, which become strongly radioactive during irradiation in the reactor core. For operational and security reasons, it is of interest to experimentally deduce rod-wise information from the fuel, preferably by means of non-destructive measurements. The tomographic SPECT technique offers such possibilities through its two-step application; (1) recording the gamma-ray flux distribution around the fuel assembly, and (2) reconstructing the assembly's internal source distribution, based on the recorded radiation field. In this paper, algorithms for performing the latter step and extracting quantitative relative rod-by-rod data are accounted for. As compared to application of SPECT in nuclear medicine, nuclear fuel assemblies present a much more heterogeneous distribution of internal attenuation to gamma radiation than the human body, typically with rods containing pellets of heavy uranium dioxide surrounded by cladding of a zirconium alloy placed in water or air. This inhomogeneity severely complicates the tomographic quantification of the rod-wise relative source content, and the deduction of conclusive data requires detailed modelling of the attenuation to be introduced in the reconstructions. However, as shown in this paper, simplified models may still produce valuable information about the fuel. Here, a set of reconstruction algorithms for SPECT on nuclear fuel assemblies are described and discussed in terms of their quantitative performance for two applications; verification of fuel assemblies' completeness in nuclear safeguards, and rod-wise fuel characterization. It is argued that a request not to base the former assessment on any a priori information brings constraints to which reconstruction methods that may be used in that case, whereas the use of a priori information on geometry and material content enables highly accurate quantitative

High-resolution single photon planar and spect imaging of brain and neck employing a system of two co-registered opposed gamma imaging heads

Science.gov (United States)

Majewski, Stanislaw [Yorktown, VA; Proffitt, James [Newport News, VA

2011-12-06

A compact, mobile, dedicated SPECT brain imager that can be easily moved to the patient to provide in-situ imaging, especially when the patient cannot be moved to the Nuclear Medicine imaging center. As a result of the widespread availability of single photon labeled biomarkers, the SPECT brain imager can be used in many locations, including remote locations away from medical centers. The SPECT imager improves the detection of gamma emission from the patient's head and neck area with a large field of view. Two identical lightweight gamma imaging detector heads are mounted to a rotating gantry and precisely mechanically co-registered to each other at 180 degrees. A unique imaging algorithm combines the co-registered images from the detector heads and provides several SPECT tomographic reconstructions of the imaged object thereby improving the diagnostic quality especially in the case of imaging requiring higher spatial resolution and sensitivity at the same time.

Molecular Imaging of Hydrolytic Enzymes Using PET and SPECT.

Science.gov (United States)

Rempel, Brian P; Price, Eric W; Phenix, Christopher P

2017-01-01

Hydrolytic enzymes are a large class of biological catalysts that play a vital role in a plethora of critical biochemical processes required to maintain human health. However, the expression and/or activity of these important enzymes can change in many different diseases and therefore represent exciting targets for the development of positron emission tomography (PET) and single-photon emission computed tomography (SPECT) radiotracers. This review focuses on recently reported radiolabeled substrates, reversible inhibitors, and irreversible inhibitors investigated as PET and SPECT tracers for imaging hydrolytic enzymes. By learning from the most successful examples of tracer development for hydrolytic enzymes, it appears that an early focus on careful enzyme kinetics and cell-based studies are key factors for identifying potentially useful new molecular imaging agents.

SPECT assay of radiolabeled monoclonal antibodies. Final performance report, March 1992--November 1995

Energy Technology Data Exchange (ETDEWEB)

Jaszczak, R.J.

1995-12-01

Research is described in the following areas: development and evaluation quantitatively of reconstruction algorithms with improved compensations for attenuation, scatter, and geometric collimator response; evaluation of single photon emission computed tomography (SPECT) quantification of iodine 123 and astatine 211; and the development and evaluation of SPECT pinhole imaging for low and medium energy photons.

SPECT assay of radiolabeled monoclonal antibodies. Final performance report, March 1992--November 1995

International Nuclear Information System (INIS)

Jaszczak, R.J.

1995-12-01

Research is described in the following areas: development and evaluation quantitatively of reconstruction algorithms with improved compensations for attenuation, scatter, and geometric collimator response; evaluation of single photon emission computed tomography (SPECT) quantification of iodine 123 and astatine 211; and the development and evaluation of SPECT pinhole imaging for low and medium energy photons

Automated quantitative coronary computed tomography correlates of myocardial ischaemia on gated myocardial perfusion SPECT

International Nuclear Information System (INIS)

Graaf, Michiel A. de; Boogers, Mark J.; Veltman, Caroline E.; El-Naggar, Heba M.; Bax, Jeroen J.; Delgado, Victoria; Broersen, Alexander; Kitslaar, Pieter H.; Dijkstra, Jouke; Kroft, Lucia J.; Younis, Imad Al; Reiber, Johan H.; Scholte, Arthur J.

2013-01-01

Automated software tools have permitted more comprehensive, robust and reproducible quantification of coronary stenosis, plaque burden and plaque location of coronary computed tomography angiography (CTA) data. The association between these quantitative CTA (QCT) parameters and the presence of myocardial ischaemia has not been explored. The aim of the present investigation was to evaluate the association between QCT parameters of coronary artery lesions and the presence of myocardial ischaemia on gated myocardial perfusion single-photon emission CT (SPECT). Included in the study were 40 patients (mean age 58.2 ± 10.9 years, 27 men) with known or suspected coronary artery disease (CAD) who had undergone multidetector row CTA and gated myocardial perfusion SPECT within 6 months. From the CTA datasets, vessel-based and lesion-based visual analyses were performed. Consecutively, lesion-based QCT was performed to assess plaque length, plaque burden, percentage lumen area stenosis and remodelling index. Subsequently, the presence of myocardial ischaemia was assessed using the summed difference score (SDS ≥2) on gated myocardial perfusion SPECT. Myocardial ischaemia was seen in 25 patients (62.5 %) in 37 vascular territories. Quantitatively assessed significant stenosis and quantitatively assessed lesion length were independently associated with myocardial ischaemia (OR 7.72, 95 % CI 2.41-24.7, p 2 = 20.7) and lesion length (χ 2 = 26.0) to the clinical variables and the visual assessment (χ 2 = 5.9) had incremental value in the association with myocardial ischaemia. Coronary lesion length and quantitatively assessed significant stenosis were independently associated with myocardial ischaemia. Both quantitative parameters have incremental value over baseline variables and visually assessed significant stenosis. Potentially, QCT can refine assessment of CAD, which may be of potential use for identification of patients with myocardial ischaemia. (orig.)

Small animal SPECT and its place in the matrix of molecular imaging technologies

International Nuclear Information System (INIS)

Meikle, Steven R; Kench, Peter; Kassiou, Michael; Banati, Richard B

2005-01-01

Molecular imaging refers to the use of non-invasive imaging techniques to detect signals that originate from molecules, often in the form of an injected tracer, and observe their interaction with a specific cellular target in vivo. Differences in the underlying physical principles of these measurement techniques determine the sensitivity, specificity and length of possible observation of the signal, characteristics that have to be traded off according to the biological question under study. Here, we describe the specific characteristics of single photon emission computed tomography (SPECT) relative to other molecular imaging technologies. SPECT is based on the tracer principle and external radiation detection. It is capable of measuring the biodistribution of minute ( -10 molar) concentrations of radio-labelled biomolecules in vivo with sub-millimetre resolution and quantifying the molecular kinetic processes in which they participate. Like some other imaging techniques, SPECT was originally developed for human use and was subsequently adapted for imaging small laboratory animals at high spatial resolution for basic and translational research. Its unique capabilities include (i) the ability to image endogenous ligands such as peptides and antibodies due to the relative ease of labelling these molecules with technetium or iodine (ii) the ability to measure relatively slow kinetic processes (compared with positron emission tomography, for example) due to the long half-life of the commonly used isotopes and (iii) the ability to probe two or more molecular pathways simultaneously by detecting isotopes with different emission energies. In this paper, we review the technology developments and design tradeoffs that led to the current state-of-the-art in SPECT small animal scanning and describe the position SPECT occupies within the matrix of molecular imaging technologies. (topical review)

SPECT imaging of 131I (364 keV): importance of collimation

International Nuclear Information System (INIS)

Clarke, L.P.; Saw, C.B.; Leong, L.K.; Serafini, A.N.

1985-01-01

A low sensitivity medium energy collimator (LSMEC) designed with thick septa and long bore (theoretical leakage 131 I for a SPECT system operated in both planar and tomographic imaging modes. The collimator was designed to minimize the influence of photon penetration on spatial resolution, in particular the resolution index FWTM. Overall spatial resolution for the planar imaging mode at 10 cm from the collimator face was found to be 11.6 mm FWHM and 21.6 mm FWTM. The corresponding transverse plane and slice thickness resolution was of the order of 17 mm FWHM and 31 mm FWTM, for a radius of rotation of 16 cm. A SPECT resolution phantom was imaged. Two quadrants of cold rods were well resolved, with rod dimensions of 16 and 12.7 mm respectively, the resolution being comparable to that obtained using 99 Tcsup(m) (140 keV) and a low-energy high-resolution collimator. NEMA sensitivity obtained was 75 cpm/μCi 131 I. The resolution measurements obtained suggest that this collimator should be useful for SPECT imaging with 131 I in either radioimmunoimaging or radioimmunotherapy. (author)

Assessment of left ventricular function by thallium-201 quantitative gated cardiac SPECT

International Nuclear Information System (INIS)

Baba, Akira; Hano, Takuzo; Ohmori, Hisashi; Ibata, Masayo; Kawabe, Tetsuya; Kubo, Takashi; Kimura, Keizo; Nishio, Ichiro

2002-01-01

Present study was designed to evaluate the accuracy of the measurement of left ventricular volume by quantitative gated SPECT (QGS) software using 201 Tl and the effect of cutoff frequency of Butterworth prereconstruction filter on the calculation of volume. The RH-2 type cardiac phantom and 20 patients with ischemic heart disease were studied. Left ventricular end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) were calculated by the QGS software using the various frequency of Butterworth filter. These parameters were evaluated by Simpson's method using left ventriculography (LVG). The volume of the phantom calculated by QGS was under-estimated by 14%. In the clinical study, EDV and ESV measured by QGS were smaller than those obtained from LVG by 10%. When the cutoff frequency of Butterworth filter was 0.43 cycles/cm, the values measured by QGS were best correlated with those by LVG (EDV: r=0.80, p 201 Tl quantitative gated cardiac SPECT can estimate myocardial ischemia and left ventricular function simultaneously. (author)

SPECT in psychiatry. SPECT in der Psychiatrie

Energy Technology Data Exchange (ETDEWEB)

Barocka, A. (Psychiatrische Klinik und Poliklinik, Erlangen (Germany)); Feistel, H. (Nuklearmedizinische Klinik, Erlangen (Germany)); Ebert, D. (Psychiatrische Klinik und Poliklinik, Erlangen (Germany)); Lungershausen, E. (Psychiatrische Klinik und Poliklinik, Erlangen (Germany))

1993-08-13

This review presents Single Photon Emission Computed Tomography (SPECT) as a powerful tool for clinical use and research in psychiatry. Its focus is on regional cerebral blood flow, measured with technetium labelled HMPAO. In addition, first results with brain receptor imaging, concerning dopamin-D[sub 2] and benzodiazepine receptors, are covered. Due to major improvements in image quality, and impressive number of results has been accumulated in the past three years. The authors caution against using SPECT results as markers for disease entities. A finding like 'hypofrontality' is considered typical of a variety of mental disorders. Clearly both, more experience with SPECT and contributions from psychopathology, are needed. (orig.)

GATE simulation of a new design of pinhole SPECT system for small animal brain imaging

International Nuclear Information System (INIS)

Ozsahin, D. Uzun; Bläckberg, L.; Fakhri, G. El; Sabet, H.

2017-01-01

Small animal SPECT imaging has gained an increased interest over the past decade since it is an excellent tool for developing new drugs and tracers. Therefore, there is a huge effort on the development of cost-effective SPECT detectors with high capabilities. The aim of this study is to simulate the performance characteristics of new designs for a cost effective, stationary SPECT system dedicated to small animal imaging with a focus on mice brain. The conceptual design of this SPECT system platform, Stationary Small Animal SSA-SPECT, is to use many pixelated CsI:TI detector modules with 0.4 mm × 0.4 mm pixels in order to achieve excellent intrinsic detector resolution where each module is backed by a single pinhole collimator with 0.3 mm hole diameter. In this work, we present the simulation results of four variations of the SSA-SPECT platform where the number of detector modules and FOV size is varied while keeping the detector size and collimator hole size constant. Using the NEMA NU-4 protocol, we performed spatial resolution, sensitivity, image quality simulations followed by a Derenzo-like phantom evaluation. The results suggest that all four SSA-SPECT systems can provide better than 0.063% system sensitivity and < 1.5 mm FWHM spatial resolution without resolution recovery or other correction techniques. Specifically, SSA-SPECT-1 showed a system sensitivity of 0.09% in combination with 1.1 mm FWHM spatial resolution.

A Silicon SPECT System for Molecular Imaging of the Mouse Brain.

Science.gov (United States)

Shokouhi, Sepideh; Fritz, Mark A; McDonald, Benjamin S; Durko, Heather L; Furenlid, Lars R; Wilson, Donald W; Peterson, Todd E

2007-01-01

We previously demonstrated the feasibility of using silicon double-sided strip detectors (DSSDs) for SPECT imaging of the activity distribution of iodine-125 using a 300-micrometer thick detector. Based on this experience, we now have developed fully customized silicon DSSDs and associated readout electronics with the intent of developing a multi-pinhole SPECT system. Each DSSD has a 60.4 mm × 60.4 mm active area and is 1 mm thick. The strip pitch is 59 micrometers, and the readout of the 1024 strips on each side gives rise to a detector with over one million pixels. Combining four high-resolution DSSDs into a SPECT system offers an unprecedented space-bandwidth product for the imaging of single-photon emitters. The system consists of two camera heads with two silicon detectors stacked one behind the other in each head. The collimator has a focused pinhole system with cylindrical-shaped pinholes that are laser-drilled in a 250 μm tungsten plate. The unique ability to collect projection data at two magnifications simultaneously allows for multiplexed data at high resolution to be combined with lower magnification data with little or no multiplexing. With the current multi-pinhole collimator design, our SPECT system will be capable of offering high spatial resolution, sensitivity and angular sampling for small field-of-view applications, such as molecular imaging of the mouse brain.

Ictal and interictal SPECT imaging of 8 patients with symptomatic partial epilepsy

International Nuclear Information System (INIS)

Motooka, Hiromichi

1993-01-01

Although epileptic discharges such as spike, spike and wave complex, sharp wave, and sharp and wave complex can be recorded by interictal scalp electroencephalography (EEG) in many patients with epilepsy, recent studies have demonstrated that no epileptic discharges can be recorded by interictal and ictal scalp EEGs in some patients who clinically exhibit epileptic seizures. Accordingly scalp EEG is not always helpful for diagnosing epilepsy or identifying the epileptic foci in the brain in these patients. Recently, studies using single photon emission computed tomography (SPECT) have been performed for patients with epilepsy and evidence that epileptic foci can be identified by changes in the regional cerebral blood flow (rCBF) seen on SPECT scanning have been accumulated. In the present study, therefore, 8 patients with medically intractable partial seizures were simultaneously or independently investigated by the recordings of scalp EEG and SPECT scanning during the interictal and ictal period. N-isopropyl-p[ 123 I]-iodoamphetamine ( 123 I-IMP) was used for SPECT scanning for 7 patients and 99m Tc-d,l-hexamethyl-propyleneamineoxime ( 99m Tc-HMPAO) for 1 patient. An increase in rCBF (hyperperfusion) or decrease in rCBF (hypoperfusion) were found in 4 patients by interictal SPECT imaging and in all patients by ictal SPECT imaging although epileptic discharges were observed in 3 patients by interictal scalp EEG and 5 patients by ictal scalp EEG. The findings of the present study indicate that ictal SPECT scanning is more useful for diagnosing epilepsy and identifying the epileptic foci in the brain than ictal scalp EEG. (author)

Influences of reconstruction and attenuation correction in brain SPECT images obtained by the hybrid SPECT/CT device: evaluation with a 3-dimensional brain phantom

International Nuclear Information System (INIS)

Akamatsu, Mana; Yamashita, Yasuo; Akamatsu, Go; Tsutsui, Yuji; Ohya, Nobuyoshi; Nakamura, Yasuhiko; Sasaki, Masayuki

2014-01-01

The aim of this study was to evaluate the influences of reconstruction and attenuation correction on the differences in the radioactivity distributions in 123 I brain SPECT obtained by the hybrid SPECT/CT device. We used the 3-dimensional (3D) brain phantom, which imitates the precise structure of gray matter, white matter and bone regions. It was filled with 123 I solution (20.1 kBq/mL) in the gray matter region and with K 2 HPO 4 in the bone region. The SPECT/CT data were acquired by the hybrid SPECT/CT device. SPECT images were reconstructed by using filtered back projection with uniform attenuation correction (FBP-uAC), 3D ordered-subsets expectation-maximization with uniform AC (3D-OSEM-uAC) and 3D OSEM with CT-based non-uniform AC (3D-OSEM-CTAC). We evaluated the differences in the radioactivity distributions among these reconstruction methods using a 3D digital phantom, which was developed from CT images of the 3D brain phantom, as a reference. The normalized mean square error (NMSE) and regional radioactivity were calculated to evaluate the similarity of SPECT images to the 3D digital phantom. The NMSE values were 0.0811 in FBP-uAC, 0.0914 in 3D-OSEM-uAC and 0.0766 in 3D-OSEM-CTAC. The regional radioactivity of FBP-uAC was 11.5% lower in the middle cerebral artery territory, and that of 3D-OSEM-uAC was 5.8% higher in the anterior cerebral artery territory, compared with the digital phantom. On the other hand, that of 3D-OSEM-CTAC was 1.8% lower in all brain areas. By using the hybrid SPECT/CT device, the brain SPECT reconstructed by 3D-OSEM with CT attenuation correction can provide an accurate assessment of the distribution of brain radioactivity

Preoperative localization of epileptic foci with SPECT brain perfusion imaging, electrocorticography, surgery and pathology

International Nuclear Information System (INIS)

Jia Shaowei; Xu Wengui; Chen Hongyan; Weng Yongmei; Yang Pinghua

2002-01-01

Objective: The value of preoperative localization of epileptic foci with SPECT brain perfusion imaging was investigated. Methods: The study population consisted of 23 patients with intractable partial seizures which was difficult to control with anticonvulsant for long period. In order to preoperatively locate the epileptic foci, double SPECT brain perfusion imaging was performed during interictal and ictal stage. The foci were confirmed with electrocorticography (EcoG), surgery and pathology. Results: The author checked with EcoG the foci shown by SPECT, 23 patients had all typical spike discharge. The regions of radioactivity increase in ictal matched with the abnormal electrical activity areas that EcoG showed. The spike wave originated in the corresponding cerebrum cortex instead of hyperplastic and adherent arachnoid or tumor itself. Conclusions: SPECT brain perfusion imaging contributes to distinguishing location, size, perfusion and functioning of epileptogenic foci, and has some directive function on to making out a treatment programme at preoperation

Examination of statistical noise in SPECT image and sampling pitch

International Nuclear Information System (INIS)

Takaki, Akihiro; Soma, Tsutomu; Murase, Kenya; Watanabe, Hiroyuki; Murakami, Tomonori; Kawakami, Kazunori; Teraoka, Satomi; Kojima, Akihiro; Matsumoto, Masanori

2008-01-01

Statistical noise in single photon emission computed tomography (SPECT) image was examined for its relation with total count and with sampling pitch by simulation and phantom experiment to obtain their projection data under defined conditions. The former SPECT simulation was performed on assumption of a virtual, homogeneous water column (20 cm diameter) as an absorbing mass. In the latter, used were 3D-Hoffman brain phantom (Data Spectrum Corp.) filled with 370 MBq of 99m Tc-pertechnetate solution and a facing 2-detector SPECT machine with a low-energy/high-resolution collimator, E-CAM (Siemens). Projected data by the two methods were reconstructed through the filtered back projection to make each transaxial image. The noise was evaluated by vision, by their root mean square uncertainty calculated from average count and standard deviation (SD) in the region of interest (ROI) defined in reconstructed images and by normalized mean squares calculated from the difference between the reference image obtained with common sampling pitch to and all of obtained slices of, the simulation and phantom. As a conclusion, the pitch was recommended to be set in the machine as to approximating the value calculated by the sampling theorem, though the projection counts per one angular direction were smaller with the same total time of data acquisition. (R.T.)

Performance evaluation of a compact PET/SPECT/CT tri-modality system for small animal imaging applications

International Nuclear Information System (INIS)

Wei, Qingyang; Wang, Shi; Ma, Tianyu; Wu, Jing; Liu, Hui; Xu, Tianpeng; Xia, Yan; Fan, Peng; Lyu, Zhenlei; Liu, Yaqiang

2015-01-01

PET, SPECT and CT imaging techniques are widely used in preclinical small animal imaging applications. In this paper, we present a compact small animal PET/SPECT/CT tri-modality system. A dual-functional, shared detector design is implemented which enables PET and SPECT imaging with a same LYSO ring detector. A multi-pinhole collimator is mounted on the system and inserted into the detector ring in SPECT imaging mode. A cone-beam CT consisting of a micro focus X-ray tube and a CMOS detector is implemented. The detailed design and the performance evaluations are reported in this paper. In PET imaging mode, the measured NEMA based spatial resolution is 2.12 mm (FWHM), and the sensitivity at the central field of view (CFOV) is 3.2%. The FOV size is 50 mm (∅)×100 mm (L). The SPECT has a spatial resolution of 1.32 mm (FWHM) and an average sensitivity of 0.031% at the center axial, and a 30 mm (∅)×90 mm (L) FOV. The CT spatial resolution is 8.32 lp/mm @10%MTF, and the contrast discrimination function value is 2.06% with 1.5 mm size cubic box object. In conclusion, a compact, tri-modality PET/SPECT/CT system was successfully built with low cost and high performance

TU-A-12A-02: Novel Lung Ventilation Imaging with Single Energy CT After Single Inhalation of Xenon: Comparison with SPECT Ventilation Images

Energy Technology Data Exchange (ETDEWEB)

Negahdar, M [Stanford University School of Medicine, Stanford, CA (United States); Yamamoto, T [UC Davis School of Medicine, Sacramento, CA (United States); Shultz, D; Gable, L; Shan, X; Mittra, E; Loo, B; Maxim, P [Stanford University, Stanford, CA (United States); Diehn, M [Stanford University, Palo Alto, CA (United States)

2014-06-15

Purpose: We propose a novel lung functional imaging method to determine the spatial distribution of xenon (Xe) gas in a single inhalation as a measure of regional ventilation. We compare Xe-CT ventilation to single-photon emission CT (SPECT) ventilation, which is the current clinical reference. Regional lung ventilation information may be useful for the diagnosis and monitoring of pulmonary diseases such as COPD, radiotherapy planning, and assessing the progression of toxicity after radiation therapy. Methods: In an IRB-approved clinical study, Xe-CT and SPECT ventilation scans were acquired for three patients including one patient with severe emphysema and two lung cancer patients treated with radiotherapy. For Xe- CT, we acquired two breath-hold single energy CT images of the entire lung with inspiration of 100% O2 and a mixture of 70% Xe and 30% O2, respectively. A video biofeedback system was used to achieve reproducible breath-holds. We used deformable image registration to align the breathhold images with each other to accurately subtract them, producing a map of the distribution of Xe as a surrogate of lung ventilation. We divided each lung into twelve parts and correlated the Hounsfield unit (HU) enhancement at each part with the SPECT ventilation count of the corresponding part of the lung. Results: The mean of the Pearson linear correlation coefficient values between the Xe-CT and ventilation SPECT count for all three patients were 0.62 (p<0.01). The Xe-CT image had a higher resolution than SPECT, and did not show central airway deposition artifacts that were present in the SPECT image. Conclusion: We developed a rapid, safe, clinically practical, and potentially widely accessible method for regional lung functional imaging. We demonstrated strong correlations between the Xe-CT ventilation image and SPECT ventilation image as the clinical reference. This ongoing study will investigate more patients to confirm this finding.

TU-A-12A-02: Novel Lung Ventilation Imaging with Single Energy CT After Single Inhalation of Xenon: Comparison with SPECT Ventilation Images

International Nuclear Information System (INIS)

Negahdar, M; Yamamoto, T; Shultz, D; Gable, L; Shan, X; Mittra, E; Loo, B; Maxim, P; Diehn, M

2014-01-01

Purpose: We propose a novel lung functional imaging method to determine the spatial distribution of xenon (Xe) gas in a single inhalation as a measure of regional ventilation. We compare Xe-CT ventilation to single-photon emission CT (SPECT) ventilation, which is the current clinical reference. Regional lung ventilation information may be useful for the diagnosis and monitoring of pulmonary diseases such as COPD, radiotherapy planning, and assessing the progression of toxicity after radiation therapy. Methods: In an IRB-approved clinical study, Xe-CT and SPECT ventilation scans were acquired for three patients including one patient with severe emphysema and two lung cancer patients treated with radiotherapy. For Xe- CT, we acquired two breath-hold single energy CT images of the entire lung with inspiration of 100% O2 and a mixture of 70% Xe and 30% O2, respectively. A video biofeedback system was used to achieve reproducible breath-holds. We used deformable image registration to align the breathhold images with each other to accurately subtract them, producing a map of the distribution of Xe as a surrogate of lung ventilation. We divided each lung into twelve parts and correlated the Hounsfield unit (HU) enhancement at each part with the SPECT ventilation count of the corresponding part of the lung. Results: The mean of the Pearson linear correlation coefficient values between the Xe-CT and ventilation SPECT count for all three patients were 0.62 (p<0.01). The Xe-CT image had a higher resolution than SPECT, and did not show central airway deposition artifacts that were present in the SPECT image. Conclusion: We developed a rapid, safe, clinically practical, and potentially widely accessible method for regional lung functional imaging. We demonstrated strong correlations between the Xe-CT ventilation image and SPECT ventilation image as the clinical reference. This ongoing study will investigate more patients to confirm this finding

Automated quantitative coronary computed tomography correlates of myocardial ischaemia on gated myocardial perfusion SPECT

Energy Technology Data Exchange (ETDEWEB)

Graaf, Michiel A. de; Boogers, Mark J.; Veltman, Caroline E. [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands); The Interuniversity Cardiology Institute of The Netherlands, Utrecht (Netherlands); El-Naggar, Heba M.; Bax, Jeroen J.; Delgado, Victoria [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands); Broersen, Alexander; Kitslaar, Pieter H.; Dijkstra, Jouke [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Kroft, Lucia J. [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Younis, Imad Al [Leiden University Medical Center, Department of Nuclear Medicine, Leiden (Netherlands); Reiber, Johan H. [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Medis medical imaging systems B.V., Leiden (Netherlands); Scholte, Arthur J. [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands)

2013-08-15

Automated software tools have permitted more comprehensive, robust and reproducible quantification of coronary stenosis, plaque burden and plaque location of coronary computed tomography angiography (CTA) data. The association between these quantitative CTA (QCT) parameters and the presence of myocardial ischaemia has not been explored. The aim of the present investigation was to evaluate the association between QCT parameters of coronary artery lesions and the presence of myocardial ischaemia on gated myocardial perfusion single-photon emission CT (SPECT). Included in the study were 40 patients (mean age 58.2 {+-} 10.9 years, 27 men) with known or suspected coronary artery disease (CAD) who had undergone multidetector row CTA and gated myocardial perfusion SPECT within 6 months. From the CTA datasets, vessel-based and lesion-based visual analyses were performed. Consecutively, lesion-based QCT was performed to assess plaque length, plaque burden, percentage lumen area stenosis and remodelling index. Subsequently, the presence of myocardial ischaemia was assessed using the summed difference score (SDS {>=}2) on gated myocardial perfusion SPECT. Myocardial ischaemia was seen in 25 patients (62.5 %) in 37 vascular territories. Quantitatively assessed significant stenosis and quantitatively assessed lesion length were independently associated with myocardial ischaemia (OR 7.72, 95 % CI 2.41-24.7, p < 0.001, and OR 1.07, 95 % CI 1.00-1.45, p = 0.032, respectively) after correcting for clinical variables and visually assessed significant stenosis. The addition of quantitatively assessed significant stenosis ({chi} {sup 2} = 20.7) and lesion length ({chi} {sup 2} = 26.0) to the clinical variables and the visual assessment ({chi} {sup 2} = 5.9) had incremental value in the association with myocardial ischaemia. Coronary lesion length and quantitatively assessed significant stenosis were independently associated with myocardial ischaemia. Both quantitative parameters have

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.)

Introduction of a novel ultrahigh sensitivity collimator for brain SPECT imaging

Energy Technology Data Exchange (ETDEWEB)

Park, Mi-Ae, E-mail: miaepark@bwh.harvard.edu; Kijewski, Marie Foley; Lyon, Morgan C.; Horky, Laura; Moore, Stephen C. [Department of Radiology, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts 02115 (United States); Keijzers, Ronnie; Keijzers, Mark [Nuclear Fields USA, Des Plaines, Illinois 60018 (United States)

2016-08-15

Purpose: Noise levels of brain SPECT images are highest in central regions, due to preferential attenuation of photons emitted from deep structures. To address this problem, the authors have designed a novel collimator for brain SPECT imaging that yields greatly increased sensitivity near the center of the brain without loss of resolution. This hybrid collimator consisted of ultrashort cone-beam holes in the central regions and slant-holes in the periphery (USCB). We evaluated this collimator for quantitative brain imaging tasks. Methods: Owing to the uniqueness of the USCB collimation, the hole pattern required substantial variations in collimator parameters. To utilize the lead-casting technique, the authors designed two supporting plates to position about 37 000 hexagonal, slightly tapered pins. The holes in the supporting plates were modeled to yield the desired focal length, hole length, and septal thickness. To determine the properties of the manufactured collimator and to compute the system matrix, the authors prepared an array of point sources that covered the entire detector area. Each point source contained 32 μCi of Tc-99m at the first scan time. The array was imaged for 5 min at each of the 64 shifted locations to yield a 2-mm sampling distance, and hole parameters were calculated. The sensitivity was also measured using a point source placed along the central ray at several distances from the collimator face. High-count projection data from a five-compartment brain phantom were acquired with the three collimators on a dual-head SPECT/CT system. The authors calculated Cramer-Rao bounds on the precision of estimates of striatal and background activity concentration. In order to assess the new collimation system to detect changes in striatal activity, the authors evaluated the precision of measuring a 5% decrease in right putamen activity. The authors also reconstructed images of projection data obtained by summing data from the individual phantom

Comparison of diagnostic value of coronary artery disease between ATP-stress and exercise-stress thallium myocardial SPECT images

International Nuclear Information System (INIS)

Suzuki, Shigeo

1994-01-01

A study was made between adenosine triphosphate disodium (ATP)-stress thallium myocardial scintigrams and exercise-stress scintigrams to compare their respective extents and degree of defects. The subjects of the study were 33 ischemic heart disease patients, who received ATP stress and treadmill exercise stress with a mean interval of 25 days. ATP was infused for 5 minutes with an infusion rate of 0.16 or 0.18 mg per kg of body weight per minute. Thallium was injected three minutes after infusion. The percent-defect index (percentage of the extent and degree of the defects for all 33 patients), was calculated with visual scoring using a five-zone myocardial division method and semi-quantitative four-grade representation method for both the ATP and exercise SPECT images. The extent of the defects in ATP- and exercise-stress images was 51.5% and 44.2%, and that in redistribution images was 36.4% and 33.9%, respectively. The degree of defects in ATP- and exercise-stress images was 35.8% and 32.3%, while that in redistribution images was 20.8% and 17.2%, respectively (p=NS in all cases). In conclusion, the image quality of thallium SPECT with ATP stress was equivalent that of exercise stress, indicating identical diagnostic values for coronary lesions. (author)

Quantification of GABAA receptors in the rat brain with [123I]Iomazenil SPECT from factor analysis-denoised images

International Nuclear Information System (INIS)

Tsartsalis, Stergios; Moulin-Sallanon, Marcelle; Dumas, Noé; Tournier, Benjamin B.; Ghezzi, Catherine; Charnay, Yves; Ginovart, Nathalie; Millet, Philippe

2014-01-01

Purpose: In vivo imaging of GABA A receptors is essential for the comprehension of psychiatric disorders in which the GABAergic system is implicated. Small animal SPECT provides a modality for in vivo imaging of the GABAergic system in rodents using [ 123 I]Iomazenil, an antagonist of the GABA A receptor. The goal of this work is to describe and evaluate different quantitative reference tissue methods that enable reliable binding potential (BP) estimations in the rat brain to be obtained. Methods: Five male Sprague–Dawley rats were used for [ 123 I]Iomazenil brain SPECT scans. Binding parameters were obtained with a one-tissue compartment model (1TC), a constrained two-tissue compartment model (2TC c ), the two-step Simplified Reference Tissue Model (SRTM2), Logan graphical analysis and analysis of delayed-activity images. In addition, we employed factor analysis (FA) to deal with noise in data. Results: BP ND obtained with SRTM2, Logan graphical analysis and delayed-activity analysis was highly correlated with BP F values obtained with 2TC c (r = 0.954 and 0.945 respectively, p c and SRTM2 in raw and FA-denoised images (r = 0.961 and 0.909 respectively, p ND values from raw images while scans of only 70 min are sufficient from FA-denoised images. These images are also associated with significantly lower standard errors of 2TC c and SRTM2 BP values. Conclusion: Reference tissue methods such as SRTM2 and Logan graphical analysis can provide equally reliable BP ND values from rat brain [ 123 I]Iomazenil SPECT. Acquisitions, however, can be much less time-consuming either with analysis of delayed activity obtained from a 20-minute scan 50 min after tracer injection or with FA-denoising of images

Resting functional imaging tools (MRS, SPECT, PET and PCT).

Science.gov (United States)

Van Der Naalt, J

2015-01-01

Functional imaging includes imaging techniques that provide information about the metabolic and hemodynamic status of the brain. Most commonly applied functional imaging techniques in patients with traumatic brain injury (TBI) include magnetic resonance spectroscopy (MRS), single photon emission computed tomography (SPECT), positron emission tomography (PET) and perfusion CT (PCT). These imaging modalities are used to determine the extent of injury, to provide information for the prediction of outcome, and to assess evidence of cerebral ischemia. In TBI, secondary brain damage mainly comprises ischemia and is present in more than 80% of fatal cases with traumatic brain injury (Graham et al., 1989; Bouma et al., 1991; Coles et al., 2004). In particular, while SPECT measures cerebral perfusion and MRS determines metabolism, PET is able to assess both perfusion and cerebral metabolism. This chapter will describe the application of these techniques in traumatic brain injury separately for the major groups of severity comprising the mild and moderate to severe group. The application in TBI and potential difficulties of each technique is described. The use of imaging techniques in children will be separately outlined. © 2015 Elsevier B.V. All rights reserved.

Feasibility of Stereo-Infrared Tracking to Monitor Patient Motion During Cardiac SPECT Imaging

OpenAIRE

Beach, Richard D.; Pretorius, P. Hendrik; Boening, Guido; Bruyant, Philippe P.; Feng, Bing; Fulton, Roger R.; Gennert, Michael A.; Nadella, Suman; King, Michael A.

2004-01-01

Patient motion during cardiac SPECT imaging can cause diagnostic imaging artifacts. We investigated the feasibility of monitoring patient motion using the Polaris motion-tracking system. This system uses passive infrared reflection from small spheres to provide real-time position data with vendor stated 0.35 mm accuracy and 0.2 mm repeatability. In our configuration, the Polaris system views through the SPECT gantry toward the patient's head. List-mode event data was temporally synchronized w...

Clinical application of SPECT in adrenal imaging with iodine-131 6 beta-iodomethyl-19-norcholesterol

International Nuclear Information System (INIS)

Ishimura, J.; Kawanaka, M.; Fukuchi, M.

1989-01-01

Forty-one patients with or without adrenocortical disorders were studied to evaluate the clinical usefulness of SPECT in adrenal imaging with I-131 Adosterol. In the SPECT images from this study, all glands with either normally functioning or hyperfunctioning adrenal cortices could be detected, while those glands with hypofunctioning adrenal cortices could not be detected. Particularly in transaxial and sagittal slices, the adrenal gland was identified posteriorly and was clearly distinguished from the gallbladder. In preliminary results using SPECT by a standard method, uptake in 68 detectable glands ranged from 1.7% to 4.9% in four glands with Cushing's syndrome, from 1.1% to 1.3% in seven glands with primary aldosteronism, and were distributed below 1.0% in the remaining glands with normally functioning adrenal cortices. These data show that it is possible to evaluate the adrenocortical functioning status simply by analyzing the SPECT images of the adrenal

MO-DE-303-03: Session on quantitative imaging for assessment of tumor response to radiation therapy

International Nuclear Information System (INIS)

Bowen, S.

2015-01-01

This session will focus on quantitative imaging for assessment of tumor response to radiation therapy. This is a technically challenging method to translate to practice in radiation therapy. In the new era of precision medicine, however, delivering the right treatment, to the right patient, and at the right time, can positively impact treatment choices and patient outcomes. Quantitative imaging provides the spatial sensitivity required by radiation therapy for precision medicine that is not available by other means. In this Joint ESTRO -AAPM Symposium, three leading-edge investigators will present specific motivations for quantitative imaging biomarkers in radiation therapy of esophageal, head and neck, locally advanced non-small cell lung cancer, and hepatocellular carcinoma. Experiences with the use of dynamic contrast enhanced (DCE) MRI, diffusion- weighted (DW) MRI, PET/CT, and SPECT/CT will be presented. Issues covered will include: response prediction, dose-painting, timing between therapy and imaging, within-therapy biomarkers, confounding effects, normal tissue sparing, dose-response modeling, and association with clinical biomarkers and outcomes. Current information will be presented from investigational studies and clinical practice. Learning Objectives: Learn motivations for the use of quantitative imaging biomarkers for assessment of response to radiation therapy Review the potential areas of application in cancer therapy Examine the challenges for translation, including imaging confounds and paucity of evidence to date Compare exemplary examples of the current state of the art in DCE-MRI, DW-MRI, PET/CT and SPECT/CT imaging for assessment of response to radiation therapy Van der Heide: Research grants from the Dutch Cancer Society and the European Union (FP7) Bowen: RSNA Scholar grant

MO-DE-303-03: Session on quantitative imaging for assessment of tumor response to radiation therapy

Energy Technology Data Exchange (ETDEWEB)

Bowen, S. [University of Washington, School of Medicine: PET/CT and SPECT/CT for Lung and Liver Radiation Therapy Response Assessment of Tumor and Normal Tissue (United States)

2015-06-15

This session will focus on quantitative imaging for assessment of tumor response to radiation therapy. This is a technically challenging method to translate to practice in radiation therapy. In the new era of precision medicine, however, delivering the right treatment, to the right patient, and at the right time, can positively impact treatment choices and patient outcomes. Quantitative imaging provides the spatial sensitivity required by radiation therapy for precision medicine that is not available by other means. In this Joint ESTRO -AAPM Symposium, three leading-edge investigators will present specific motivations for quantitative imaging biomarkers in radiation therapy of esophageal, head and neck, locally advanced non-small cell lung cancer, and hepatocellular carcinoma. Experiences with the use of dynamic contrast enhanced (DCE) MRI, diffusion- weighted (DW) MRI, PET/CT, and SPECT/CT will be presented. Issues covered will include: response prediction, dose-painting, timing between therapy and imaging, within-therapy biomarkers, confounding effects, normal tissue sparing, dose-response modeling, and association with clinical biomarkers and outcomes. Current information will be presented from investigational studies and clinical practice. Learning Objectives: Learn motivations for the use of quantitative imaging biomarkers for assessment of response to radiation therapy Review the potential areas of application in cancer therapy Examine the challenges for translation, including imaging confounds and paucity of evidence to date Compare exemplary examples of the current state of the art in DCE-MRI, DW-MRI, PET/CT and SPECT/CT imaging for assessment of response to radiation therapy Van der Heide: Research grants from the Dutch Cancer Society and the European Union (FP7) Bowen: RSNA Scholar grant.

Triple Detector SPECT Imaging with 99mTc-DMSA in Adult Patients with Urinary Tract Infection

International Nuclear Information System (INIS)

Ryu, Jin Sook; Bea, Woon Gyu; Moon, Dae Hyuk; Lee, Myung Hae; Kim, Soon Bae; Park, Su Kil; Park, Jung Sik; Hong, Chang Gi; Cho, Kyung Sik

1992-01-01

Although early diagnosis of urinary tract infection is important, the radiologic evaluation is still controversial because of the low sensitivity and the lack of cost-effectiveness. This study was carried out to evaluate the clinical utility of high resolution triple head 99m Tc-DMSA SPECT imaging in urinary tract infection. We prospectively performed 99m Tc-DMSA planar and SPECT imaging, ultrasound of kidney (US), intravenous pyelography (IVP) and voiding cystourethrography (VCU) in all 60 adult patients with UTI [26 with first episode of acute pyelonephritis (APN), 22 with recurrent APN, and 12 persistent asymptomatic pyuria] and 25 normal persons. To assess reversibility of the renal cortical defect (RCD), 99m Tc-DMSA SPECT was repeated 1 to 8 months later in those patients with abnormal initial findings. Overall detection rate of 99m Tc-DMSA SPECT imaging was 83% (50/60), but planar, US, IVP and VCU showed abnormal findings in 68%, 28%, 32% and 13%, respectively. 25 out of 27 patients with normal or single RCD were all normal in other radiological studies. Only two patients showed vesicoureteral reflux (VUR) on VCU (grade I) and mild hydronephrosis on IVP. But, high proportion of those with multiple RCD showed abnormal findings on US (17/33), IVP (18/33), and VCU (7/33): 67% in any of these 3 studies. Especially, 3 out 7 patients with VUR showed multiple RCD on 99m Tc-DMSA SPECT without any abnormality on IVP or US. 25 normal persons showed normal findings in all studies except one false positive finding on 99m Tc-DMSA SPECT imaging. Follow-up 99m Tc-DMSA SPECT was done in 28 patients (13 with single RCD, 15 with multiple RCD). All 13 patients with single RCD showed improvement. Those with multiple RCD presented improvement in 4, no change in 10, and aggravation in 1 on follow-up studies. With these results, we conclude: 1) 99m Tc-DMSA SPECT imaging is superior to planar imaging, US, IVP or VCU in detection of renal lesion in urinary tract infection. 99m Tc

[Segmentation of whole body bone SPECT image based on BP neural network].

Science.gov (United States)

Zhu, Chunmei; Tian, Lianfang; Chen, Ping; He, Yuanlie; Wang, Lifei; Ye, Guangchun; Mao, Zongyuan

2007-10-01

In this paper, BP neural network is used to segment whole body bone SPECT image so that the lesion area can be recognized automatically. For the uncertain characteristics of SPECT images, it is hard to achieve good segmentation result if only the BP neural network is employed. Therefore, the segmentation process is divided into three steps: first, the optimal gray threshold segmentation method is employed for preprocessing, then BP neural network is used to roughly identify the lesions, and finally template match method and symmetry-removing program are adopted to delete the wrongly recognized areas.

Physiological imaging with PET and SPECT in Dementia

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Jagust, W.J. (California Univ., San Francisco, CA (United States). Dept. of Neurology Lawrence Berkeley Lab., CA (United States))

1989-10-01

Dementia is a medical problem of increasingly obvious importance. The most common cause of dementia, Alzheimer's disease (AD) accounts for at least 50% of all cases of dementia, with multi-infarct dementia the next most common cause of the syndrome. While the accuracy of diagnosis of AD may range from 80 to 90%, there is currently no laboratory test to confirm the diagnosis. Functional imaging techniques such as positron emission tomography (PET) and single photon emission computed tomography (SPECT) offer diagnostic advantages since brain function is unequivocally disturbed in all dementing illnesses. Both PET and SPECT have been utilized in the study of dementia. While both techniques rely on principles of emission tomography to produce three dimensional maps of injected radiotracers, the differences between positron and single photon emission have important consequences for the practical applications of the two procedures. This briefly reviews the technical differences between PET and SPECT, and discusses how both techniques have been used in our laboratory to elucidate the pathophysiology of dementia. 32 refs., 2 figs.

Physiological imaging with PET and SPECT in Dementia

International Nuclear Information System (INIS)

Jagust, W.J.

1989-10-01

Dementia is a medical problem of increasingly obvious importance. The most common cause of dementia, Alzheimer's disease (AD) accounts for at least 50% of all cases of dementia, with multi-infarct dementia the next most common cause of the syndrome. While the accuracy of diagnosis of AD may range from 80 to 90%, there is currently no laboratory test to confirm the diagnosis. Functional imaging techniques such as positron emission tomography (PET) and single photon emission computed tomography (SPECT) offer diagnostic advantages since brain function is unequivocally disturbed in all dementing illnesses. Both PET and SPECT have been utilized in the study of dementia. While both techniques rely on principles of emission tomography to produce three dimensional maps of injected radiotracers, the differences between positron and single photon emission have important consequences for the practical applications of the two procedures. This briefly reviews the technical differences between PET and SPECT, and discusses how both techniques have been used in our laboratory to elucidate the pathophysiology of dementia. 32 refs., 2 figs

Differential impact of multi-focus fan beam collimation with L-mode and conventional systems on the accuracy of myocardial perfusion imaging: Quantitative evaluation using phantoms

International Nuclear Information System (INIS)

Onishi, Hideo; Matsutomo, Norikazu; Kangai, Yoshiharu; Saho, Tatsunori; Amijima, Hizuru

2013-01-01

A novel IQ-SPECT™ method has become widely used in clinical studies. The present study compares the quality of myocardial perfusion images (MPI) acquired using the IQ-SPECT™ (IQ-mode), conventional (180° apart: C-mode) and L-mode (90° apart: L-mode) systems. We assessed spatial resolution, image reproducibility and quantifiability using various physical phantoms. SPECT images were acquired using a dual-headed gamma camera with C-mode, L-mode, and IQ-mode acquisition systems from line source, pai and cardiac phantoms containing solutions of 99m Tc. The line source phantom was placed in the center of the orbit and at ± 4.0, ± 8.0, ± 12.0, ± 16.0 and ± 20.0 cm off center. We examined quantifiability using the pai phantom comprising six chambers containing 0.0, 0.016, 0.03, 0.045, 0.062, and 0.074 MBq/mL of 99m-Tc and cross-calibrating the SPECT counts. Image resolution and reproducibility were quantified as myocardial wall thickness (MWT) and %uptake using polar maps. The full width at half maximum (FWHM) of the IQ-mode in the center was increased by 11% as compared with C-mode, and FWHM in the periphery was increased 41% compared with FWHM at the center. Calibrated SPECT counts were essentially the same when quantified using IQ-and C-modes. IQ-SPECT images of MWT were significantly improved (P<0.001) over L-mode, and C-mode SPECT imaging with IQ-mode became increasingly inhomogeneous, both visually and quantitatively (C-mode vs. L-mode, ns; C-mode vs. IQ-mode, P<0.05). Myocardial perfusion images acquired by IQ-SPECT were comparable to those acquired by conventional and L-mode SPECT, but with significantly improved resolution and quality. Our results suggest that IQ-SPECT is the optimal technology for myocardial perfusion SPECT imaging

Assessment of left ventricular function by thallium-201 quantitative gated cardiac SPECT

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Baba, Akira; Hano, Takuzo; Ohmori, Hisashi; Ibata, Masayo; Kawabe, Tetsuya; Kubo, Takashi; Kimura, Keizo; Nishio, Ichiro [Wakayama Medical Coll. (Japan)

2002-02-01

Present study was designed to evaluate the accuracy of the measurement of left ventricular volume by quantitative gated SPECT (QGS) software using {sup 201}Tl and the effect of cutoff frequency of Butterworth prereconstruction filter on the calculation of volume. The RH-2 type cardiac phantom and 20 patients with ischemic heart disease were studied. Left ventricular end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) were calculated by the QGS software using the various frequency of Butterworth filter. These parameters were evaluated by Simpson's method using left ventriculography (LVG). The volume of the phantom calculated by QGS was under-estimated by 14%. In the clinical study, EDV and ESV measured by QGS were smaller than those obtained from LVG by 10%. When the cutoff frequency of Butterworth filter was 0.43 cycles/cm, the values measured by QGS were best correlated with those by LVG (EDV: r=0.80, p<0.001; ESV: r=0.86, p<0.001; EF: r=0.80, p<0.001). These data suggest that {sup 201}Tl quantitative gated cardiac SPECT can estimate myocardial ischemia and left ventricular function simultaneously. (author)

Assessment of anatomic relation between pulmonary perfusion and morphology in pulmonary emphysema with breath-hold SPECT-CT fusion images

International Nuclear Information System (INIS)

Suga, Kazuyoshi; Kawakami, Yasuhiko; Iwanaga, Hideyuki; Hayashi, Noriko; Seto, Akiko; Matsunaga, Naofumi

2008-01-01

Anatomic relation between pulmonary perfusion and morphology in pulmonary emphysema was assessed on deep-inspiratory breath-hold (DIBrH) perfusion single-photon emission computed tomography (SPECT)-CT fusion images. Subjects were 38 patients with pulmonary emphysema and 11 non-smoker controls, who successfully underwent DIBrH and non-BrH perfusion SPECT using a dual-headed SPECT system during the period between January 2004 and June 2006. DIBrH SPECT was three-dimensionally co-registered with DIBrH CT to comprehend the relationship between lung perfusion defects and CT low attenuation areas (LAA). By comparing the appearance of lung perfusion on DIBrH with non-BrH SPECT, the correlation with the rate constant for the alveolar-capillary transfer of carbon monoxide (DLCO/VA) was compared between perfusion abnormalities on these SPECTs and LAA on CT. DIBrH SPECT provided fairly uniform perfusion in controls, but significantly enhanced perfusion heterogeneity when compared with non-BrH SPECT in pulmonary emphysema patients (P<0.001). The reliable DIBrH SPECT-CT fusion images confirmed more extended perfusion defects than LAA on CT in majority (73%) of patients. Perfusion abnormalities on DIBrH SPECT were more closely correlated with DLCO/VA than LAA on CT (P<0.05). DIBrH SPECT identifies affected lungs with perfusion abnormality better than does non-BrH SPECT in pulmonary emphysema. DIBrH SPECT-CT fusion images are useful for more accurately localizing affected lungs than morphologic CT alone in this disease. (author)

A novel computer-assisted image analysis of [123I]β-CIT SPECT images improves the diagnostic accuracy of parkinsonian disorders

International Nuclear Information System (INIS)

Goebel, Georg; Seppi, Klaus; Wenning, Gregor K.; Poewe, Werner; Scherfler, Christoph; Donnemiller, Eveline; Warwitz, Boris; Virgolini, Irene

2011-01-01

The purpose of this study was to develop an observer-independent algorithm for the correct classification of dopamine transporter SPECT images as Parkinson's disease (PD), multiple system atrophy parkinson variant (MSA-P), progressive supranuclear palsy (PSP) or normal. A total of 60 subjects with clinically probable PD (n = 15), MSA-P (n = 15) and PSP (n = 15), and 15 age-matched healthy volunteers, were studied with the dopamine transporter ligand [ 123 I]β-CIT. Parametric images of the specific-to-nondisplaceable equilibrium partition coefficient (BP ND ) were generated. Following a voxel-wise ANOVA, cut-off values were calculated from the voxel values of the resulting six post-hoc t-test maps. The percentages of the volume of an individual BP ND image remaining below and above the cut-off values were determined. The higher percentage of image volume from all six cut-off matrices was used to classify an individual's image. For validation, the algorithm was compared to a conventional region of interest analysis. The predictive diagnostic accuracy of the algorithm in the correct assignment of a [ 123 I]β-CIT SPECT image was 83.3% and increased to 93.3% on merging the MSA-P and PSP groups. In contrast the multinomial logistic regression of mean region of interest values of the caudate, putamen and midbrain revealed a diagnostic accuracy of 71.7%. In contrast to a rater-driven approach, this novel method was superior in classifying [ 123 I]β-CIT-SPECT images as one of four diagnostic entities. In combination with the investigator-driven visual assessment of SPECT images, this clinical decision support tool would help to improve the diagnostic yield of [ 123 I]β-CIT SPECT in patients presenting with parkinsonism at their initial visit. (orig.)

A novel computer-assisted image analysis of [123I]β-CIT SPECT images improves the diagnostic accuracy of parkinsonian disorders.

Science.gov (United States)

Goebel, Georg; Seppi, Klaus; Donnemiller, Eveline; Warwitz, Boris; Wenning, Gregor K; Virgolini, Irene; Poewe, Werner; Scherfler, Christoph

2011-04-01

The purpose of this study was to develop an observer-independent algorithm for the correct classification of dopamine transporter SPECT images as Parkinson's disease (PD), multiple system atrophy parkinson variant (MSA-P), progressive supranuclear palsy (PSP) or normal. A total of 60 subjects with clinically probable PD (n = 15), MSA-P (n = 15) and PSP (n = 15), and 15 age-matched healthy volunteers, were studied with the dopamine transporter ligand [(123)I]β-CIT. Parametric images of the specific-to-nondisplaceable equilibrium partition coefficient (BP(ND)) were generated. Following a voxel-wise ANOVA, cut-off values were calculated from the voxel values of the resulting six post-hoc t-test maps. The percentages of the volume of an individual BP(ND) image remaining below and above the cut-off values were determined. The higher percentage of image volume from all six cut-off matrices was used to classify an individual's image. For validation, the algorithm was compared to a conventional region of interest analysis. The predictive diagnostic accuracy of the algorithm in the correct assignment of a [(123)I]β-CIT SPECT image was 83.3% and increased to 93.3% on merging the MSA-P and PSP groups. In contrast the multinomial logistic regression of mean region of interest values of the caudate, putamen and midbrain revealed a diagnostic accuracy of 71.7%. In contrast to a rater-driven approach, this novel method was superior in classifying [(123)I]β-CIT-SPECT images as one of four diagnostic entities. In combination with the investigator-driven visual assessment of SPECT images, this clinical decision support tool would help to improve the diagnostic yield of [(123)I]β-CIT SPECT in patients presenting with parkinsonism at their initial visit.

Clinical application of SPECT in adrenal imaging with iodine-131 6 beta-iodomethyl-19-norcholesterol

Energy Technology Data Exchange (ETDEWEB)

Ishimura, J.; Kawanaka, M.; Fukuchi, M.

1989-04-01

Forty-one patients with or without adrenocortical disorders were studied to evaluate the clinical usefulness of SPECT in adrenal imaging with I-131 Adosterol. In the SPECT images from this study, all glands with either normally functioning or hyperfunctioning adrenal cortices could be detected, while those glands with hypofunctioning adrenal cortices could not be detected. Particularly in transaxial and sagittal slices, the adrenal gland was identified posteriorly and was clearly distinguished from the gallbladder. In preliminary results using SPECT by a standard method, uptake in 68 detectable glands ranged from 1.7% to 4.9% in four glands with Cushing's syndrome, from 1.1% to 1.3% in seven glands with primary aldosteronism, and were distributed below 1.0% in the remaining glands with normally functioning adrenal cortices. These data show that it is possible to evaluate the adrenocortical functioning status simply by analyzing the SPECT images of the adrenal.

Motor activation SPECT for the neurosurgical diseases. Examination protocol and basic study

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Noguchi, Hiroshi; Kawaguchi, Shoichiro; Sakaki, Toshisuke; Imai, Teruhiko; Ohishi, Hajime [Nara Medical Univ., Kashihara (Japan)

1999-07-01

We examined and analyzed the region activated by the unilateral finger opposition task using motor activation single photon emission computed tomography (M-SPECT). M-SPECT studies were carried out on 11 cases, all of whom were normal volunteers (mean age: 49.4 years), none of whom showed any abnormal findings on magnetic resonance images (MRIs) or any neurological abnormalities. The SPECT images for each case were superimposed on the MRIs using Image Fusion Software. The result of the M-SPECT study was expressed as positive or negative. The cases with a marked increase of blood flow in the sensori-motor cortex during the finger opposition task were categorized as positive, and those cases showing no marked increase of blood flow were categorized as negative. Among 11 patients, 10 cases (90.9%) showed positive M-SPECT findings, and the eleventh case showed negative M-SPECT findings. The asymmetry index (AI) was calculated on the sensorio-motor cortex in the SPECT images before and after motor activation, with the 10 cases with positive M-SPECT having an AI before motor activation of 0.99{+-}0.06 (mean{+-}standard deviation) and an AI after motor activation of 1.14{+-}0.07. This change was statistically significant (p<0.05). In the single case categorized as negative, the AI before motor activation was 1.04, and the AI after motor activation was 1.01. There was no significant difference of AI values between the resting and motor activation stages. The positive M-SPECT was seen in 90.9% of the normal volunteer series using a visual inspection method. In these cases, the blood flow in the sensorio-motor cortex significantly increased after application of the finger opposition task using the semi-quantitative method. (author)

Evaluation of the effects of rehabilitation exercise on cerebral infarction with 99Tcm-ECD SPECT brain imaging

International Nuclear Information System (INIS)

Jiang Ningyi; Lu Xianping; Liu Xingguang; Xiao Xiuhong; Xu Jianxing

2003-01-01

Objective: To investigate the therapeutic effects of motor therapy on hemiplegia with SPECT brain perfusion imaging. Methods: The study population consisted of 59 patients with cerebral infarction, and all patients were treated with motor therapy. Among them, 30 cases were assigned to undertake single bridging exercise and 29 cases passive exercise. SPECT brain perfusion imaging was performed before and after motor therapy under the same condition, and the regional cerebral blood flow (rCBF) changes were compared and analysed with visual and semi-quantitative methods; in addition, the relationship between rCBF changes and scores of Fugl-Meyer or Barthel index were also analysed. Results: After motor therapy, various degrees of radioactivity increase were compared with the pretreatment radioactivity hypoperfusion in patients with cerebral infarction, and showed that motor therapy could evidently improve rCBF of regional hypoperfusion. The posttreatment rCBF was higher than the pretreatment level (P<0.01), and the rCBF of group of single bridging was higher than that of passive exercise group. And the changes of rCBF were all significant after motor therapy. In addition, the variation of the rCBF after motor therapy was positively correlated with the variation of Fugl-Meyer and Barthel score. Conclusions: SPECT brain perfusion imaging can serve as a useful method for evaluating the effectiveness of motor therapy in cerebral infarction rehabilitation. The single bridging exercise and the passive exercise are both beneficial to brain rehabilitation, but the former improves the rCBF in lesions better than the later does

Investigation of Collimator Influential Parameter on SPECT Image Quality: a Monte Carlo Study

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Banari Bahnamiri Sh

2015-03-01

Full Text Available Background: Obtaining high quality images in Single Photon Emission Tomography (SPECT device is the most important goal in nuclear medicine. Because if image quality is low, the possibility of making a mistake in diagnosing and treating the patient will rise. Studying effective factors in spatial resolution of imaging systems is thus deemed to be vital. One of the most important factors in SPECT imaging in nuclear medicine is the use of an appropriate collimator for a certain radiopharmaceutical feature in order to create the best image as it can be effective in the quantity of Full Width at Half Maximum (FWHM which is the main parameter in spatial resolution. Method: In this research, the simulation of the detector and collimator of SPECT imaging device, Model HD3 made by Philips Co. and the investigation of important factors on the collimator were carried out using MCNP-4c code. Results: The results of the experimental measurments and simulation calculations revealed a relative difference of less than 5% leading to the confirmation of the accuracy of conducted simulation MCNP code calculation. Conclusion: This is the first essential step in the design and modelling of new collimators used for creating high quality images in nuclear medicine

Feasibility of one-eighth time gated myocardial perfusion SPECT functional imaging using IQ-SPECT

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Caobelli, Federico; Thackeray, James T.; Bengel, Frank M. [Medizinische Hochschule Hannover, Klinik fuer Nuklearmedizin, Hannover (Germany); Soffientini, Alberto; Pizzocaro, Claudio; Guerra, Ugo Paolo [Fondazione Poliambulanza, Department of Nuclear Medicine, Brescia (Italy)

2015-11-15

IQ-SPECT, an add-on to general purpose cameras based on multifocal collimation, can reduce myocardial perfusion imaging (MPI) acquisition times to one-fourth that of standard procedures (to 12 s/view). In a phantom study, a reduction of the acquisition time to one-eighth of the standard time (to 6 s/view) was demonstrated as feasible. It remains unclear whether such a reduction could be extended to clinical practice. Fifty patients with suspected or diagnosed CAD underwent a 2-day stress-rest {sup 99m}Tc-sestamibi MPI protocol. Two consecutive SPECT acquisitions (6 and 12 s/view) were performed. Electrocardiogram-gated images were reconstructed with and without attenuation correction (AC). Polar maps were generated and visually scored by two blinded observers for image quality and perfusion in 17 segments. Global and regional summed stress score (SSS), summed rest score (SRS) and summed difference score (SDS) were determined. Left ventricular volumes and ejection fraction were calculated based on automated contour detection. Image quality was scored higher with the 12 s/view acquisition, both with and without AC. Summed scores were statistically comparable between the 6 s/view and the 12 s/view acquisition, both globally and in individual coronary territories (e.g. in images with AC, SSS were 6.6 ± 8.3 and 6.2 ± 8.2 with 6 s and 12 s/view, respectively, p = 0.10; SRS were 3.9 ± 5.6 and 3.5 ± 5.3, respectively, p = 0.19; and SDS were 2.8 ± 5.7 and 2.6 ± 5.7, respectively, p = 0.59). Both acquisitions allowed MPI-based diagnosis of CAD in 25 of the 50 patients (with AC). Calculated end-diastolic volume (EDV) and end-systolic volume (ESV) were modestly higher with the 6 s/view acquisition than with the 12 s/view acquisition (EDV +4.8 ml at rest and +3.7 ml after stress, p = 0.003; ESV +4.1 ml at rest and +2.6 ml after stress, p = 0.01), whereas the ejection fraction did not differ (-1.2 % at rest, p = 0.20, and -0.9 % after stress, p = 0.27). Image quality and

Towards adapting a normal patient database for SPECT brain perfusion imaging

International Nuclear Information System (INIS)

Smith, N D; Soleimani, M; Mitchell, C N; Holmes, R B; Evans, M J; Cade, S C

2012-01-01

Single-photon emission computerized tomography (SPECT) is a tool which can be used to image perfusion in the brain. Clinicians can use such images to help diagnose dementias such as Alzheimer's disease. Due to the intrinsic stochasticity in the photon imaging system, some form of statistical comparison of an individual image with a 'normal' patient database gives a clinician additional confidence in interpreting the image. Due to the variations between SPECT camera systems, ideally a normal patient database is required for each individual system. However, cost or ethical considerations often prohibit the collection of such a database for each new camera system. Some method of adapting existing normal patient databases to new camera systems would be beneficial. This paper introduces a method which may be regarded as a 'first-pass' attempt based on 2-norm regularization and a codebook of discrete spatially stationary convolutional kernels. Some preliminary illustrative results are presented, together with discussion on limitations and possible improvements

Initial experience with SPECT imaging of the brain using I-123 p-iodoamphetamine in focal epilepsy

International Nuclear Information System (INIS)

La Manna, M.M.; Sussman, N.M.; Harner, R.N.; Kaplan, L.R.; Hershey, B.L.; Bernstein, D.R.; Parker, J.A.; Wolodzko, J.G.; Popky, G.L.

1986-01-01

Twenty-three patients with complex partial seizures refractory to medical treatment were examined with routine electroencephalography (EEG), closed-circuit television EEG (CCTV-EEG), CT and MR imaging, neuropsychological tests, and interictal single photon emission CT with I-123 rho-iodoamphetamine (IMP SPECT). In three patients CT and MR imaging results correlated with the epileptogenic foci as identified on CCTV-EEG. In 21 patients SPECT identified areas of focal reduction in tracer uptake that correlated with the epileptogenic focus identified on CCTV-EEG. In addition, SPECT disclosed other areas of neurologic dysfunction as elicited on neuropsychological tests. Thus, IMP SPECT is a useful tool for localizing epileptogenic foci and their associated dynamic deficits

Automatic lung segmentation in functional SPECT images using active shape models trained on reference lung shapes from CT.

Science.gov (United States)

Cheimariotis, Grigorios-Aris; Al-Mashat, Mariam; Haris, Kostas; Aletras, Anthony H; Jögi, Jonas; Bajc, Marika; Maglaveras, Nicolaos; Heiberg, Einar

2018-02-01

Image segmentation is an essential step in quantifying the extent of reduced or absent lung function. The aim of this study is to develop and validate a new tool for automatic segmentation of lungs in ventilation and perfusion SPECT images and compare automatic and manual SPECT lung segmentations with reference computed tomography (CT) volumes. A total of 77 subjects (69 patients with obstructive lung disease, and 8 subjects without apparent perfusion of ventilation loss) performed low-dose CT followed by ventilation/perfusion (V/P) SPECT examination in a hybrid gamma camera system. In the training phase, lung shapes from the 57 anatomical low-dose CT images were used to construct two active shape models (right lung and left lung) which were then used for image segmentation. The algorithm was validated in 20 patients, comparing its results to reference delineation of corresponding CT images, and by comparing automatic segmentation to manual delineations in SPECT images. The Dice coefficient between automatic SPECT delineations and manual SPECT delineations were 0.83 ± 0.04% for the right and 0.82 ± 0.05% for the left lung. There was statistically significant difference between reference volumes from CT and automatic delineations for the right (R = 0.53, p = 0.02) and left lung (R = 0.69, p automatic quantification of wide range of measurements.

A SPECT study in internal carotid artery occlusion: Discrepancies between flow image and neurologic deficits

International Nuclear Information System (INIS)

Moriwaki, H.; Hougaku, H.; Matsuda, I.; Kusunoki, M.; Shirai, J.

1989-01-01

A SPECT (single photon emission computed tomography) study in internal carotid artery (ICA) occlusion was performed in 6 patients. The validity of iodoamphetamine (IMP) SPECT study in the evaluation of cerebral blood flow (CBF) or neurologic function is still controversial. In this study, the authors showed several cases in whom SPECT images of brain were not compatible with their neurologic deficits. In 2 typical cases, a large low-density area was observed in the non-dominant hemisphere in computed tomography (CT) scan, but no apparent motor-sensory deficits in left limbs were present. In these patients, SPECT study also revealed flow reduction in the affected side of the brain. So there was a possibility that an IMP brain image could not always reflect CBF, which maintains neurologic function of the brain

SPECT Imaging as a Tool for Testing and Challenging Assumptions About Transport in Porous Media

Science.gov (United States)

Moysey, S. M.; DeVol, T. A.; Tornai, M. P.

2014-12-01

Medical imaging has shown promise for unraveling the influence of physical, chemical and biological processes on contaminant transport. Micro-CT scans, for instance, are increasingly utilized to image the pore-scale structure of rocks and soils, which can subsequently be used within modeling studies. A disadvantage of micro-CT, however, is that this imaging modality does not directly detect contaminants. In contrast, Single Photon Emission Computed Tomography (SPECT) can provide the three-dimensional distribution of gamma emitting materials and is thus ideal for imaging the transport of radionuclides. SPECT is of particular interest as a tool for both directly imaging the behavior of long-lived radionuclides of interest, e.g., 99Tc and 137Cs, as well as monitoring shorter-lived isotopes as in-situ tracers of flow and biogeochemical processes. We demonstrate the potential of combining CT and SPECT imaging to improve the mechanistic understanding of flow and transport processes within a heterogeneous porous medium. In the experiment, a column was packed with 0.2mm glass beads with a cylindrical zone of 2mm glass beads embedded near the outlet; this region could be readily identified within the CT images. The column was injected with a pulse of NaCl solution spiked with 99mTcO4- and monitored using SPECT while aliquots of the effluent were used to analyze the breakthrough of both solutes. The breakthrough curves could be approximately replicated by a one-dimensional transport model, but the SPECT data revealed that the tracers migrated around the inclusion of larger beads. Although the zone of large-diameter beads was expected to act as a preferential pathway, the observed behavior could only be replicated in numerical transport simulations if this region was treated as a low-permeability zone relative to the rest of the column. This simple experiment demonstrates the potential of SPECT for investigating flow and transport phenomena within a porous medium.

Evaluation of left ventricular ejection fraction using quantitative gated SPECT (QGS)

International Nuclear Information System (INIS)

Musa, M. A. A.

2010-07-01

Electrocardiographic ally gated myocardial perfusion SPECT (G SPECT) is a state-of the art technique for the combined evaluation of myocardial perfusion and left ventricular function within a single study. It is currently one of the most commonly performed cardiology procedures in a nuclear medicine department. Automation of the image processing and quantification has made this techniques highly reproducible, practical and user friendly in the clinical setting . In patients with coronary artery disease, gating enhances the diagnostic and prognostic capability of myocardial perfusion imaging provides incremental information over the the perfusion data, and has shown potentials for myocardial viability assessment and sequential follow-up after therapy. Evaluation of the left ventricular (L V) function is important in clinical cardiology. Quantifying the degree and extent of the L V functional abnormalities permits a systematic assessment of the disease process on the myocardial performance. The aim of this thesis is to evaluate left ventricular ejection fraction (LVEF) in patients with no evidence of ischemic response during the stress test. This investigation was carried out in view of the few reports concerning the findings ventricular function with gated SPECT in these situations in the normal population, which is relevant when considering the possibility of myocardial stunning. Method: We prospectively studied 30 selected patients, in difference age and gender. A one-day protocol was used, with injection 555 MBq - 1.11 MBq (15 - 30 mCi) of 99 mTc-M1 B1 at stress and rest. Gated perfusion SPECT was acquired 30 to 60 minutes after radiotracer injection in both condition and processed using QGSPECT software. Difference between stress and rest LVEF was calculated. Result and conclusion: rest LVEF was higher in the stress (exercise) group, A trend line was done in both groups and r-value was (0.9) and p=0.04 in acceptance value. Standard deviation of LVEF also was

Study on localization diagnosis with SPECT rCBF image in childhood epilepsy: in comparison with EEG and MRI findings

International Nuclear Information System (INIS)

Wu Meiqian; Tang Jihong; Wu Jinchang; Shi Yizhen

1999-01-01

Objective: To evaluate the diagnostic value of SPECT rCBF imaging in localization of childhood epileptic foci. Methods: rCBF imaging was performed in 74 epileptic patients not in seizure and 10 epileptic patients right in seizure. EEG was performed in 84, MRI in 67 of the subjects mentioned above. All the results of three modalities were compared with each other. Results: The highest positive rate (82.14%) was found in SPECT rCBF imaging, the positive rate in EEG or MRI was 71.43 or 47.76%. The epileptic foci localized by EEG (60 abnormalities) and by MRI (32 abnormalities) were 70.59% or 58.82% in concordance with those by SPECT, respectively. Conclusions: SPECT rCBF imaging is a sensitive and effective method for epileptic foci localization. It may have some advantages over EEG and MRI in detecting and localizing epileptic foci. However, abnormal SPECT areas may cover some abnormalities which do not belong to epileptic category. A combination of these three methods (SPECT, EEG and MRI) will improve the positive rate and accuracy for localizing

Characteristics of images of angiographically proven normal coronary arteries acquired by adenosine-stress thallium-201 myocardial perfusion SPECT/CT-IQ[Symbol: see text]SPECT with CT attenuation correction changed stepwise.

Science.gov (United States)

Takahashi, Teruyuki; Tanaka, Haruki; Kozono, Nami; Tanakamaru, Yoshiki; Idei, Naomi; Ohashi, Norihiko; Ohtsubo, Hideki; Okada, Takenori; Yasunobu, Yuji; Kaseda, Shunichi

2015-04-01

Although several studies have shown the diagnostic and prognostic value of CT-based attenuation correction (AC) of single photon emission computed tomography (SPECT) images for diagnosing coronary artery disease (CAD), this issue remains a matter of debate. To clarify the characteristics of CT-AC SPECT images that might potentially improve diagnostic performance, we analyzed images acquired using adenosine-stress thallium-201 myocardial perfusion SPECT/CT equipped with IQ[Symbol: see text]SPECT (SPECT/CT-IQ[Symbol: see text]SPECT) from patients with angiographically proven normal coronary arteries after changing the CT attenuation correction (CT-AC) in a stepwise manner. We enrolled 72 patients (Male 36, Female 36) with normal coronary arteries according to findings of invasive coronary angiography or CT-angiography within three months after a SPECT/CT study. Projection images were reconstructed at CT-AC values of (-), 40, 60, 80 and 100 % using a CT number conversion program according to our definition and analyzed using polar maps according to sex. CT attenuation corrected segments were located from the mid- and apical-inferior spread through the mid- and apical-septal regions and finally to the basal-anterior and basal- and mid-lateral regions in males, and from the mid-inferior region through the mid-septal and mid-anterior, and mid-lateral regions in females as the CT-AC values increased. Segments with maximal mean counts shifted from the apical-anterior to mid-anterolateral region under both stress and rest conditions in males, whereas such segments shifted from the apical-septal to the mid-anteroseptal region under both stress and rest conditions in females. We clarified which part of the myocardium and to which degree CT-AC affects it in adenosine-stress thallium-201 myocardial perfusion SPECT/CT-IQ[Symbol: see text]SPECT images by changing the CT-AC value stepwise. We also identified sex-specific shifts of segments with maximal mean counts that changed as

New SPECT and PET Radiopharmaceuticals for Imaging Cardiovascular Disease

Directory of Open Access Journals (Sweden)

Oyebola O. Sogbein

2014-01-01

Full Text Available Nuclear cardiology has experienced exponential growth within the past four decades with converging capacity to diagnose and influence management of a variety of cardiovascular diseases. Single photon emission computed tomography (SPECT myocardial perfusion imaging (MPI with technetium-99m radiotracers or thallium-201 has dominated the field; however new hardware and software designs that optimize image quality with reduced radiation exposure are fuelling a resurgence of interest at the preclinical and clinical levels to expand beyond MPI. Other imaging modalities including positron emission tomography (PET and magnetic resonance imaging (MRI continue to emerge as powerful players with an expanded capacity to diagnose a variety of cardiac conditions. At the forefront of this resurgence is the development of novel target vectors based on an enhanced understanding of the underlying pathophysiological process in the subcellular domain. Molecular imaging with novel radiopharmaceuticals engineered to target a specific subcellular process has the capacity to improve diagnostic accuracy and deliver enhanced prognostic information to alter management. This paper, while not comprehensive, will review the recent advancements in radiotracer development for SPECT and PET MPI, autonomic dysfunction, apoptosis, atherosclerotic plaques, metabolism, and viability. The relevant radiochemistry and preclinical and clinical development in addition to molecular imaging with emerging modalities such as cardiac MRI and PET-MR will be discussed.

Clinical application of SPECT and PET in cerebrovascular disease

International Nuclear Information System (INIS)

Ra, Young Shin

2003-01-01

Single photon emission computed tomography(SPECT) and positron emission tomography(PET) are modern imaging techniques that allow for both qualitative are quantitative assessment of hemodynamic changes in cerebrovascular diseases. SPECT has been becoming an indispensable method to investigate regional cerebral blood flow because equipment and isotope are easily available in most general hospitals. Acetazolamide stress SPECT has also been proved to be useful to evaluate the cerebrovascular reserve of occlusive cerebrovascular diseases and to select surgical candidate. PET has gained wide spread clinical use in the evaluation of the hemodynamic and metabolic consequences of extracranial or intracranial arterial obstructive disease despite its complexity and limited availability. PET has been established as an invaluable tool in the pathophysilogy investigation of acute ischemic stroke. The potentials, limitations, and clinical applications of SPECT and PET in various cerebrovascular diseases will be discussed in this article with reviews of literatures

Clinical application of SPECT and PET in cerebrovascular disease

Energy Technology Data Exchange (ETDEWEB)

Ra, Young Shin [Ulsan University College of Medicine, Seoul (Korea, Republic of)

2003-02-01

Single photon emission computed tomography(SPECT) and positron emission tomography(PET) are modern imaging techniques that allow for both qualitative are quantitative assessment of hemodynamic changes in cerebrovascular diseases. SPECT has been becoming an indispensable method to investigate regional cerebral blood flow because equipment and isotope are easily available in most general hospitals. Acetazolamide stress SPECT has also been proved to be useful to evaluate the cerebrovascular reserve of occlusive cerebrovascular diseases and to select surgical candidate. PET has gained wide spread clinical use in the evaluation of the hemodynamic and metabolic consequences of extracranial or intracranial arterial obstructive disease despite its complexity and limited availability. PET has been established as an invaluable tool in the pathophysilogy investigation of acute ischemic stroke. The potentials, limitations, and clinical applications of SPECT and PET in various cerebrovascular diseases will be discussed in this article with reviews of literatures.

The parallel implementation of a backpropagation neural network and its applicability to SPECT image reconstruction

Energy Technology Data Exchange (ETDEWEB)

Kerr, John Patrick [Iowa State Univ., Ames, IA (United States)

1992-01-01

The objective of this study was to determine the feasibility of using an Artificial Neural Network (ANN), in particular a backpropagation ANN, to improve the speed and quality of the reconstruction of three-dimensional SPECT (single photon emission computed tomography) images. In addition, since the processing elements (PE)s in each layer of an ANN are independent of each other, the speed and efficiency of the neural network architecture could be better optimized by implementing the ANN on a massively parallel computer. The specific goals of this research were: to implement a fully interconnected backpropagation neural network on a serial computer and a SIMD parallel computer, to identify any reduction in the time required to train these networks on the parallel machine versus the serial machine, to determine if these neural networks can learn to recognize SPECT data by training them on a section of an actual SPECT image, and to determine from the knowledge obtained in this research if full SPECT image reconstruction by an ANN implemented on a parallel computer is feasible both in time required to train the network, and in quality of the images reconstructed.

A novel computer-assisted image analysis of [{sup 123}I]{beta}-CIT SPECT images improves the diagnostic accuracy of parkinsonian disorders

Energy Technology Data Exchange (ETDEWEB)

Goebel, Georg [Innsbruck Medical University, Department of Medical Statistics, Informatics and Health Economics, Innsbruck (Austria); Seppi, Klaus; Wenning, Gregor K.; Poewe, Werner; Scherfler, Christoph [Innsbruck Medical University, Department of Neurology, Innsbruck (Austria); Donnemiller, Eveline; Warwitz, Boris; Virgolini, Irene [Innsbruck Medical University, Department of Nuclear Medicine, Innsbruck (Austria)

2011-04-15

The purpose of this study was to develop an observer-independent algorithm for the correct classification of dopamine transporter SPECT images as Parkinson's disease (PD), multiple system atrophy parkinson variant (MSA-P), progressive supranuclear palsy (PSP) or normal. A total of 60 subjects with clinically probable PD (n = 15), MSA-P (n = 15) and PSP (n = 15), and 15 age-matched healthy volunteers, were studied with the dopamine transporter ligand [{sup 123}I]{beta}-CIT. Parametric images of the specific-to-nondisplaceable equilibrium partition coefficient (BP{sub ND}) were generated. Following a voxel-wise ANOVA, cut-off values were calculated from the voxel values of the resulting six post-hoc t-test maps. The percentages of the volume of an individual BP{sub ND} image remaining below and above the cut-off values were determined. The higher percentage of image volume from all six cut-off matrices was used to classify an individual's image. For validation, the algorithm was compared to a conventional region of interest analysis. The predictive diagnostic accuracy of the algorithm in the correct assignment of a [{sup 123}I]{beta}-CIT SPECT image was 83.3% and increased to 93.3% on merging the MSA-P and PSP groups. In contrast the multinomial logistic regression of mean region of interest values of the caudate, putamen and midbrain revealed a diagnostic accuracy of 71.7%. In contrast to a rater-driven approach, this novel method was superior in classifying [{sup 123}I]{beta}-CIT-SPECT images as one of four diagnostic entities. In combination with the investigator-driven visual assessment of SPECT images, this clinical decision support tool would help to improve the diagnostic yield of [{sup 123}I]{beta}-CIT SPECT in patients presenting with parkinsonism at their initial visit. (orig.)

Quantitative SPECT reconstruction for brain distribution with a non-uniform attenuation using a regularizing method

International Nuclear Information System (INIS)

Soussaline, F.; Bidaut, L.; Raynaud, C.; Le Coq, G.

1983-06-01

An analytical solution to the SPECT reconstruction problem, where the actual attenuation effect can be included, was developped using a regularizing iterative method (RIM). The potential of this approach in quantitative brain studies when using a tracer for cerebrovascular disorders is now under evaluation. Mathematical simulations for a distributed activity in the brain surrounded by the skull and physical phantom studies were performed, using a rotating camera based SPECT system, allowing the calibration of the system and the evaluation of the adapted method to be used. On the simulation studies, the contrast obtained along a profile, was less than 5%, the standard deviation 8% and the quantitative accuracy 13%, for a uniform emission distribution of mean = 100 per pixel and a double attenuation coefficient of μ = 0.115 cm -1 and 0.5 cm -1 . Clinical data obtained after injection of 123 I (AMPI) were reconstructed using the RIM without and with cerebrovascular diseases or lesion defects. Contour finding techniques were used for the delineation of the brain and the skull, and measured attenuation coefficients were assumed within these two regions. Using volumes of interest, selected on homogeneous regions on an hemisphere and reported symetrically, the statistical uncertainty for 300 K events in the tomogram was found to be 12%, the index of symetry was of 4% for normal distribution. These results suggest that quantitative SPECT reconstruction for brain distribution is feasible, and that combined with an adapted tracer and an adequate model physiopathological parameters could be extracted

Kit formulated asialoglycoprotein receptor targeting tracer based on copolymer for liver SPECT imaging

International Nuclear Information System (INIS)

Liu, Chang; Guo, Zhide; Zhang, Pu; Song, Manli; Zhao, Zuoquan; Wu, Xiaowei; Zhang, Xianzhong

2014-01-01

Introduction: Specific targeting of galactose-carrying molecule to ASGP-R in normal hepatocytes has been demonstrated before. In this study, galactosyl polystyrene was synthesized from controllable ratio of functional monomers and radio-labelled with 99m Tc by formulated kit for SPECT imaging of hepatic function. Methods: p(VLA-co-VNI)(46:54) was synthesized by free-radical copolymerization initiated by AIBN, purified by dialysis, lyophilized to kit with Tricine and TPPTS as co-ligands for 99m Tc labeling. Radiotracer 99m Tc-p(VLA-co-VNI)(46:54)(Tricine)(TPPTS) was prepared and evaluated by in vitro stability, in vivo metabolism, ex vivo biodistribution and microSPECT/CT imaging in normal KM mice. MicroSPECT/CT and microMRI imaging were also performed in C57BL/b6 mice with xenograft hepatic carcinoma for hepatic function evaluation. Results: 99m Tc-p(VLA-co-VNI)(46:54)(Tricine)(TPPTS) was obtained in high radio chemical purity (RCP) (> 99%) by using instant kit without further purification and excellent in vitro and in vivo stability. The result of biodistribution showed that liver had high uptake (90.49 ± 10.68 ID%/g) at 30 min after injection and was blocked significantly by cold copolymer. MicroSPECT imaging in normal KM mice at 1 h and 4 h after injection showed good liver retention and targeting properties. Significant defect of activity was observed in the tumor site which was confirmed by MRI imaging. Conclusion: 99m Tc-p(VLA-co-VNI)(46:54)(Tricine)(TPPTS) with lower ratio of targeting moiety has no observable effect on the specific binding affinity and liver uptake. This makes it possible to introduce more imaging units for multi-modality imaging. Furthermore, the instant kit preparation of 99m Tc-labeling provides great potential for the evaluation of hepatocyte function in clinical application

Neuroradiological findings in primary progressive aphasia: CT, MRI and cerebral perfusion SPECT

International Nuclear Information System (INIS)

Sinnatamby, R.; Antoun, N.A.; Freer, C.E.L.; Miles, K.A.; Hodges, J.R.

1996-01-01

Primary progressive aphasia (PPA) is defined as progressive decline in language for 2 or more years with preservation of activities of daily living and general cognitive functions. Whereas the clinical features of this syndrome have been well documented, the neuroradiological findings have not been studied systematically. We studied 13 patients with PPA retrospectively: 10 underwent CT, 12 MRI and 12 cerebral perfusion studies using 99m Tc-HMPAO SPECT. CT and MR images were scored for focal atrophy by two independent assessors. Initial qualitative assessment of SPECT images was confirmed by quantitative analysis. CY was normal in 5 patients. Focal atrophy, affecting predominantly the left temporal lobe, was seen in 4 of 10 patients on CT, and 10 of 12 on MRI. Atrophy was localised primarily to the superior and middle temporal gyri on MRI. All 12 patients who underwent SPECT had unilateral temporal lobe perfusion defects, in 2 patients of whom MRI was normal. CT is relatively insensitive to focal abnormalities in PPA; MRI and SPECT are the imaging modalities of choice. MRI allows accurate, specific localisation of atrophy with the temporal neocortex. SPECT may reveal a functional decrease in cerebral perfusion prior to establishment of structural change. (orig.)

Neuroradiological findings in primary progressive aphasia: CT, MRI and cerebral perfusion SPECT

Energy Technology Data Exchange (ETDEWEB)

Sinnatamby, R. [Dept. of Radiology, Addenbrooke`s Hospital NHS Trust, Cambridge (United Kingdom); Antoun, N.A. [Dept. of Radiology, Addenbrooke`s Hospital NHS Trust, Cambridge (United Kingdom); Freer, C.E.L. [Dept. of Radiology, Addenbrooke`s Hospital NHS Trust, Cambridge (United Kingdom); Miles, K.A. [Dept. of Nuclear Medicine, Addenbrooke`s Hospital NHS Trust, Cambridge (United Kingdom); Hodges, J.R. [Dept. of Neurology, Addenbrooke`s Hospital NHS Trust, Cambridge (United Kingdom)

1996-04-01

Primary progressive aphasia (PPA) is defined as progressive decline in language for 2 or more years with preservation of activities of daily living and general cognitive functions. Whereas the clinical features of this syndrome have been well documented, the neuroradiological findings have not been studied systematically. We studied 13 patients with PPA retrospectively: 10 underwent CT, 12 MRI and 12 cerebral perfusion studies using {sup 99m}Tc-HMPAO SPECT. CT and MR images were scored for focal atrophy by two independent assessors. Initial qualitative assessment of SPECT images was confirmed by quantitative analysis. CY was normal in 5 patients. Focal atrophy, affecting predominantly the left temporal lobe, was seen in 4 of 10 patients on CT, and 10 of 12 on MRI. Atrophy was localised primarily to the superior and middle temporal gyri on MRI. All 12 patients who underwent SPECT had unilateral temporal lobe perfusion defects, in 2 patients of whom MRI was normal. CT is relatively insensitive to focal abnormalities in PPA; MRI and SPECT are the imaging modalities of choice. MRI allows accurate, specific localisation of atrophy with the temporal neocortex. SPECT may reveal a functional decrease in cerebral perfusion prior to establishment of structural change. (orig.)

Critical myocardial perfusion in hypertrophic cardiomyopathy demonstrated with thallium-201 SPECT with a quantitative bullseye map

International Nuclear Information System (INIS)

Hunter, G.J.

1990-01-01

PURPOSE: A particular problem in hypertrophic cardiomyopathy (HCM) is the need to distinguish between true and apparent ischemia in otherwise normal areas of muscle when these are compared with adjacent hypertrophic muscle. The authors of this paper studied patients with proved HCM to define patterns of perfusion. T1-201 single photon emission CT (SPECT) was performed in 83 HCM patients immediately after stress (dipyridamole, 0.5 mg/kg) and 3 hours later for the redistribution image. The data were analyzed by a normalized quantitative analysis using a local bulls-eye technique. In all patients, the pattern of tracer distribution was different from expected uptake in a normal population. By virtue of the increased microcirculation to hypertrophied muscle, adjacent normal muscle appeared relatively ischemic

Brain SPECT. SPECT in der Gehirndiagnostik

Energy Technology Data Exchange (ETDEWEB)

Feistel, H. (Erlangen-Nuernberg Univ., Erlangen (Germany). Nuklearmedizinische Klinik mit Poliklinik)

1991-12-01

Brain SPECT investigations have gained broad acceptance since the introduction of the lipophilic tracer Tc-99m-HMPAO. Depending on equipment and objectives in different departments, the examinations can be divided into three groups: 1. Under normal conditions and standardised patient preparation the 'rest' SPECT can be performed in every department with a tomographic camera. In cerebrovascular disease there is a demand for determination of either the perfusion reserve in reversible ischemia or prognostic values in completed stroke. In cases of dementia, SPECT may yield useful results according to differential diagnosis. Central cerebral system involvement in immunologic disease may be estimated with higher sensitivity than in conventional brain imaging procedures. In psychiatric diseases there is only a relative indication for brain SPECT, since results during recent years have been contradictory and may be derived only in interventional manner. In brain tumor diagnostics SPECT with Tl-201 possibly permits grading. In inflammatory disease, especially in viral encephalitis, SPECT may be used to obtain early diagnosis. Normal pressure hydrocephalus can be distinguished from other forms of dementia and, consequently, the necessity for shunting surgery can be recognised. 2. In departments equipped for emergency cases an 'acute' SPECT can be performed in illnesses with rapid changing symptoms such as different forms of migraine, transient global amnesia, epileptic seizures (so-called 'ictal SPECT') or urgent forms like trauma. 3. In cooperation with several departments brain SPECT can be practised as an interventional procedure in clinical and in scientific studies. (orig./MG).

Technetium-99m-labelled red blood cell imaging in the diagnosis of hepatic haemangiomas: the role of SPECT/CT with a hybrid camera

Energy Technology Data Exchange (ETDEWEB)

Schillaci, Orazio; Danieli, Roberta; Manni, Carlo; Capoccetti, Francesca; Simonetti, Giovanni [Department of Biopathology and Diagnostic Imaging, University ' ' Tor Vergata' ' , Rome (Italy)

2004-07-01

Delayed liver single-photon emission computed tomography (SPECT) after {sup 99m}Tc red blood cell (RBC) labelling is helpful in detecting hepatic haemangiomas; however, diagnosis can be difficult when lesions are situated adjacent to structures like the inferior vena cava, the heart or hepatic vessels, where blood activity persists. The aims of this study were to evaluate the usefulness of RBC SPECT and transmission computed tomography (RBC SPECT/CT) performed simultaneously with a hybrid imaging system for correct characterisation of hepatic lesions in patients with suspected haemangioma, and to assess the additional value of fused images compared with SPECT alone. Twelve patients with 24 liver lesions were studied. The acquisitions of both anatomical (CT) and functional (SPECT) data were performed during a single session. SPECT images were first interpreted alone and then re-evaluated after adding the transmission anatomical maps. Image fusion was successful in all patients, with perfect correspondence between SPECT and CT data, allowing the precise anatomical localisation of sites of increased blood pool activity. SPECT/CT had a significant impact on results in four patients (33.3%) with four lesions defined as indeterminate on SPECT images, accurately characterising the hot spot foci located near vascular structures. In conclusion, RBC SPECT/CT imaging using this hybrid SPECT/CT system is feasible and useful in the identification or exclusion of suspected hepatic haemangiomas located near regions with high vascular activity. (orig.)

Value of Tc-99m HMPAO SPECT imaging in patients with TIA or acute stroke and normal CT

International Nuclear Information System (INIS)

Koster, K.; Brass, L.M.; Hoffer, P.B.; Gottschalk, A.; Smith, E.O.; Rehm, P.K.

1988-01-01

To determine the value of Tc-99m HMPAO single photon emission CT (SPECT) imaging, 51 patients with transient, acute, or chronic cerebrovascular disease were studied. Seventeen patients presented with recent transient ischemic attack (TIA) or acute stroke and underwent SPECT imaging and CT within 72 hours of presentation. SPECT image interpretation was independent of clinical history and CT findings. Four patients with acute stroke and eight patients with TIA had normal CT findings. All patients with acute stroke (three nonlacunar, one lacunar infarct) and three of eight patients with TIA also showed perfusion abnormalities on Tc-99m HMPAO scans. Thus, Tc-99m HMPAO SPECT may be useful in the early diagnosis and subtype determination of acute stroke and in the evaluation of TIA

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

International Nuclear Information System (INIS)

Sharma, Punit; Kumar, Rakesh; Singh, Harmandeep; Bal, Chandrasekhar; Malhotra, Arun; Julka, Pramod Kumar; Thulkar, Sanjay

2012-01-01

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

Molecular imaging of cancer using PET and SPECT

DEFF Research Database (Denmark)

Kjaer, Andreas

2006-01-01

for molecular imaging of cancer. Especially the possibility of a quick transfer of methods developed in animals to patients (translational research) is an important strength. This article will briefly discuss the newest applications and their importance and perspective in relation to the shift in paradigm......Molecular imaging allows for the study of molecular and cellular events in the living intact organism. The nuclear medicine methodologies of positron emission tomography (PET) and single photon emission computer tomography (SPECT) posses several advantages, which make them particularly suited...

Use of X-ray CT-defined regions of interest for the determination of SPECT recovery coefficients

International Nuclear Information System (INIS)

Tang, H.R.; Brown, J.K.; Hasegawa, B.H.

1996-01-01

For accurate activity per unit volume measurements in SPECT, recovery coefficients are usually applied based on the size and shape of objects being imaged to properly account for the resolution limitations of the gamma camera. Because of noise and limited spatial resolution, determination of object sizes and boundaries can be difficult using the SPECT images alone. We therefore have developed a technique which determines activity concentrations for SPECT using regions of interest (ROI's) obtained from coregistered X-ray CT images. In this study, experimental phantoms containing cylindrical and spherical objects were imaged on a combined X-ray CT/SPECT system and reconstructed data volumes were registered using the known geometry of the system. ROI's were defined on the registered CT images and used to help quantify activity concentration in localized regions and to measure object volumes. We have derived the recovery curves for these objects and scan technique. We have also tested a technique that demonstrates activity quantitation without the need for object and size dependent recovery coefficients in the case of low background

Differential impact of multi-focus fan beam collimation with L-mode and conventional systems on the accuracy of myocardial perfusion imaging: Quantitative evaluation using phantoms

Directory of Open Access Journals (Sweden)

Tatsunori Saho

2013-10-01

Full Text Available Introduction: A novel IQ-SPECTTM method has become widely used in clinical studies. The present study compares the quality of myocardial perfusion images (MPI acquired using the IQ-SPECTTM (IQ-mode,conventional (180° apart: C-mode and L-mode (90° apart: L-mode systems. We assessed spatial resolution, image reproducibility and quantifiability using various physical phantoms. Materials and Methods: SPECT images were acquired using a dual-headed gamma camera with C-mode, L-mode, and IQ-mode acquisition systems from line source, pai and cardiac phantoms containing solutions of 99mTc. The line source phantom was placed in the center of the orbit and at ± 4.0, ± 8.0, ± 12.0, ± 16.0 and ± 20.0 cm off center. We examined quantifiability using the pai phantom comprising six chambers containing 0.0, 0.016, 0.03, 0.045, 0.062, and 0.074 MBq/mLof 99m-Tc and cross-calibrating the SPECT counts. Image resolution and reproducibility were quantified as myocardial wall thickness (MWT and %uptake using polar maps. Results: The full width at half maximum (FWHM of the IQ-mode in the center was increased by 11% as compared with C-mode, and FWHM in the periphery was increased 41% compared with FWHM at the center. Calibrated SPECT counts were essentially the same when quantified using IQ-and C-modes. IQ-SPECT images of MWT were significantly improved (P<0.001 over L-mode, and C-mode SPECT imaging with IQ-mode became increasingly inhomogeneous, both visually and quantitatively (C-mode vs. L-mode, ns; C-mode vs. IQ-mode, P<0.05. Conclusion: Myocardial perfusion images acquired by IQ-SPECT were comparable to those acquired by conventional and L-mode SPECT, but with significantly improved resolution and quality. Our results suggest that IQ-SPECT is the optimal technology for myocardial perfusion SPECT imaging.

A Silicon SPECT System for Molecular Imaging of the Mouse Brain

OpenAIRE

Shokouhi, Sepideh; Fritz, Mark A.; McDonald, Benjamin S.; Durko, Heather L.; Furenlid, Lars R.; Wilson, Donald W.; Peterson, Todd E.

2007-01-01

We previously demonstrated the feasibility of using silicon double-sided strip detectors (DSSDs) for SPECT imaging of the activity distribution of iodine-125 using a 300-micrometer thick detector. Based on this experience, we now have developed fully customized silicon DSSDs and associated readout electronics with the intent of developing a multi-pinhole SPECT system. Each DSSD has a 60.4 mm × 60.4 mm active area and is 1 mm thick. The strip pitch is 59 micrometers, and the readout of the 102...

Clinical applications of SPECT-CT

Energy Technology Data Exchange (ETDEWEB)

Ahmadzadehfar, Hojjat; Biersack, Hans-Juergen (eds.) [University Hospital Bonn (Germany). Dept. of Nuclear Medicine

2014-06-01

Covers the full spectrum of clinical applications of SPECT/CT in diagnosis of benign and malignant diseases. Includes chapters on the use of SPECT/CT for dosimetry and for therapy planning. Completely up to date. Many helpful illustrations. SPECT/CT cameras have considerably improved diagnostic accuracy in recent years. Such cameras allow direct correlation of anatomic and functional information, resulting in better localization and definition of scintigraphic findings. In addition to this anatomic referencing, CT coregistration provides superior quantification of radiotracer uptake based on the attenuation correction capabilities of CT. Useful applications of SPECT/CT have been identified not only in oncology but also in other specialties such as orthopedics and cardiology. This book covers the full spectrum of clinical applications of SPECT/CT in diagnosis and therapy planning of benign and malignant diseases. Opening chapters discuss the technology and physics of SPECT/CT and its use for dosimetry. The role of SPECT/CT in the imaging of a range of pathologic conditions is then addressed in detail. Applications covered include, among others, imaging of the thyroid, bone, and lungs, imaging of neuroendocrine tumors, cardiac scintigraphy, and sentinel node scintigraphy. Individual chapters are also devoted to therapy planning in selective internal radiation therapy of liver tumors and bremsstrahlung SPECT/CT. Readers will find this book to be an essential and up-to-date source of information on this invaluable hybrid imaging technique.

Collimator and energy window optimization for 90Y bremsstrahlung SPECT imaging: A SIMIND Monte Carlo study

International Nuclear Information System (INIS)

Roshan, Hoda Rezaei; Mahmoudian, Babak; Gharepapagh, Esmaeil; Azarm, Ahmadreza; Pirayesh Islamian, Jalil

2016-01-01

Treatment efficacy of radioembolization using Yttrium-90 ( 90 Y) microspheres is assessed by the 90 Y bremsstrahlung single photon emission computed tomography (SPECT) imaging following radioembolization. The radioisotopic image has the potential of providing reliable activity map of 90 Y microspheres distribution. One of the main reasons of the poor image quality in 90 Y bremsstrahlung SPECT imaging is the continuous and broad energy spectrum of the related bremsstrahlung photons. Furthermore, collimator geometry plays an impressive role in the spatial resolution, sensitivity and image contrast. Due to the relatively poor quality of the 90 Y bremsstrahlung SPECT images, we intend to optimize the medium-energy (ME) parallel-hole collimator and energy window. The Siemens e.cam gamma camera equipped with a ME collimator and a voxelized phantom was simulated by the SImulating Medical Imaging Nuclear Detectors (SIMIND) program. We used the SIMIND Monte Carlo program to generate the 90 Y bremsstrahlung SPECT projection of the digital Jaszczak phantom. The phantom consist of the six hot spheres ranging from 9.5 to 31.8 mm in diameter, which are used to evaluate the image contrast. In order to assess the effect of the energy window on the image contrast, three energy windows ranging from 60 to 160 KeV, 160 to 400 KeV, and 60 to 400 KeV were set on a 90 Y bremsstrahlung spectrum. As well, the effect of the hole diameter of a ME collimator on the image contrast and bremsstrahlung spectrum were investigated. For the fixed collimator and septa thickness values (3.28 cm and 1.14 mm, respectively), a hole diameter range (2.35–3.3 mm) was chosen based on the appropriate balance between the spatial resolution and sensitivity. The optimal energy window for 90 Y bremsstrahlung SPECT imaging was extended energy window from 60 to 400 KeV. Besides, The optimal value of the hole diameter of ME collimator was obtained 3.3 mm. Geometry of the ME parallel-hole collimator and energy