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Sample records for tl-201 emission computed

  1. The dobutamine stress Tl-201 myocardial single photon emission computed tomography for coronary artery stenosis caused by Kawasaki disease

    International Nuclear Information System (INIS)

    Karasawa, Kensuke; Ayusawa, Mamoru; Noto, Nobutaka; Yamaguchi, Hideo; Okada, Tomoo; Harada, Kensuke

    1994-01-01

    Noninvasive cardiac imaging with pharmacologic stress Tl-201 single photon emission computed tomography (SPECT) as an alternative to exercise test is now getting popular for patients with Kawasaki disease. Dobutamine infusion produces hemodynamic change which is quite similar to exercise induced hemodynamic change. Material consisted of 17 patients (13 males, 4 females) with coronary occlusion or significant coronary stenosis (≥75% diameter stenosis) caused by Kawasaki disease. After step-wise infusion of dobutamine up to 40 μg/kg/min., quantitative analysis of Tl-201 SPECT was obtained. No patient had a symptomatic arrhythmia or severely stress-induced ischemia. The sensitivity and specificity of dobutamine induced perfusion defects were 65% (11 to 17) and 92% (1 of 13) respectively. The sensitivity was 87% (7 of 8) in patients with the left coronary artery lesions and 46% (6 of 13) in patients with the right coronary artery lesions. We conclude that a quantitative analysis of Tl-201 SPECT after step-wise infusion of dobutamine is a safe and clinically useful method for detection of stress-induced myocardial ischemia in coronary artery stenosis caused by Kawasaki disease. (author)

  2. Reproducibility and quantitativity of oblique-angle reconstruction in single photon emission computed tomography using Tl-201 myocardial phantom

    International Nuclear Information System (INIS)

    Bunko, Hisashi; Nanbu, Ichiro; Seki, Hiroyasu

    1984-01-01

    This study was carried out in order to evaluate reproducibility and quantitativity of oblique-angle reconstruction of myocardial phantom SPECT. Myocardial phantom with transmural and subendcardial defects, and off-axis phantom with wall thickness changing continuously from 0 to 23 mm were used. Sixty projection data in every 6 0 were aquired using dual-camera (ZLC) with high resolution collimators connected to Scintipac-2400 computer system. Oblique-angle reconstructed images were obtained by indicating the long axis of the phantom manually in the transaxial and vertical long axial tomograms. Reproducibility and quantitativity were evaluated by creating circumferential profile (CFP) of the finally reconstructed short axial images. Inter- and intra-operater reproducibility of relative counting ratio were less than 6.7% (C.V.) and 3.3% (C.V.), respectively. Both inter- and intraoperater reproducibility of absolute counts were better than that of counting ratio (less than 5.1% (C.V.) and 2.9% (C.V.), respectively). Variation of defect location in the reconstructed image and between the slices were less than 1 sampling interval of CFP (6 0 ) and 0.6 slice, respectively. Quantitativity of counts in the reconstructed images was poor in the transmulal defect, but was fair in the subendocardial defect. Counting ratio was greatly affected by wall thickness. Temporal quantitatibity or linearity of the counts in sequential SPECTs was good in non-defect area, especially when wall thickness was greater than 70% (16 mm) of maximum. In conclusion, three-dimensional oblique-angle reconstruction in Tl-201 myocardial SPECT could be applicable to relative and temporal quantitation of local myocardial activity other than defect area for the quantitative evaluation of Tl-201 myocardial wash-out. (J.P.N.)

  3. Studies on Tl-201 single photon emission computed tomography (SPECT) of myocardium in patients with ischemic heart disease

    International Nuclear Information System (INIS)

    Igarashi, Takeki; Yokoi, Toshio; Ueda, Mitsuru; Horimoto, Masashi; Funayama, Naoki; Takenaka, Takashi; Tasho, Teruo; Tsutsuji, Yuko; Oi, Tsuyoshi

    1985-01-01

    Seventy-six patients with IHD were divided into 2 groups, A) angina pectoris (n=50) and B) previous myocardial infarction(n=26). Each group was classified into three subgroups, without considering hypertension, that is 1) without complication, 2) with hypercholesterolemia, and 3) with diabetes mellitus. We studied and compared the findings of ECG, Echocardiogram (ECHO) and Emission CT (ECT) in these patients at rest. In the previous myocardial infarction group (Group B), we could find 100% ischemic patterns on ECG, 100% asynergy of either IVS or the posterior wall on ECHO and higher percentages of various grade of perfusion defects on ECT compared with group A. In group A, the percentages of perfusion defects were similar in three subgroups. But interestingly, in the hypercholesterolemic group, we could find diffuse moth-eaten like low perfusion areas on ECT. Further study is required whether this finding is peculiar for angina pectoris with hypercholesterolemia or an artifact on ECT. The percentage of ischemic patterns on ECG was lower than in the other groups. In angina pectoris with diabetes mellitus, asynergy in ECHO finding was a significantly higher percentage, compared with other groups. We believe, that ECG, ECHO and ECT are of compensatory importance in the diagnosis of patients with IHD. (author)

  4. Brain SPECT with Tl-201 DDC

    International Nuclear Information System (INIS)

    Bruine, J.F. de.

    1988-01-01

    The development, animal and human experiments and the first clinical results of a new blood flow tracer thallium-201 diethyldithiocarbamate (Tl-201 DDC) are discussed for functional brain imaging with single-photon emission computed tomography (SPECT). 325 refs.; 43 figs.; 22 tabs

  5. Tl-201 and Tc-99m-DTPA neuro-SPECT in cerebral radiation necrosis

    International Nuclear Information System (INIS)

    Cleto, E.M. Jr.; Holmes, R.A.; Gumerlock, M.K.; Cabeen, M.; Logan, K.W.; Hoffman, T.J.

    1992-01-01

    The results in 3 cases of radiation necrosis demonstrate that by using both radionuclides Tl-201 and Tc-99m-DTPA, one can provide a semi-quantitative method to differentiate recurrent tumor from radiation necrosis. Focally increased cerebral Tl-201 activity in irradiated brain tumor patients is not specific for tumor recurrence, but when used in combination with DTPA, one is able to estimate the amount of Tl-201 activity resulting from increased blood-brain barrier permeability. If the average Tl-201 index is less than the average Tc-99m-DTPA index it suggests that the increased Tl-201 activity results primarily from blood-brain barrier breakdown. Tc-99m-DTPA SPECT, in addition to Tl-201 SPECT, or serial Tl-201 SPECT imaging may increase the accuracy of brain scintigraphy in differentiating radiation necrosis from tumor recurrence. To verify these preliminary findings, we are in the process of analyzing additional SPECT data on 9 more patients with malignant brain tumors. Using a slightly different method of quantifying Tl- 201/Tc-99m-DTPA ratios (computing the ratio of intralesional Tl-201 or Tc-99m-DTPA activity compared to adjacent scalp activity), patients with tumor recurrence have higher Tl-201/Tc-99m-DTPA ratios compared to those with radiation necrosis (verbal communication with Dr. Mary K. Gumerlock). (orig.) [de

  6. Quantitative interpretation of myocardial Tl-201 single-photon emission computerized tomograms: A probabilistic approach to the assessment of coronary artery disease

    International Nuclear Information System (INIS)

    Maddahi, J.; Prigent, F.; Staniloff, H.; Garcia, E.; Becerra, A.; Van Train, K.; Swan, H.J.C.; Waxman, A.; Berman, D.

    1985-01-01

    Probabilistic criteria for abnormality would enhance application of stress-redistribution Tl-201 rotational tomography (tomo) for evaluation of coronary artery disease (CAD). Thus, 91 pts were studied, of whom 45 had angiographic CAD (≥ 50% coronary narrowing) and 46 were normal (nl). The validity of this model was prospectively tested in the remaining 51 pts (26 nls and 25 with CAD) by comparing the predicted and observed likelihood of CAD in four subgroups (I-IV). In this paper a logistic model is developed and validated that assigns a CAD likelihood to the quantified size of tomograhic myocardial perfusion defects

  7. Coronary flow reserve index corrected by exercise load using Tl-201 SPECT

    International Nuclear Information System (INIS)

    Kubota, Yasushi; Sugihara, Hiroki; Azuma, Akihiro

    1990-01-01

    For simple, non-invasive evaluation of coronary flow reserve during exercise, we investigated the coronary flow reserve index using the ratio of change of fractional distribution in the regional myocardium to oxygen demand. The subjects included 24 patients with effort angina pectoris and 11 normal volunteers. PTCA was peformed for 11 patients. Using the biological properties of Tl-201 single photon emission computed tomography (SPECT) was performed at submaximal exercise and at rest by two successive injections of Tl-201 within a short time interval (double dose method). The correlation between the fractional distribution in the myocardium (Δ-Fract) and the oxygen demand during exercise and at rest were evaluated. Δ-Fract correlated well with the rate of change of the pressure rate product (Δ-PRP), and Δ-Fract/Δ-PRP (CRI) was a good indicator of the coronary flow reserve index. CRI in the ischemic region correlated well with the percent area stenosis of the supplying coronary artery and improved with resolution of percent area stenosis of the target coronary artery after PTCA, but in some cases they were not above the normal range. CRI as obtained by exercise SPECT using the double dose method is useful for non-invasively estimating the coronary flow reserve during exercise, and it can be used for evaluating the effect before and after PTCA. (author)

  8. Tl-201 per rectum scintigraphy in chronic liver disease: assessment of Tl-201 uptake indices

    International Nuclear Information System (INIS)

    Moon, Won Jin; Choi, Yun Young; Cho, Suk Shin; Lee, Min Ho

    1999-01-01

    Heart to liver ratio on Tl-201 per rectal scintigraphy (shunt index) is known to be useful in the assessment of portal systemic shunt. We assessed Tl-201 uptake pattern and early liver/heart uptake rate of Tl-201 and correlated with shunt index in patients with chronic active hepatitis (CAH) and liver cirrhosis (LC). Fifty eight patients with biopsy-proven chronic liver disease (35 with CAH, 23 with LC) underwent Tl-201 per rectum scintigraphy after instillation of 18.5 MBq of Tl-201 into the upper rectum. We evaluated hepatic uptake (type 1: homogeneous, 2: inhomogeneous segmental, 3: inhomogeneous nonsegmental) and extrahepatic uptake of spleen, heart and kidney (grade 0: no uptake, 1: less than liver, 2: equal to liver, 3: greater than liver). We measured the early liver/heart uptake rate (the slope of the liver to heart uptake ratio for 10 mim) and shunt index (heart to liver uptake ratio). Tl-201 uptake pattern and early liver/heart uptake rate of Tl-201 was correlated with the pathologic diagnosis and shunt index. Hepatic uptake patterns of type 1 and 2 were dominant in CAH (CAH: 27/35, LC: 8/23), and type 3 in LC (CAH: 8/35, LC: 15/23)(p<0.005). The grades of extrahepatic uptake were higher in LC than in CAH (spleen: p<0.001, other soft tissue: p<0.005). The early liver/heart uptake rate of CAH (0.110±0.111) was significantly higher than that of LC (0.014±0.090)(p<0.001). The sensitivity and specificity of the early liver/heart uptake rate were 77.7% and 67.7% in differentiating LC from CAH. There was negative correlation between early liver/heart uptake rate and shunt index (r=-0.3347, p<0.01). Hepatic and extrahepatic uptake pattern and early liver/heart uptake rate on Tl-201 per rectum scintigraphy are useful in the assessment of portal systemic shunt in patients with chronic liver disease

  9. Clinical evaluation of Tl-201 SPECT in nasopharyngeal carcinoma

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    Togawa, Takashi; Yui, Nobuharu; Shimada, Fumiyuki; Omura, Ken; Katahashi, Tatsuaki; Hatano, Kazuo [Chiba Cancer Center (Japan). Hospital

    1995-03-01

    Tl-201 SPECT was performed on 19 patients, 13 males and 6 females aged 28 to 73 yrs (mean 51), with nasopharyngeal carcinoma (NPC) histologically proven to evaluate whether or not Tl-201 SPECT was useful and reliable for assessing the tumor viability of NPC. Thirty eight Tl-201 SPECT studies were performed for the follow-up study after radiation therapy in 9 of 19 patients and for the assessment of tumor extent before treatment in the other 10 patients. Data acquisition was started 5 min after the intravenous injection of 111 MBq of Tl-201 chloride using a three-head rotating gamma camera (Toshiba GCA 9300A) equipped with fan-beam collimators. Tl-201 clearly accumulated to the tumor in 10 patients before radiation treatment and increased Tl-201 uptake by the lesion disappeared after the treatment. Three of 9 patients who were followed up after radiotherapy developed apparent local recurrence and Tl-201 SPECT could definitely visualize these recurrent lesions. Tl-201 SPECT was very useful for detecting local recurrent tumor. High resolution SPECT system with the use of Tl-201 chloride is a new reliable and accurate diagnostic tool for assessing the tumor viability of NPC. (author).

  10. Tl-201 SPECT in nasopharyngeal carcinoma for monitoring treatment response

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    Togawa, Takashi; Yui, Nobuharu; Hatano, Kazuo; Sekiya, Yuichi; Shimada, Fumiyuki; Omura, Ken; Takeuchi, Yosuke [Chiba Cancer Center Hospital (Japan); Katahashi, Tatsuaki

    1996-03-01

    A total of 43 Tl-201 SPECT studies were performed on 11 patients with nasopharyngeal carcinoma (NPC) histologically proven before and after treatment to evaluate whether or not Tl-201 SPECT was a useful diagnostic tool for assessing tumor viability. Data acquisition was started 5 min after the intravenous injection of 111 MBq of Tl-201 chloride using 3-head rotating gamma camera SPECT systems (GCA-9300A). Three patients received radiotherapy alone and the other 8 received radiotherapy and chemotherapy. Treatment response was classified as complete response (CR), partial response (PR), and no change (NC) based on the findings of MRI. Intense Tl-201 uptake by the tumor was seen in all patients before treatment. After treatment, MRI showed 1 CR and 10 PR patients, whereas Tl-201 uptake was decreased in 4 and disappeared in 7 patients. Follow-up MRI and Tl-201 SPECT studies of 4 PR patients revealed that tumor gradually decreased after the desappearance of Tl-201 uptake. Tl-201 SPECT was a very useful tool for monitoring radiotherapeutic effects. (author).

  11. Coronary collateral circulation during exercise assessed with stress Tl-201 SPECT

    International Nuclear Information System (INIS)

    Tanaka, Takeshi; Aizawa, Tadanori

    1995-01-01

    Stree Tl-201 single photon emission computed tomography (SPECT) was undertaken in 25 patients with complete occlusion of the left anterior descending artery in which the major collateral circulation was septal segment supplied by the right posterior descending artery with no significant occlusion. The ratio of blood flow in ischemic area to that in normal area was quantitatively determined on Tl-201 images, and the degree of ischemia was expressed by Tl uptake ratio. Ischemia was found in 22 of the 25 patients. Of the 22 patients, 9 showed Tl uptake ratio of less than 50%. Tl uptake ratio in the inferior segment was 76.8±10.3%. In 11 patients, it was less than 75%. Redistribution images were acquired in 19 patients. Changes in Tl uptake ratio on the 90 degrees projection of the septum were less than 20%, with a lowest value of 59.1±11.3% in 14 patients; and these were 20% or more, with a lowest value of 45.2±11.1% in 8 patients. When coronary collateral circulation is not supplied by exercise, septal perfusion may be decreased. In cases of complete occlusion of the anteiror descending artery, ischemia may not uniform over the whole ischemic area and may be noticeable around the anterior descending artery. In cases of lesions in the anteior descending artery, however, collateral circulation supplied by the right coronary artery may occur by exercise when ischemia in the anterior segment was severer than in the septal segment. (N.K.)

  12. Evaluation of Tl-201 lung uptake and impairment of pulmonary perfusion on scintigraphies in pulmonary tuberculosis

    International Nuclear Information System (INIS)

    Fujii, Tadashige; Tanaka, Masao; Koizumi, Tomonori; Kubo, Keishi

    2000-01-01

    Tl-201 lung uptake in 74 patients (85 lesions) and pulmonary perfusion in 105 patients were studied to evaluate clinical usefulness of Tl-201 lung uptake and perfusion lung scintigraphy in pulmonary tuberculosis, using a scintillation camera with a mini-computer system. As indices of Tl-201 lung uptake, lung (lesion) to upper mediastinum uptake ratio (L/M) and visual grading were used. L/M in pulmonary tuberculosis was 1.96±0.66, which was significantly larger than 1.04±0.24 in healthy controls and lower than that in heart diseases with left heart failure and idiopathic interstitial pneumonia, and showed no significant differences with that in acute pneumonia, pyothorax, primary lung cancer and malignant mediastinal tumor. L/M in pulmonary tuberculosis did not correlate with CRP, erythrocyte sedimentation rate, Gaffky number of sputum and body temperature. It correlated with the type of pulmonary tuberculosis according to the Gakken Classification reflecting the disease activity. It was larger in the exudative type, caseo-infiltrative one, disseminated one, one with cavity in infiltrative lesion than the fibro-caseous one. On perfusion lung scintigram, impairment of pulmonary perfusion larger than area of the entire unilateral lung was observed in 68 cases (64.8%). Area of hypoperfused lung field, which correlated with % vital capacity (r=0.60, p=0.0002) and PaO 2 (r=0.39,p=0.0024), was significantly larger in patients with silicosis and those with bilateral pleural involvements such as pleural callosity than in those with type III according to the Gakkai Classification. Most of the patients showed decreased pulmonary perfusion and Tl-201 accumulation of which grade reflects the disease activity in active tuberculous lesion. Patients with miliary tuberculosis and those with silicotuberculosis showed diffuse Tl-201 accumulation in the both lungs. Tl-201 lung scintigraphy seems to be useful for visualizing active tuberculous lesions, particularly the ones that

  13. Evaluation of myocardial and skeletal muscular involvement with thallium-201 myocardial emission computed tomography and whole body scintigraphy

    International Nuclear Information System (INIS)

    Yamamoto, Shuhei; Matsushima, Hideo; Sotobata, Iwao; Suzuki, Akio; Indo, Toshikatsu; Matsuoka, Yukihiko

    1986-01-01

    Thallium-201 (Tl-201) myocardial emission computed tomography and whole body scintigraphy were performed using a rotating gamma camera in 64 patients with neurologic disease and 14 normal subjects. Thallium-201 myocardial perfusion defects were seen in 40 % of the muscular involvement in 47 patients with muscular dystrophy (MD), in whom morphological abnormality of the heart was common. There was strong relationship between the degree of left ventricular perfusion defects and the degree of pulmonary uptake of Tl-201. Thallium-201 whole body scintigraphy showed homogeneous distribution of Tl-201 in the extremities in normal subjects, and perfusion defects in 73 % of the muscular lesions in MD patients. Muscular and skeletal lesions for MD appear to progress independently. Thallium-201 imaging seems to be of clinical value in assessing the muscular and skeletal lesions. (Namekawa, K.)

  14. Detection of extracardiac disease during Tl-201 myocardial perfusion study

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    Park, Chan H.; Lee, Myoung Hoon; Yoon, Seok Nam; Hwang, Kyung Hoon [College of Medicine, Ajou Univ., Suwon (Korea, Republic of)

    2001-07-01

    It is important to observe extracardiac disease processes (ECD) during cardiac perfusion imaging for valuable information can be obtained at no extracost to patients. The aim of the study is to find out the frequency of ECD during Tl-201 stress myocardial perfusion imaging (TSMPI). Retrospective evaluation of 552 TSMPI was done. There were 229 males and 223 females reffered for evaluation of possible ischemic heart disease. Their ages range from 20 to 80 with mean age of 58.8 years. Three mCi (111 MBq) of 201 TlCl is used for adenosine or treadmil exercise testing and myocardial SPECT is performed utilizing low energy high resolution collimators and a triple-head camera ( MultiSPECT, Siemens medical systems, Inc., Hoffman Estate, III., USA). In addition to routine cardiac Tl-201 SPECT acquisition, included in the protocol is 1 min, anterior planar views in 128 128 matrix after stress and rest SPECT studies for evaluation of lung uptake and chamber size. Utilizing these views ECD is assessed. Five patients had focal increased activity suggesting tumor and 3 of 5 cases were confirmed as malignancy. The malignancies were thyroid cancer (Hurthle cell), lung cancer, and breast cancer. Benign lesions were autonomous thyroid nodule and pheochromocytoma. Other ECDs include pericardial effusion, pleural effusion, and paralyzed hemidiapharm.. Extracardiac disease processes such as benign or malignancy are easily detected during Tl-201 myocardial perfusion imaging using our acquisition protocol at no cost to the patients. This information could be life saving in some patients for early detection of clinically unsuspected malignancy.

  15. Bio-sorption of Tl-201 radionuclide on olive pomace

    International Nuclear Information System (INIS)

    Yapici, Sinan; Eroglu, Hayrettin; Varoglu, Erhan

    2011-01-01

    This work presents an investigation on the bio-sorption of Tl-201 radionuclide used in nuclear medicine on olive pomace. The experimental parameters were chosen as temperature, the initial pH of the solution, stirring speed, bio-sorbent dose and nominal particle size of bio-sorbent. The initial pH of the solution was found to be the most effective parameter. Thermodynamic analysis gave negative values for ΔG and ΔH. The kinetics of the bio-sorption process fitted very well to the pseudo-second order rate model.

  16. Evaluation of Tl-201 SPECT imaging findings in prostate cancer

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    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.

  17. Visualization of nasopharyngeal carcinoma with Tl-201 chloride and a three-head rotating gamma camera SPECT system

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    Togawa, Takashi; Yui, Nobuharu; Kinoshita, Fujimi; Shimada, Fumiyuki; Omura, Ken; Takemiya, Sanzou (Chiba Cancer Center Hospital (Japan))

    1993-05-01

    Tl-201 SPECT was performed on 12 patients with nasopharyngeal carcinoma (NPC) by means of a three-head rotating gamma camera to evaluate whether or not Tl-201 SEPCT was useful and reliable for assessing the tumor viability of NPC. Tl-201 clearly accumulated in the tumor in 3 patients before radiation treatment and increased Tl-201 uptake by the lesion ceased after the treatment. Three of 9 patients who were followed up after radiotherapy developed apparent local recurrence and Tl-201 SPECT clearly visualized these recurrent lesions. Tl-201 SPECT was very useful for assessing the tumor response to irradiation and for detecting local recurrent tumor. A high resolution SPECT system employing Tl-201 chloride is a new reliable and accurate diagnostic tool for the assessment of NPC. (author).

  18. Critical review-current status of Tl-201 myocardial scintigraphy in patients with ischemic heart disease

    International Nuclear Information System (INIS)

    Kanemoto, Nariaki; Hoer, G.

    1982-01-01

    Thallium-201 myocardial scintigraphy (TMS) is the most important, accurate and noninvasive diagnostic tool for the detection of regional myocardial perfusion. This agent is a potassium analog and the biologic half life in normal myocardium is 4 hours. Therefore, serial imaging after a single dose of Tl-201 at the peak of the exercise makes differential diagnosis possible between stress induced ischemia (transient perfusion defect with redistribution) and myocardial fibrosis or scar (permanent defect). The reproducibility is around 90%. The overall sensitivity in 4,094 patients reviewed from the literature was 83% with a specificity of 87%. The accuracy of TMS for the diagnosis of ischemic heart disease was 85%. Sensitivity increases in the order of visual (83%), computer analysis of standard scintigraphy (91%), and computer analysis of pinhole tomography (96%), but there is no significant difference in specificity among them. Also, sensitivity increases in the order of single (73%), double (83%) and triple (90%) vessel d isease. However, TMS does not indicate the correct number of vessels involved. In this paper, we discuss the current status of use and limitations of TMS in the diagnosis of ischemic heart disease. (author)

  19. A new method for crosstalk correction in simultaneous dual-isotope myocardial imaging with Tl-201 and I-123

    International Nuclear Information System (INIS)

    Tsuji, Akinori; Kojima, Akihiro; Oyama, Yoichi; Tomiguchi, Seiji; Kira, Tomohiro; Takagi, Yoshikazu; Shimomura, Osamu; Takahashi, Mutsumasa; Matsumoto, Masanori

    1999-01-01

    We have developed a new method of crosstalk correction in simultaneous dual-isotope imaging with Tl-201 and I-123 by using crosstalk ratios and a blurring filter. Single isotope myocardial studies (10 for Tl-201 and 7 for I-123) were performed with a dual energy window acquisition mode and two low energy general-purpose collimators. Then two planar images acquired with dual energy windows for a Tl-201 line source and an I-123 line source were obtained to measure line spread functions (LSFs) and crosstalk ratios for each image. The line source experiments showed that the LSFs for the Tl-201 imaging window from the single Tl-201 source were very similar to those for the I-123 imaging window from the single Tl-201 source, but the LSFs for the Tl-201 imaging window from the single I-123 source had broad shapes which differed from those for the I-123 imaging window from the single I-123. To obtain accurate I-123 crosstalk images in the Tl-201 imaging window from the I-123 images in the I-123 imaging window, we designed a low-pass blurring filter. In 7 clinical I-123 MIBG studies, I-123 window images processed with this filter became very similar to the Tl-201 window image from the single I-123 source. The method proposed in this study can accurately correct the crosstalk in dual isotope studies with Tl-201 and I-123 and is easily applicable to conventional gamma camera systems with any dual energy window acquisition mode. (author)

  20. On clinical usefulness of Tl-201 scintigraphy for the management of malignant soft tissue tumors

    International Nuclear Information System (INIS)

    Terui, Shoji; Terauchi, Takashi; Abe, Hiroyuki; Fukuma, Hisatoshi; Beppu, Yasuo; Chuman, Koichi; Yokoyama, Ryohei

    1994-01-01

    The purpose of this study was to investigate Tl-201 as a tumor scanning agent in patients with malignant soft tissue sarcomas and to establish the sensitivity of this type of scintigraphy concerning local recurrences or metastases that may remain clinically suspected. Seventy-eight patients with malignant soft tissue sarcomas and 22 with benign soft tissue tumors were studied. Of these 78 malignant soft tissue sarcomas patients, the sensitivity of Tl-201 (81.2%) was higher than that of Ga-67 (68.8%). Thirty-three out of 78 patients received a total of 95 consecutive scintigraphic follow-up examinations. Therapeutic effects was assessed by comparing the results of Tl-201 examinations with the clinical findings. Of these 33 patients, the therapeutic effects observed were as follows: complete remission 1, partial remission 8, progress of disease 1, and no remarkable change 23. Tl-201 scintigraphy has proved itself very useful not only in clinically detecting the malignant soft tissue sarcomas and in assessing therapeutic effects on these diseases, but also in assessing the follow-up patients with malignant soft tissue sarcomas. (author)

  1. Right ventricular visualization by Tl-201 myocardial scintigraphy in chronic obstructive pulmonary disease

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    Fujii, Tadashige; Tanaka, Masao; Takeda, Masashi; Matsuzawa, Yukinori; Handa, Kenjiro; Yoshimura, Kazuhiko (Shinshu Univ., Matsumoto, Nagano (Japan). Faculty of Medicine)

    1993-04-01

    Tl-201 myocardial scintigraphy was performed in 130 patients with chronic obstructive pulmonary disease (COPD) to evaluate right ventricular hypertrophy, and the clinical significance of this method was studied. Tl-201 uptake ratios of the right ventricle, which represents the ratio of total counts of the right ventricle to counts of the administered dose of Tl-201, was higher in COPD, especially in pulmonary emphysema and B type COPD by Burrows classification than in controls. The grade of visualization of the right ventricle by visual assessment (RVV) was marked (+++) in only a few cases and moderate (++) in many cases (more than 80%) in all diseases except bronchial asthma. The incidence of right ventricular hypertrophy by electrocardiogram, right-sided heart failure and marked dyspnea (Hugh-Jones 4[center dot]5) were very low in cases with RVV grade ++ and very high in cases with +++. The grade of RVV was related to the severity of pulmonary perfusion impairment, although in diffuse panbronchiolitis the RVV was relatively slight compared with the impairment of perfusion. May parameters of pulmonary function such as %VC, FEV1.0%, RV/TLC, V25, %DLCO, Raw, [Delta]N[sub 2] and PaO[sub 2] showed abnormal values in patients with RVV grade of (++) or (+++) in all diseases except bronchial asthma. In COPD, Tl-201 myocardial scintigraphy seems to be useful for assessment of right ventricular overloading, and for follow-up observation and differentiation between cor pulmonale and right ventricular hypertrophy secondary to cardiac diseases by observing Tl-201 uptake of the lung and left ventricle. (author).

  2. Right ventricular visualization by Tl-201 myocardial scintigraphy in chronic obstructive pulmonary disease

    International Nuclear Information System (INIS)

    Fujii, Tadashige; Tanaka, Masao; Takeda, Masashi; Matsuzawa, Yukinori; Handa, Kenjiro; Yoshimura, Kazuhiko

    1993-01-01

    Tl-201 myocardial scintigraphy was performed in 130 patients with chronic obstructive pulmonary disease (COPD) to evaluate right ventricular hypertrophy, and the clinical significance of this method was studied. Tl-201 uptake ratios of the right ventricle, which represents the ratio of total counts of the right ventricle to counts of the administered dose of Tl-201, was higher in COPD, especially in pulmonary emphysema and B type COPD by Burrows classification than in controls. The grade of visualization of the right ventricle by visual assessment (RVV) was marked (+++) in only a few cases and moderate (++) in many cases (more than 80%) in all diseases except bronchial asthma. The incidence of right ventricular hypertrophy by electrocardiogram, right-sided heart failure and marked dyspnea (Hugh-Jones 4·5) were very low in cases with RVV grade ++ and very high in cases with +++. The grade of RVV was related to the severity of pulmonary perfusion impairment, although in diffuse panbronchiolitis the RVV was relatively slight compared with the impairment of perfusion. May parameters of pulmonary function such as %VC, FEV1.0%, RV/TLC, V25, %DLCO, Raw, ΔN 2 and PaO 2 showed abnormal values in patients with RVV grade of (++) or (+++) in all diseases except bronchial asthma. In COPD, Tl-201 myocardial scintigraphy seems to be useful for assessment of right ventricular overloading, and for follow-up observation and differentiation between cor pulmonale and right ventricular hypertrophy secondary to cardiac diseases by observing Tl-201 uptake of the lung and left ventricle. (author)

  3. In vivo effects of radioactive properties of Tl-201 on human carbonic anhydrase activity

    Science.gov (United States)

    Sahin, Ali; Senturk, Murat

    2017-04-01

    Carbonic anhydrase (CA) is a family of metalloenzymes that requires Zn as a cofactor and catalyze the quick conversion of CO2 to HCO3- and H+. Inhibitors of the carbonic anhydrases (CAs) have medical usage of significant diseases such as glaucoma, epilepsy, gastroduodenal ulcers, acid-base disequilibria and neurological disorders. The most useful radioisotope, Tl-201, decays by electron capture, emitting Hg X-rays ( 70-80 keV), and photons of 135 and 167 keV in 10% total abundance. Therefore, it has good imaging characteristics without excessive patient radiation dose. It is the most popular isotope used for thallium 201 nuclear cardiac stress tests. In the present study, In vivo inhibitory effect of Tl-201 (Thallium-201) on human erythrocyte carbonic anhydrase (CA) activity were investigated.

  4. Volumetric index of Tl-201 uptake in symptomatic patients after high - dose radiation treatment for high-grade gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, P.A.; Garada, B.M.; Loeffler, J.S. [Brigham and Womens Hospital, Boston, MA (United States)]|[Harvard Medical School, Boston, MA (United States)] [and others

    1995-05-01

    To verify the utility of a volumetric estimation of Tl-201 uptake in the context of possible astrocytoma recurrence after surgery, radiotherapy plus stereotactic boost (radiosurgery/brachitherapy), we analyzed sequential Tl-201/Tc99m-HMPAO brain SPECT studies of 28 patients (18 m/10 f). These were categorized as having tumor mass recurrence (TM), infiltrating tumor cells but no definite tumor mass (IT), or radiation changes and necrosis (RCN) after stereotactic biopsy and/or craniotomy. SPECT studies were obtained with a high-resolution dedicated gamma camera (CERASPECT, Digital Scinitgraphics, Inc.) and image acquisition was performed after intravenous Tl-201 (18.5 MBq) and Tc-99m HMPAO (740 MBq). In order to include relevant information about tumor burden, a volumetric index of Tl-201 uptake was expressed in cm{sup 3} related to voxel size (4.6 x 10{sup -3} cc) within an elliptical ROI that included the tumor area. Only voxels with a threshold {ge} 2 in relation to the average scalp Tl-201 uptake were included and this total number of voxels expressed in cc was compared to previously established maximal tumor/scalp Tl-201 uptake ratios (T/S) and histopathology. Results are presented as the median (min-max) and differences were considered significant for p<0.05. Differences were significant between all groups for both ratios and volume indices and correlation between the two variables was 0.90. In conclusion, the volumetric index of Tl-201 is similar to the maximal Tl-201 T/S ratios in discriminating tumor recurrence and radiation necrosis, suggesting a future role for the volumetric index estimation in the evaluation of treatment efficacy and patient follow-up.

  5. Simultaneous Tc-99m/Tl-201 imaging using energy-based estimation of the spatial distributions of contaminant photons

    International Nuclear Information System (INIS)

    Moore, S.C.; Tow, D.E.; English, R.J.; Syravanh, C.; Zimmerman, R.E.; Chan, K.H.; Kijewski, M.F.; Brigham and Women's Hospital, Boston, MA

    1995-01-01

    The advantages of simultaneous acquisition of TC-99m and Tl-201 myocardial perfusion SPECT images can be fully realized only if the effects of the Tc-99m agent can be accurately removed from the Tl-201 image. The authors and others have previously reported simultaneous dual-isotope techniques for cardiac studies which make use of a third energy-window to estimate the Tc-99m scatter to be subtracted from the Tl-201 window. The authors have recently demonstrated, however, using a Monte Carlo program which simulates all details of the photon transport, that lead x-rays produced in the collimator may also contribute significantly to contamination in the Tl-201 window. The spatial distribution of the Tc-99m scattered photons differs from that of the lead x-rays. Therefore, the authors modified their correction technique so that, at each projection angle, the contaminant image to be subtracted from the image in the Tl-201 window was estimated as a linear combination of a scatter-window (90--110 keV) image, blurred by a 2D Gaussian filter, and the Tc-99m photopeak image, blurred by a different Gaussian filter. For simulated data which included 'liver' activity and non-uniform 'lung' attenuation, the improved dual-window subtraction technique provided a more accurate estimate of the true Tl-201 image, with less image noise, than did the single-window correction

  6. Evaluation of cardiomyopathy in Duchenne muscular dystrophy by Tl-201 myocardial SPECT

    International Nuclear Information System (INIS)

    Jinnouchi, Seishi; Asai, Junko; Inoue, Kenjirou; Hoshi, Hiroaki; Watanabe, Katsushi.

    1985-01-01

    Clinical evaluation of Tl-201 myocardial SPECT in patients with cardiomyopathy of Duchenne type progressive muscular dystrophy (DMD) was reported. Cases subjected to study were 14 DMD and 8 normal. Using a rotating gamma camera system (ZLC7500 and Scintipac 70A), SPECT data were collected for 16 minutes (32 angles x 30 sec/angle, 180 0 ). The hypoperfusion areas of the left ventricular muscle were observed in 10 patients (71 %), which was in posterior wall (71 %), inferior wall (57 %), lateral and anterior wall (43 %) in the order of frequency. The hypoperfusion area became wider with age and stage, exept for some patients. It was suggested that myocardial degeneration in DMD started in posterior wall and then spread in other areas. For the purpose of quantitative evaluation of myocardial damage, Tl-201 myocardial uptake ratio (MUR) and left ventricular muscle volume (LVMV) were calculated using the results obtained by phantom studies. MUR and LVMV were higher in DMD than those of normal individuals (3.6 +- 1.0 %: 2.7 +- 0.3 %, p < 0.05, 190.2 +- 67.5 ml: 157.8 +- 21.5 ml, n.s., respectively). (author)

  7. Exercise Tl-201 myocardial scintigraphy and coronary blood flow velocity in patients with hypertrophic cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Sugihara, Hiroki; Umamoto, Ikuo; Harada, Yoshiaki (Kyoto Prefectural Univ. of Medicine (Japan)) (and others)

    1992-03-01

    In 22 patients with hypertrophic cardiomyopathy not associated with coronary stenosis, findings of exercise Tl-201 myocardial scintigraphy were reviewed in relation to coronary blood flow velocity. Blood flow velocity of the left antero-inferior segment was recorded by using a Doppler catheter. From time velocity integration in systolic and diastolic phases, both % systolic fraction (%SF) and %diastolic 1st third fraction (%d1F) were obtained. A decreased perfusion was visually assessed on exercise Tl-201 myocardial images. In addition, transient dilation of the left ventricular cavity was quantitatively assessed by expressing it as a transient dilation index (TDI) for subendocardial ischemia. Coronary blood flow velocity was characterized by a decrease in both %SF and %d1F and negative systolic flow. Both %SF and %d1F were inversely correlated with TDI. Coronary negative systolic flow was frequently associated with a decreased perfusion. These results suggest factors such as left ventricular relaxation impairment, other than coronary small vessel lesions, may also be involved in the occurrence of myocardial ischemia in hypertrophic cardiomyopathy. (N.K.).

  8. The reverse redistribution phenomenon with Tl-201: Coronary angiographic and clinical correlation

    International Nuclear Information System (INIS)

    Silberstein, E.B.; DeVries, D.F.

    1984-01-01

    Poor perfusion with Tl-201 in a myocardial segment at rest with apparently normal distribution immediately post-exercise, (reverse redistribution, RR) has been correlated with a high probability of coronary artery disease (CAD) in two previous studies of 20 and of 5 patients. In 785 consecutive Tl-201 exercise studies over a 15 month period the authors re-examined the clinical and coronary angiographic correlates of this finding. RR was read on 38 studies (5%) and of these, 20 patients had coronary angiograms. Of these 20, 9 (5 male, 4 female) had coronary arteries with <50% stenosis but three of these 9 had other diseases involving the heart (idiopathic cardiomyopathy, 2: familial Mediterranean fever). Six of these false positives with RR had no defect immediately post stress, while three also had perfusion defects post stress which improved. Of the 11 true positives with abnormal angiography and RR, 4 had only RR while 7 had RR plus other post stress defects. Contrary to prior reports, in only 7 of the 11 was the vessel supplying the area of RR the least obstructed coronary artery. RR therefore had a positive predictive value for C.A.D. 11/20 = 55%, also contrary to prior reports. For all heart disease the predictive value rises to 14/20 = 70%

  9. Tl-201 myocardial SPECT in patients with Duchenne's muscular dystrophy: A long-term follow-up

    International Nuclear Information System (INIS)

    Nagamachi, S.; Jinnouchi, S.; Ono, S.; Hoshi, H.; Inoue, K.; Watanabe, K.

    1989-01-01

    Tl-201 SPECT was used to evaluate myocardial involvement in 13 patients with Duchenne's muscular dystrophy. Serial studies of 9 patients were done at two-year intervals. The hypoperfused areas of the left ventricle became more prominent with age and severity

  10. Tl-201 Gated-SPECT: Post-exercise regional myocardial dysfunction in normoperfused territories as an indicator of TVD

    International Nuclear Information System (INIS)

    Bharathi Dasan, J.; Choudhury, S.; Hadi, M.; Kumar, R.; Malhotra, A.; Karthikeyan, G.

    2002-01-01

    Introduction: The identification of multivessel coronary artery disease has implications in management of patients with coronary artery disease (CAD). Non-gated Thallium-201 SPECT has a suboptimal sensitivity in the detection of individual coronary stenoses in patients with multi-vessel disease. The present study assesses the incremental value of regional post-stress myocardial dysfunction obtained with Thallium-201 gated SPECT studies (Tl-201gSPECT), in the detection of individual coronary stenoses in patients with triple-vessel coronary artery disease (TVD). Materials and Methods: Patients in group I, n= 25 (24 males, 1 female), aged 36 to 75 years (avg-56 + 9.3 yrs), with previously diagnosed or subsequently proven angiographic evidence of TVD, underwent same day exercise stress and redistribution myocardial Tl-201 gSPECT studies. An additional 15 patients (13 males, 2 females), aged 41 to 75 (avg. 58 + 9), who were angiographically normal (n=3) or had SVD (n=7) or DVD (n=5) were also recruited under the same protocol (group II). All patients underwent symptom limited treadmill exercise with the same protocol. The mean double product in group I was 22,985 + 4280 and the reasons for termination of exercise were THR in 14, dyspnoea in 7, fatigue in 2, ischemic ST segment changes in 1 and angina in 1. In group II, the mean double product was 24000 + 4326 and the reasons for termination of exercise were THR in 11, fatigue in 2, and chest pain in 1. The anterior and inferior myocardial walls were each divided into 3 segments, the septum and lateral wall into 6 and apex into 2. Segmental perfusion (SP), walls thickening (WT) and wall motion (WM) were then assessed. SP was scored from 0=normal to 4= absent. Emory Cardiac Toolbox software generated polar maps were used to score WT. WM was assessed qualitatively using scores of 0=normal to 4= dyskinesia. Where the endocardial border was not visualized, computer generated endocardial outlines were used to assess the wall

  11. A case of thymoma misdiagnosed ad parathyroid adenoma on Tc-99m pertechnetate/Tl-201 subtraction scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Yong An; Yoo, Ie Ryung; Kim, Sung Hoon; Chung, Soo Kyo; Wang, Young Pil; Jung, Ji Han; Lee, Kyo Young; Kim, Byung Kee [The Catholic University of Korea, Seoul (Korea, Republic of)

    2001-08-01

    A large superior mediastinal mass was found incidentally by ultrasonography in a 60-year-old man. There was an abnormal accumulation of 71-201 in the lower pole of left thyroid gland, extending into left superior mediastinum on Tc-99m pertechnetate/Tl-201 subtraction scan. Laboratory findings relating thyroid and parathyroid were all within normal range. We considered the mass as a non-functioning parathyroid adenoma tentatively. However, subsequent surgery and pathologic examination revealed the mass to be a benign mixed thymoma. We report a case of patient with thymoma showing unusual Tc-99m pertechnetate/Tl-201 subtraction imaging and laboratory findings, and suggest to consider the possibility of other mediastinal tumors rather than parathyroid adenoma.

  12. Left ventricular ejection fraction determined by gated Tl-201 perfusion SPECT and quantitative software

    International Nuclear Information System (INIS)

    Hyun, In Young; Kim, Sung Eun; Seo, Jeong Kee; Hong, Eui Soo; Kwan, Jun; Park, Keum Soo; Lee, Woo Hyung

    2000-01-01

    We compared estimates of ejection fraction (EF) determined by gated Tl-201 perfusion SPECT (g-Tl-SPECT) with those by gated blood pool (GBP) scan. Eighteen subjects underwent g-Tl-SPECT and GBP scan. After reconstruction of g-Tl-SPECT, we measured EF with Cedars software. The comparison of the EF with g-Tl-SPECT and GBP scan was assessed by correlation analysis and Bland Altman plot. The estimates of EF were significantly different (p<0.05) with g-Tl-SPECT (40%±14%) and GBP scan (43%±14%). There was an excellent correlation of EF between g-Tl-SPECT and GBP scan (r=3D0.94, p<0.001). The mean difference of EF between GBP scan and g-Tl-SPECT was +3.2%. Ninety-five percent limits of agreement were ±9.8%. EF between g-Tl-SPECT and GBP scan were in poor agreement. The estimates of EF by g-Tl-SPECT was well correlated with those by GBP scan. However, EF of g-Tl-SPECT doesn't agree with EF of GBP scan. EF of g-Tl-SPECT can't be used interchangeably with EF of GBP scan.=20

  13. Effect of cardiac drugs on imaging studies with thallous chloride Tl 201

    Energy Technology Data Exchange (ETDEWEB)

    Waschek, J.; Hinkle, G.; Basmadjian, G.; Allen, E.W.; Ice, R.

    1981-11-01

    The effects of commonly used cardiac drugs on cardiac imaging with thallium-201-labeled thallous chloride were studied. This retrospective study included 62 men ranging in age from 37 to 70 years who had cardiac imaging attempted with thallium during an eight-month period. Seven drugs were being used by at least eight patients each--propranolol, nitroglycerin ointment, isosorbide dinitrate, digoxin, hydrochlorothiazide, potassium chloride, and quinidine. Myocardial-to-background (M/Bk) ratios were calculated for each patient. No drug consistently affected the M/Bk ratios. The lowest M/Bk ratio was found in patients receiving digoxin, but there was no significant difference between the M/Bk ratios for patients taking digoxin (1.38 +/- 0.16) and those not taking digoxin (1.45 +/- 0.10) (0.05 less than p less than 0.10, Student's t test). It is concluded that the drugs studied do not affect cardiac imaging with thallous chloride Tl 201.

  14. Predictive values of early rest/24 hour delay Tl-201 perfusion SPECT for wall motion improvement in patients with acute myocardial infarction after reperfusion

    International Nuclear Information System (INIS)

    Hyun, In Young; Kwan, June

    1998-01-01

    We studied early rest/24 hour delay Tl-201 perfusion SPECT for prediction of wall motion improvement after reperfusion in patients with acute myocardial infarction. Among 17 patients (male/female=11/6, age: 59±13) with acute myocardial infarction, 15 patients were treated with percutaneous transcoronary angioplasty (direct:2, delay:11) and intravenous urokinase (2). Spontaneous resolution occurred in infarct related arteries of 2 patients. We confirmed TIMI 3 flow of infarct-related artery after reperfusion in all patients with coronary angiography. We performed rest Tl-201 perfusion SPECT less then 6 hours after reperfusion and delay Tl-201 perfusion SPECT next day. Tl-201 uptake was visually graded as 4 point score from normal (0) to severe defect (3). Rest Tl-201 uptake ≤2 or combination of rest Tl-201 uptake ≤2 or late reversibility were considered to be viable. Myocardial wall motion was graded as 5 point score from normal (1) to dyskinesia (5). Myocardial wall motion was considered to be improved when a segment showed an improvement ≥1 grade in follow up echo compared with the baseline values. Among 98 segments with wall motion abnormality, the severity of myocardial wall motion decrease was as follow: mild hypokinesia: 18/98 (18%), severe hypokinesia: 28/98 (29%), akinesia: 51/98 (52%), dyskinesia: 1/98 (1%). The wall motion improved in 85%. Redistribution (13%), and reverse redistribution (4%) were observed in 24 hour delay SPECT. Positive predictive value (PPV) and negative predictive value (NPV) of combination of late reversibility and rest Tl-201uptake were 99%, and 54%.PPV and NPV of rest Tl-201 uptake were 100% and 52% respectively. Predictive values of comibination of rest Tl-201 uptake and late reversibility were not significantly different compared with predictive values of rest Tl-201 uptake only. We conclude that early Tl-201 perfusion SPECT predict myocardial wall motion improvement with excellent positive but relatively low negative

  15. Clinical usefulness of technetium-99m pyrophosphate and Tl-201 myocardial imaging for the estimation of myocardial infarction

    International Nuclear Information System (INIS)

    Suzuki, Akio; Sato, Akihiko; Miyakoda, Hiroyuki; Watanabe, Toshiya; Itatsu, Hidetaka; Ueda, Osamu; Sakurai, Kuniteru; Kawai, Naoki; Sotobata, Iwao.

    1985-01-01

    A correlative study was performed between the infarct size estimated by either technetium-99 pyrophosphate (Tc-PYP) or Tl-201 myocardial imaging, and the cumulative total creatinine phosphokinase activity (ΣCPK) or left ventricular ejection fraction (LVEF) in 40 patients with acute myocardial infarction. Tc-PYP infarct area (TcIA) and mean Tl-201 uptake ratio (MUR) were calculated as indices of myocardial infarct size. LVEF was evaluated by first pass method using Tc-PYP in the acute phase of myocardial infraction. In 23 patients with anterior myocardial infarction, a significant correlation was shown between either TcIA or anterior-wall MUR and ΣCPK (r=0.81 and r=-0.69, respectively) and also between either TcIA or anterior-wall MUR and LVEF (r=-0.84 and r=0.80, respectively). In 17 patients with inferior myocardial infarction without additional involvement of right ventricular wall, inferior-wall MUR correlated with ΣCPK (r=-0.74). No statically significant correlation was shown between TcIA and ΣCPK, and also between either TcIA or inferior-wall MUR and LVEF. In conclusion, the infarct size estimated with Tc-PYP or Tl-201 myocardial imaging could be a useful clinical indicator of the severity of acute myocardial infarction especially in anterior wall. (author)

  16. Effects of exercise on kinetics and distribution K-43 and Tl-201 in isolated myocardium: concise communication

    International Nuclear Information System (INIS)

    Llaurado, J.G.; Smith, G.A.; Madden, J.A.

    1981-01-01

    Kinetics and distribution K-43 and Tl-201 were studied in isolated myocardial tissue from rats to assess the effects of exercise. Rats in some groups were forced to swim for 2 h; immediately after swimming, they were injected with 0.2 mCi of 43 KCl or 201 TlCl; at 0.5 or 3 hr after injection they were killed and a myocardial segment was obtained and subjected to washout with nonradioactive Krebs fluid in a special chamber. In control groups (rested) the exercise was omitted. A three-comparatment model (extracellular, main intracellular, and subcellular) was used; transport rate constants and relative compartment sizes were determined. The most striking finding was the unchangeability of K-43 parameters with regard to experimental condition. On the other hand, Tl-201 parameters were modified by exercise and sampling time. Notable differences between K-43 and Tl-201 kinetics were found. The hypothesis that alterations at the cellular level may affect regional myocardial distribution of a radionuclide is discussed

  17. Both semiquantitative degree of rest Tl-201 uptake and reversibility at 24 hour-delay were needed to predict wall motion improvement after bypass surgery

    International Nuclear Information System (INIS)

    Lee, D. S.; Yoon, S. N.; Kim, K. B.; Jeong, Z. K.; Lee, M. C.; Ko, C. S.

    1997-01-01

    Controversy still exists about how to use the uptake at rest and 24 hour delay in rest redistribution Tl-201 SPECT to predict improvement of wall motion abnormality after bypass surgery. To find the best way to combine diagnostic efficacy of Tl-201 SPECT to predict myocardial viability, we studied the predictive values (positive: PPV, negative: NPV) of rest and 24 hour-delay Tl-201 SPECT in 21 patients. Wall motion was assessed comparing preoperative post-stress gated Tc-99m-MIBI SPECT with that of 3 months after surgery. Four point scoring system was used for 17 myocardial segments to asses uptakes ( 0 to 3 for normal to defect) at rest and 24 hour-delay and wall motion ( 0 to 3 for normal to dyskinesia). Ejection fraction improved after surgery (5011% vs 4313%). Intra-observer and inter-observer reproducibility of EF was 7 and 9% respectively when we used 3D Perfusion-Motion Map. Sixty seven segments showed wall motion abnormality before surgery. Predictive values of rest Tl-201 uptake decrease were as follows: 0: 15/15(100%), 1: 30/34(88%), 2: 6/11 (55%), 3: 3/7(43%). So PPV of mild decrease was 88%, and NPV of severe decrease was 50%. Delayed reversibility was evaluated in 37 segments (15 patients). Twenty seven segment had persistence or aggravation, but the other 10 segments improved at 24 hour delay. PPV of reversible 10 segments was 80%, and NPV of reversibility was only 46%. PPV of combination of rest Tl-201 uptake of mild degree and 24 hour reversibility was 86% (38/44) and NPV of neither one was 88%. We concluded that both semi-quantitative degree of Tl-201 uptake at rest and reversibility at 24 hour delay was the best to warrant or abandon postoperative improvement of abnormal wall motion found at preoperative post-stress gated myocardial SPECT

  18. Evaluation of Cadmium-Zinc-Telluride Detector-based Single-Photon Emission Computed Tomography for Nuclear Cardiology: a Comparison with Conventional Anger Single-Photon Emission Computed Tomography.

    Science.gov (United States)

    Niimi, Takanaga; Nanasato, Mamoru; Sugimoto, Mitsuo; Maeda, Hisatoshi

    2017-12-01

    The differences in performance between the cadmium-zinc-telluride (CZT) camera or collimation systems and conventional Anger single-photon emission computed tomography (A-SPECT) remain insufficient from the viewpoint of the user. We evaluated the performance of the D-SPECT (Spectrum Dynamics, Israel) system to provide more information to the cardiologist or radiological technologist about its use in the clinical field. This study evaluated the performance of the D-SPECT system in terms of energy resolution, detector sensitivity, spatial resolution, modulation transfer function (MTF), and collimator resolution in comparison with that of A-SPECT (Bright-View, Philips, Japan). Energy resolution and detector sensitivity were measured for Tc-99m, I-123, and Tl-201. The SPECT images produced by both systems were evaluated visually using the anthropomorphic torso phantom. The energy resolution of D-SPECT with Tc-99m and I-123 was approximately two times higher than that of A-SPECT. The detector sensitivity of D-SPECT was higher than that of A-SPECT (Tc-99m: 4.2 times, I-123: 2.2 times, and Tl-201: 5.9 times). The mean spatial resolution of D-SPECT was two times higher than that of A-SPECT. The MTF of D-SPECT was superior to that of the A-SPECT system for all frequencies. The collimator resolution of D-SPECT was lower than that of A-SPECT; however, the D-SPECT images clearly indicated better spatial resolution than the A-SPECT images. The energy resolution, detector sensitivity, spatial resolution, and MTF of D-SPECT were superior to those of A-SPECT. Although the collimator resolution was lower than that of A-SPECT, the D-SPECT images were clearly of better quality.

  19. Evaluation of latent cardiac disease in diabetic patients with Tl-201 exercise myocardial scintigram and blood pool scintigram

    International Nuclear Information System (INIS)

    Miyashita, Takeo; Kasai, Ryutaro; Ikebe, Nobuhiko; Nagai, Yoshikazu; Yamasawa, Ikuhiro; Ibukiyama, Chiharu; Notoya, Yoko

    1990-01-01

    To find latent heart disease in diabetic patients, 142 diabetic patients were divided into 4 groups: (1) no hypertension and normal ECG (DM group); (2) hypertension recognized clinically (HT group); (3) myocardial damage on ECG (MD group); (4) group associated with the previous 2 (HT+MD group). In all groups Tl-201 exercise myocardial scintigrams and blood pool scintigrams were taken for comparative analysis. Positive rates of SPECT were 27.7% (23/83) in the DM group, 30.0% (9/30) in the HT group, 50.0% (6/12) in the MD group, and 70.6% (12/17) in the HT+MD group. The rate in the HT+MD group was significantly higher than in that of the DM and HT groups (p<0.001, p<0.01). Blood pool scintigrams revealed that in the HT+MD group, as compared with the normal control group, both 1/3 FF and PFR were significantly depressed, in addition to significant TPF prolongation in the former (p<0.001, p<0.05, p<0.05). These findings suggest that in diabetic patients hypertension and myocardial damage would lead to a high incidence of abnormality in SPECT and left ventricular rapid filling dysfunction. This indicate a high incidence of latent cardiac disease which can be recognized in diabetic patients by stress myocardial and blood pool scintigrams. (author)

  20. Evaluation of the effect of reconstructed image pixel size on defect detectability in Tl-201 fan-beam SPECT by an observer performance study

    Science.gov (United States)

    Gregoriou, G. K.; Gsui, B. M. W.; Gullberg, G. T.

    1995-08-01

    The effect of reconstructed image pixel size in the fan-beam filtered backprojection method in myocardial defect detection was investigated using an observer performance study and receiver operating characteristics (ROC) analysis. A mathematical phantom of the human torso was used to model the anatomy and Thallium-201 (Tl-201) uptake in humans. Realistic projections from the phantom were simulated using a low-energy high resolution fan-beam collimator that incorporated the effects of photon attenuation, spatially varying detector response, scatter, and Poison noise. For a fan-beam collimator with a focal length of 55 cm and with a radius of rotation of 25 cm, the magnification at the center of rotation was two and the maximum magnification in the reconstructed region of interest was three. Myocardial defects were simulated as Gaussian-shaped decreases in Tl-201 uptake distribution. By changing the reconstructed image pixel size, five different classes of reconstructed images resulted, with projection bin width to reconstructed image pixel size (PBIP) ratios of 1, 2, 3, 4, and 5. The results from the observer study indicate that the reconstructed image pixel size has a significant effect on myocardial defect detection in reconstructed Tl-201 SPECT images. Moreover, the study indicated that in order to ensure maximum defect detectability the PBIP ratio should be at least as large as the maximum possible magnification within the reconstructed image array.

  1. Comparison of Exercise Tc-99m Tetrofosmin Myocardial Perfusion SPECT with Exercise Tl-201 Myocardial Perfusion SPECT in the diagnosis of coronary artery disease in patients with left bundle branch block (LBBB)

    International Nuclear Information System (INIS)

    Kumar, R.; Barai, S.; Malhotra, A.; Karthikeyan, G.; Mishra, S.; Sood, A.K.

    2004-01-01

    Exercise Tl-201 Myocardial Perfusion SPECT (MPS) has poor specificity for the diagnosis of coronary artery disease (CAD) in patients with left bundle branch block (LBBB). Tc-99m-Tetrofosmin is an agent with kinetics similar to Sestamibi. There has not been any study reported in literature comparing exercise Tc-99m Tetrofosmin MPS with that of exercise Tl-201 MPS in patients with LBBB. We compared exercise Tc-99m-Tetrofosmin MPS with exercise Tl-201 MPS in the diagnosis of coronary artery disease (CAD) in patients with LBBB. Exercise Tc-99m Tetrofosmin and Tl-201 myocardial SPECT studies were conducted in 15 patients with LBBB suspected to have CAD. All patients underwent coronary angiography. Both tests were assessed for their ability to differentiate normally perfused coronary artery territories from those supplied by a diseased coronary artery, with special reference to the septum. Tc-99m Tetrofosmin MPS identified 13 out of 15 segments perfused by a stenosed coronary artery as compared to 14 by Tl-201 SPECT. Tc99m-Tetrofosmin and Tl-201 MPS studies revealed perfusion abnormalities in 15 and 16 of 40 normal segments respectively. False positive perfusion defects over the septum identified on the stress thallium scans did not show reversibility in the rest images. There was no difference in the reversibility of the true and false positive segments identified on the Tetrofosmin scans. The results of this study showed comparable efficacy of exercise Tc-99m Tetrofosmin MPS and Tl-201 MPS in the diagnosis of CAD in patients with LBBB. (author)

  2. The causes and clinical significance of exercise-induced silent myocardial ischemia evaluated by ischemic range and intensity with exercise Tl-201 myocardial SPECT

    International Nuclear Information System (INIS)

    Moriai, Naoki; Nakai, Kenji; Hiramori, Katsuhiko

    1992-01-01

    We investigated the causes and long-term prognosis of exercise-induced silent myocardial ischemia (SMI) by means of exercise Tl-201 myocardial SPECT (Ex-SPECT) in 97 patients with effort angina or old myocardial infarction (OMI). These patients were proven to have significant stenosis by coronary angiography. The subjects were divided into three groups based on the presence or absence of Tl-201 redistribution (RD) or angina during exercise testing. Group one consisted of 34 patients who had RD on Ex-SPECT and angina during exercise testing: the painful myocardial ischemia (PMI) group. The second group consisted of 38 patients who had RD on Ex-SPECT, but no angina during exercise testing: the SMI group. The third group consisted of 25 patients who had no RD: the RD (-) group. The ischemic range and intensity were quantified by the defect volume ratio (DVR) and defect severity index (DSI), respectively. Comparison of the DVR and DSI values for the PMI and SMI groups revealed that the DVR and DSI values for the SMI group were lower than those of the PMI group. Also the prognosis of the SMI group tended to be worse than that of the RD (-) group. Thus, we concluded that the SMI and PMI groups should receive identical treatment. (author)

  3. The diagnostic value of Tc-99m PYP, Tl-201 dual isotope SPECT to predict the viability of damaged myocardium in the acute phase of myocardial infarction

    International Nuclear Information System (INIS)

    Matsuo, Hitoshi; Watanabe, Sachiro; Arai, Masazumi

    1991-01-01

    To assess the diagnostic value of Tc-99m pyrophosphate (PYP), Tl-201 dual isotope SPECT for the evaluation of myocardial viability, segmental comparison between dual isotope SPECT and exercise, delayed, and reinjected Tl study were performed with 18 acute myocardial infarction (AMI) patients. Among 72 damaged myocardial segments, 48 segments (67%) were judged as viable by chronic phase Tl studies. The segments with severely reduced Tl uptake by dual SPECT showed significantly lower prevalence of viable myocardium than the segments with reduced and normal Tl uptake (p<0.001). The segments with PYP accumulation localized to the subendocardium represented the favorable outcome compared with the transmural accumulation (p<0.001). And overlap segments show better prognosis than the segments without overlap (p<0.05). Most importantly, we can get better predictive accuracy of myocardial scar by dual isotope SPECT than the judgement by Tl or PYP SPECT alone (83.3% vs 77.8%, 68.1%). Thus, we conclude that Tc-99m PYP, Tl-201 dual isotope SPECT is useful to assess the severity of myocardial damage in the acute phase of myocardial infarction. (author)

  4. Exercise and rest Tl-201 myocardial SPECT, and low dose dobutamine echocardiography to assess myocardial viability in patients with myocardial infarction

    International Nuclear Information System (INIS)

    Toyama, Takuji; Ishida, Yoshio; Shimonagata, Tsuyoshi; Kawano, Shigeo; Beppu, Shintaro; Nishimura, Tsunehiko.

    1994-01-01

    To evaluate viability of infarcted myocardium, findings of Tl-201 myocardial SPECT were compared with those of low-dose dobutamine (DOB) echocardiography. The subjects were 19 patients with myocardial infarction (23 infarcted zones), consisting of 16 men and 3 women. Findings on myocardial SPECT were classified as evidence of myocardial viability (14 zones, Group A) and no evidence of myocardial viability (9 zones, Group B). For both groups, wall motion and regional % uptake (%UP) were obtained. DOB echocardiography revealed an improvement in 5 of 8 akinesis zones in Group A. In addition, one other zone was found improved by follow-up examination. Six hypokinesis zones were all found improved on DOB echocardiography. Out of a total of 14 akinesis or hypokinesis zones, 11 (79%) showed improvement on DOB echocardiography in Group A. In Group B, all akinesis zones remained unchanged on DOB echocardiography, although one zone was improved by follow-up examination. In 11 zones in which wall motion was improved on DOB echocardiography, %UT was increased by an average of 58% on 4 hr-delayed images and 70% on resting images. The corresponding figures for 12 zones which did not improve on DOB echocardiography were 49% and 50% on the average, respectively. In conclusion, low-dose DOB echocardiography appeared to reflect viability of severely infarcted myocardium, although it had a slightly lower sensitivity than convensional Tl-201 myocardial SPECT in its ability to detect. (N.K.)

  5. Positron emission computed tomography

    International Nuclear Information System (INIS)

    Grover, M.; Schelbert, H.R.

    1985-01-01

    Regional mycardial blood flow and substrate metabolism can be non-invasively evaluated and quantified with positron emission computed tomography (Positron-CT). Tracers of exogenous glucose utilization and fatty acid metabolism are available and have been extensively tested. Specific tracer kinetic models have been developed or are being tested so that glucose and fatty acid metabolism can be measured quantitatively by Positron-CT. Tracers of amino acid and oxygen metabolism are utilized in Positron-CT studies of the brain and development of such tracers for cardiac studies are in progress. Methods to quantify regional myocardial blood flow are also being developed. Previous studies have demonstrated the ability of Positron-/CT to document myocardial infarction. Experimental and clinical studies have begun to identify metabolic markers of reversibly ischemic myocardium. The potential of Positron-CT to reliably detect potentially salvageable myocardium and, hence, to identify appropriate therapeutic interventions is one of the most exciting applications of the technique

  6. The usefulness of dipyridamole thallium-201 single photon emission computed tomography for predicting perioperative cardiac events in patients undergoing non-cardiac vascular surgery

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Tao; Kuwabara, Yasuo; Tsutsui, Hiroyuki; Sasaki, Masayuki; Nakagawa, Makoto; Koga, Hirofumi; Kaneko, Kouichirou; Komori, Kimihiro; Masuda, Kouji [Kyushu Univ., Fukuoka (Japan). Graduate School of Medical Sciences)

    2002-02-01

    The aim of this study was to evaluate the usefulness of dipyridamole Tl-201 myocardium single photon emission computed tomography ({sup 201}Tl-SPECT) for predicting perioperative cardiac events in patients with arteriosclerosis obliterans (ASO) and abdominal aortic aneurysm (AAA) undergoing non-cardiac vascular surgery. Preoperative dipyridamole {sup 201}Tl-SPECT imaging in association with clinical risk assessment was performed in 224 consecutive patients (97 ASO and 127 AAA). The patients were classified into three groups, including low-risk (n=173, 77%), intermediate-risk (n=39, 18%), and high-risk (n=12, 5%) groups according to the clinical risk stratification. The prevalence of reversible Tl-201 defect was significantly higher in the high-risk group than that in the low-risk group (83% vs. 14%, p<0.001). In 180 patients who underwent vascular surgery, 9 patients (5.0%) had perioperative cardiac events, including heart failure (n=1), unstable angina (n=2), and other cardiac events such as arrhythmias (n=6). The clinical variables including the clinical risk stratification did not significantly correlate with the perioperative cardiac events. In contrast, the reversible defect on {sup 201}Tl-SPECT was the only variable to predict perioperative cardiac events by a stepwise logistic regression analysis (odds ratio 7.0, 95% confidence interval 1.7-28.0, p=0.007). It was also a significant predictor of perioperative cardiac events in a subgroup of low risk patients (odds ratio 11.6, 95% confidence interval 2.3-57.4, p=0.004). The sensitivity and specificity of the reversible defect for predicting perioperative cardiac events were 55.6% and 84.8% in all operated patients, and 57.1% and 89.7% in low risk patients, respectively. The preoperative dipyridamole {sup 201}Tl-SPECT was useful for predicting perioperative cardiac events in patients with vascular diseases, even in patients identified as having a low risk based on the clinical risk assessment. (author)

  7. Emission computed tomography

    International Nuclear Information System (INIS)

    Phelps, M.E.

    1977-01-01

    Although there are many common aspects to x-ray transmission and radionuclide emission (ECT) computerized tomography, there are added difficulties and a number of particular factors which form the basis of ECT. The relationship between the physical factors, system design, methodologic approach and assumptions of ECT is discussed. The instrumentation design and application strategies in ECT at this time are diverse and in a rapid stage of development. The approaches are divided into two major categories of Single Photon Counting (SPC) employing scanner and camera concepts with radionuclides of 99 /sup m/Tc, 201 Tl, 123 I etc., and Annihilation Coincidence Detection (ACD) of positron-emitting radionuclides. Six systems in the former and ten systems in the latter category, with examples of typical studies, illustrate the different approaches

  8. Detection of myocardial viability could be improved by rest GIK (glucose-insulin-potassium solution)-Tc 99m sestamibi compared with TL-201 reinjection, in post myocardial infarction patients.

    Science.gov (United States)

    Orea, Arturo; Castillo, Lilia; Ochoa, Víctor; Rull, Juan Antonio; Gómez-Pérez, Francisco; Rebollar, Verónica; Sepulveda, Jesus; Dorantes, Joel; Asensio, Enrique; Oseguera, Jorge; González, Ofelia

    2004-01-01

    GIK solutions improve detection of myocardium viability after acute infarction because they could change the metabolic conditions, improving myocardial perfusion defects. Seventy four patients (52 men, 22 women, mean age 53.3.08 +/- 12.14 years) with previous myocardial infarction (evolution time, 4.2 +/- 3.1 months) underwent pharmacological stress (dipyridamole), rest redistribution and reinjection Tl-201 image as well rest/stress Tc-99m Sestamibi, after the intravenous administration of GIK (200 g glucose +/- 30 UI regular insuline +/- 40 mEq potassiumchloride/500 mL in continuous infusion during 3 hours), Group A (N = 22) or oral administration of 70 g of glucose+/- 40 mEq of potassium chloride taking in advantage the endogenous insulin secretion, to non-diabetic patients (group B = GB, N = 26) and group C (GC, diabetic patients N = 26). All of the 74 patients received 10 mg of sublingual Isorbide previous to 25 mCi of Tc99m Sestamibi administration in a different 2 days protocol. A total of 1,480 myocardial segments were assessed and numbered, and the severity of perfusion defects in the segments involved, were compared between Thallium 201 rest reinjection and GIK-MIBI as the main objective of the study. Involved territories number: 4.02 +/- 2.50 vs. 6.88 +/- 2.12, p = 0.005 for AD; 5.2 +/- 1.44 vs. 6.35 +/- 1.11, p = 0.05 for RC and 1.58 +/- 1.01 vs. 2.05 +/- 1.05, p = 0.05 Cx. For GIK-MIBI vs. Tl-201 reinjection respectively, and defect severity: 8.2 +/- 6.04 vs. 13.22 +/- 5.38, p = 0.01 for LAD; 11.72 +/- 5.08 vs. 15.13 +/- 4.42, p = 0.005 for RC and 2.66 +/- 2.09 vs. 4.69 +/- 3.58, p = 0.003 Cx . For GIK-MIBI vs. Tl-201 reinjection respectively, were found. Our data suggest that GIK-MIBI protocol is a safe and easy procedure which improves the detection of perfusion reversible defects compared with Tl-201 reinjection, obtaining better information regarding myocardial viability, with lower acquisition time and less cost.

  9. A comparative study between TL-201 SPECT myocardial perfusion scintigraphy and dobutamine stress echocardiography in the detection of coronary artery disease at the Philippine Heart Center

    International Nuclear Information System (INIS)

    Ogbac, R.V.; Martinez, A.O.; Obaldo, J.M.; Monzon, O.P.; Torres, J.F.; Rondilla, L.W.S.; Yap, J.S.; Flores, V.B.; Santos, R.J.; Jara, R.D.

    1996-01-01

    Although thallium-201 SPECT myocardial perfusion scintigraphy (MPS) has shown considerable accuracy for the detection of coronary artery disease (CAD), dobutamine stress echocardiography (DSE), a relatively new method for the detection of CAD had been recently utilized at the Philippine Heart Center. To assess its diagnostic worth versus that of thallium-201 spect myocardial scintigraphy (MPS), we studied 18 patients who underwent both procedures. Coronary angiography (CA) was used as the gold standard. MPS was performed with maximal treadmill exercise or with dipyridamole (0.568 mg/kg over 4 minutes) and Tl-201 was injected at peak stress. DSE was performed by infusing dobutamine at an increment of 5 μg/kg/min up to a maximum of 40. Atropine (0.01%) was added when 85% of maximum predicted heart rate is not achieved. Significant stenosis (>70%) was found in 16 out of 18 patients by CA. The sensitivity for the presence of CAD was 88% (14/16) and 69% (11/16) for MPS and DSE respectively. Specificity was 100% (2/2) for both. PPV was 100% for both while NPV was 50% and 29% for MPS and DSE respectively. Diagnostic accuracies were 89% and 72% for MPS and DSE respectively (P>0.05). Sensitivity for detecting left anterior descending artery (LAD) lesion was 71% 64% for MPS and DSE respectively; specificity was 75% and 100% respectively. For the left circumplex artery (LCX) lesion, both MPS and DSE had a sensitivity of 62% and specificity of 60%. Likewise for the right coronary artery (RCA) lesion, both had a sensitivity of 66% and specificity of 50%. Diagnostic accuracies were equal for both tests at 72% for LAD; 61% for LCX; and 61% for RCA. Kappa tests for association shows ρ values of >0.05 for overall and individual CAD detection suggesting no significant difference between MPS and DSE. Although there is a trend showing better detection of CAD with MPS, this particular study shows that both tests are comparable with regards to detection of the presence of CAD and of

  10. Positron Emission Tomography - Computed Tomography (PET/CT)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Positron Emission Tomography - Computed Tomography (PET/CT) Positron emission tomography (PET) ... Emission Tomography – Computed Tomography (PET/CT)? What is Positron Emission Tomography – Computed Tomography (PET/CT) Scanning? Positron emission tomography, ...

  11. Chemical emission rates from personal computers

    DEFF Research Database (Denmark)

    Nakagawa, T.; Wargocki, Pawel; Tanabe, S.

    2003-01-01

    Chemical emission measurements from different brands of personal computers (PCs) were conducted in a 1 m3 glass chamber. Eight PCs were tested individually. Each consisted of the same brand of PC tower and one of the 4 different brands of PC monitors. Within each brand both cathode-ray tube (CRT...

  12. Comparison of dobutamine-stress magnetic resonance imaging and dipyridamole-Tl-201-SPECT as alternative strategies for the detection of coronary artery disease in patients not suitable for stress-echocardiography

    International Nuclear Information System (INIS)

    Schmidt, M.; Theissen, P.; Voth, E.; Schicha, H.; Jochims, M.; Baer, F.M.; Crnac, J.; Schneider, C.A.; Erdmann, E.

    2001-01-01

    Aim: During the past decade stress-echocardiography has gained increasing popularity for detection of myocardial ischemia in patients with coronary artery disease. However, about 10% to 15% of the patients submitted for stress-echocardiography do not have an adequate acoustic window. The purpose of this study was to compare high-dose dobutamine-stress magnetic resonance imaging (dobutamine-MRI) with dipyridamole-Tl-201-SPECT (dipyridamole-SPECT) as alternative strategies for detection of myocardial ischemia in patients with inadequate image quality by stress-echocardiography. Patients and Methods: Of 296 patients which were consecutively submitted to stress-echo-cardiography 45 patients (15%) had two or more segments that could not be evaluated according to the 16-segment-model of the American Society of Echocardiography. They underwent dobutamine-MRI and dipyridamole-SPECT studies, which were evaluated using a 28-segment modell. Myocardial segments were attributed to perfusion territories of the coronary arteries. The results of ischemia detection were compared to the results of coronary angiography (stenosis ≥50%). Results: In comparison to coronary angiography dobutamine-MRI yielded a sensitivity of 87%, a specificity of 86%, a positive predictive value of 93%, a negative predictive value of 75% and a diagnostic accuracy of 86%. For dipyridamole-SPECT results were 90%, 86%, 93%, 80% and 89%, respectively. These values were not significantly different. Conclusions: In patients not suitable for stress-echocardiography, both dobutamine-MRI and dipyridamole-SPECT are reliable strategies for detection of myocardial ischemia. Selection is dependent on the patient criteria, technical considerations, local logistics and experience of the observer. (orig.) [de

  13. Physics and instrumentation of emission computed tomography

    International Nuclear Information System (INIS)

    Links, J.M.

    1986-01-01

    Transverse emission computed tomography can be divided into two distinct classes: single photon emission computed tomography (SPECT) and positron emission tomography (PET). SPECT is usually accomplished with specially-adapted scintillation cameras, although dedicated SPECT scanners are available. The special SPECT cameras are standard cameras which are mounted on gantries that allow 360 degree rotation around the long axis of the head or body. The camera stops at a number of angles around the body (usually 64-128), acquiring a ''projection'' image at each stop. The data from these projections are used to reconstruct transverse images with a standard ''filtered back-projection'' algorithm, identical to that used in transmission CT. Because the scintillation camera acquires two-dimensional images, a simple 360 degree rotation around the patient results in the acquisition of data for a number of contiguous transverse slices. These slices, once reconstructed, can be ''stacked'' in computer memory, and orthogonal coronal and sagittal slices produced. Additionally, reorienting algorithms allow the generation of slices that are oblique to the long axis of the body

  14. Clinical significance of scintigraphy in pulmonary aspergilloma

    International Nuclear Information System (INIS)

    Fujii, Tadashige; Tanaka, Masao; Nakatsuka, Tatsuya; Takeda, Tadashi; Yoshimura, Kazuhiko; Kobayashi, Toshio; Handa, Kenjiro

    1992-01-01

    In order to study the scintigraphic findings related to the pathophysiology of pulmonary aspergilloma, chest scintigraphy with Tl-201 chloride and perfusion lung scintigraphy were performed in 18 and 19 patients with pulmonary aspergilloma, respectively. In Tl-201 scintigraphy, accumulation of Tl-201 in the diseased areas related to Aspergillus infection was observed in 18 of 19 foci. Roentgenographic findings related to the accumulation of Tl-201 in the lesion were thickness of the cavity wall and pleural thickening adjacent to the cavity, but they showed no relation to the size of the fungus ball, and 2 cases without fungus ball showed positive results. Moreover, in Tl-201 single photon emission computed tomography, accumulation of Tl-201 was demonstrated in the area surrounding fungus ball. In addition, findings of inflammation such as leukocytosis, elevated erythrocyte sedimentation rate, positive CRP and fever were observed in more than 50% of all cases. These results suggest that tissues surrounding the fungus ball, including the cavity wall and thickned pleura undergo inflammatory process secondary to infection by Aspergillus. Perfusion lung scintigrams showed decreased perfusion in all of 19 cases, which was more marked than that expected from the chest radiograph in many cases. In Tl-201 myocardial scintigraphy, visualization of the right ventricle was observed in 15 of 18 cases. Tl-201 chest scintigraphy and perfusion lung scintigraphy are useful for evaluation of the activity of the disease process, right ventricular overloading, and regional perfusion in pulmonary aspergilloma. (author)

  15. Computations of NOx emissions of domestic boilers

    Energy Technology Data Exchange (ETDEWEB)

    Thevenin, D. [Ecole Centrale de Paris, 92 - Chatenay-Malabry (France). EM2C Lab.; Gicquel, O.; Darabiha, N.

    2001-07-01

    Due to severe regulations concerning pollutant emissions, practical devices using combustion to release energy must be designed from the start using accurate, predictive numerical tools. A partially premixed methane/air flame in a two-dimensional configuration is investigated in this work. This configuration is close to those used in real domestic gas boilers. The flame structure and flow pattern are calculated using complex chemistry and detailed transport models. A post-processing method is then used to predict NO emission. Computations are performed for two configurations. The two cases have the same primary and secondary mass flow-rates and equivalence ratio. The only difference between them is the introduction of an insert inside the primary injector. Both results have been compared to measurements. Calculations are found to be in good agreement with the flame shapes observed experimentally. The classical burner shows a Bunsen-type flame while the one with an insert has a totally different shape (butterfly-type flame). NO emission levels are also well predicted in both configurations. The butterfly flame induces a reduction in NO emission. This reduction seems to be due to the increased mixing between the burnt gases and the secondary air jet, which homogenizes the temperature distribution and reduces the maximum temperature. (orig.)

  16. An introduction to emission computed tomography

    International Nuclear Information System (INIS)

    Williams, E.D.

    1985-01-01

    This report includes salient features of the theory and an examination of practical considerations for someone who is using or introducing tomography, selecting equipment for it or wishing to develop a clinical application. Emphasis is on gamma camera tomography. The subject is dealt with under the following headings: emission computed and gamma camera tomography and the relationship to other medical imaging techniques, the tomographic reconstruction technique theory, rotating gamma camera tomography, attenuation correction and quantitative reconstruction, other single photon tomographic techniques, positron tomography, image display, clinical application of single photon and positron tomography, and commercial systems for SPECT. Substantial bibliography. (U.K.)

  17. Neutron stimulated emission computed tomography: Background corrections

    International Nuclear Information System (INIS)

    Floyd, Carey E.; Sharma, Amy C.; Bender, Janelle E.; Kapadia, Anuj J.; Xia, Jessie Q.; Harrawood, Brian P.; Tourassi, Georgia D.; Lo, Joseph Y.; Kiser, Matthew R.; Crowell, Alexander S.; Pedroni, Ronald S.; Macri, Robert A.; Tajima, Shigeyuki; Howell, Calvin R.

    2007-01-01

    Neutron stimulated emission computed tomography (NSECT) is an imaging technique that provides an in-vivo tomographic spectroscopic image of the distribution of elements in a body. To achieve this, a neutron beam illuminates the body. Nuclei in the body along the path of the beam are stimulated by inelastic scattering of the neutrons in the beam and emit characteristic gamma photons whose unique energy identifies the element. The emitted gammas are collected in a spectrometer and form a projection intensity for each spectral line at the projection orientation of the neutron beam. Rotating and translating either the body or the beam will allow a tomographic projection set to be acquired. Images are reconstructed to represent the spatial distribution of elements in the body. Critical to this process is the appropriate removal of background gamma events from the spectrum. Here we demonstrate the equivalence of two background correction techniques and discuss the appropriate application of each

  18. Emission computer tomography of the left ventricle

    Energy Technology Data Exchange (ETDEWEB)

    Semmler, W.; Felix, R.; Calder, D.; Golde, G.; Botsch, H.

    1983-10-01

    Tomographic studies and time-dependent tomograms on phantoms and patients were carried out using a 7-pinhole collimator in order to study the clinical value of ECG-triggered tomographic radionuclid ventriculography. A suitable computer programme has been developed. The results have shown that it is possible to evaluate local contraction abnormalities by this method. Using a left oblique position of the collimator (LAO (45/sup 0/) - cranial (15/sup 0/)), emission computer tomography is aligned with the longitudinal axis for the heart. In this way, a single projection is sufficient to show the montility of the anterior and posterior walls and of the septum. Hypokinesis, akinesis or dyskinesis can be recognised visually. The localisation and extent of the defect can be determined through the 7-pinhole collimator. Reconstructed images of the triggered radionuclide scintigrams show excellent marginal definition. In the RAO projection the left ventricle can be seen without superimposition and images obtained which equal those of a first-pass technique.

  19. Integrated positron emission tomography/computed tomography for ...

    African Journals Online (AJOL)

    Integrated positron emission tomography/computed tomography for evaluation of mediastinal lymph node staging of non-small-cell lung cancer in a tuberculosisendemic area: A 5-year prospective observational study.

  20. Diagnostic value of thallium-201 myocardial perfusion IQ-SPECT without and with computed tomography-based attenuation correction to predict clinically significant and insignificant fractional flow reserve: A single-center prospective study.

    Science.gov (United States)

    Tanaka, Haruki; Takahashi, Teruyuki; Ohashi, Norihiko; Tanaka, Koichi; Okada, Takenori; Kihara, Yasuki

    2017-12-01

    The aim of this study was to clarify the predictive value of fractional flow reserve (FFR) determined by myocardial perfusion imaging (MPI) using thallium (Tl)-201 IQ-SPECT without and with computed tomography-based attenuation correction (CT-AC) for patients with stable coronary artery disease (CAD).We assessed 212 angiographically identified diseased vessels using adenosine-stress Tl-201 MPI-IQ-SPECT/CT in 84 consecutive, prospectively identified patients with stable CAD. We compared the FFR in 136 of the 212 diseased vessels using visual semiquantitative interpretations of corresponding territories on MPI-IQ-SPECT images without and with CT-AC.FFR inversely correlated most accurately with regional summed difference scores (rSDS) in images without and with CT-AC (r = -0.584 and r = -0.568, respectively, both P system can predict FFR at an optimal cut-off of reserved.

  1. Thallium-201 is comparable to technetium-99m-sestamibi for estimating cardiac function in patients with abnormal myocardial perfusion imaging

    Directory of Open Access Journals (Sweden)

    Ming-Che Wu

    2015-11-01

    Full Text Available We analyzed the left-ventricular functional data obtained by cardiac-gated single-photon emission computed tomography myocardial perfusion imaging (MPI with thallium-201 (Tl-201 and technetium-99m-sestamibi (MIBI protocols in different groups of patients, and compared the data between Tl-201 and MIBI. Two hundred and seventy-two patients undergoing dipyridamole stress/redistribution Tl-201 MPI and 563 patients undergoing 1-day rest/dipyridamole stress MIBI MPI were included. Higher mean stress ejection fraction (EF, rest EF, and change in EF (ΔEF were noticed in the normal MPI groups by both Tl-201 and MIBI protocols. Higher mean EF was observed in the females with normal MPI results despite their higher mean age. Comparisons between the Tl-201 and MIBI groups suggested a significant difference in all functional parameters, except for the rest end diastolic volume/end systolic volume and ΔEF between groups with negative MPI results. For the positive MPI groups, there was no significant difference in all parameters, except for the change in end diastolic volume and change in end systolic volume after stress between both protocols. The Tl-201 provides comparable left-ventricular functional data to MIBI cardiac-gated single-photon emission computed tomography in patients with positive MPI results, and may therefore be undertaken routinely for incremental functional information that is especially valuable to this patient group.

  2. Diagnosis of dementia with single photon emission computed tomography

    International Nuclear Information System (INIS)

    Jagust, W.J.; Budinger, T.F.; Reed, B.R.

    1987-01-01

    Single photon emission computed tomography is a practical modality for the study of physiologic cerebral activity in vivo. We utilized single photon emission computed tomography and N-isopropyl-p-iodoamphetamine iodine 123 to evaluate regional cerebral blood flow in nine patients with Alzheimer's disease (AD), five healthy elderly control subjects, and two patients with multi-infarct dementia. We found that all subjects with AD demonstrated flow deficits in temporoparietal cortex bilaterally, and that the ratio of activity in bilateral temporoparietal cortex to activity in the whole slice allowed the differentiation of all patients with AD from both the controls and from the patients with multi-infarct dementia. Furthermore, this ratio showed a strong correlation with disease severity in the AD group. Single photon emission computed tomography appears to be useful in the differential diagnosis of dementia and reflects clinical features of the disease

  3. Quantification of the extent of myocardial infarction by thallium-201 single photon emission computed tomography; Comparisons with postmortem findings

    Energy Technology Data Exchange (ETDEWEB)

    Ide, Hiroshi; Yamada, Hideo; Ohkawa, Shin-ichiro (Tokyo Metropolitan Geriatric Medical Center (Japan)); Sugiura, Masaya; Harumi, Ken-ichi

    1991-01-01

    The diagnostic capability of a circumferential profile analysis with a two-dimensional representation of Tl-201 myocardial SPECT depends on the normal range of thallium distribution. The present study was thus to determine the lower normal limits useful for assessing the precise extent of myocardial infarction (MI). The quantitative analysis of Tl-201 myocardial SPECT was correlated with pathological findings of the heart in 50 autopsy cases (28 with MI; 22 without MI). The lower normal limits were 2.5 standard deviations below the mean values calculated using profiles normalized to the maximum pixel count observed in each profile. Using this lower normal limit, the sensitivity was 63.8%; specificity was 87.4%; and accuracy was 80.7% for determining the extent of ischemic lesions. However, for detecting MI, the sensitivity by quantitative analysis was 97%, which was higher than that by visual analysis. Non-transmural infarction 2.5 cm in size, undetectable by visual analysis, was detected by two-dimensional polar representation. However, the specificity of detecting MI was low (59%). The detectability of MI extent varied from site to site; false negative lesions were frequent in the septal region, and false positive lesions in the posterolateral region of the dilated hypertrophic heart. In conclusion, Tl-201 myocardial SPECT is useful for evaluating MI automatically, although possible false positive diagnosis must be taken into accounts in cases of dilated hypertrophic heart. (N.K.).

  4. Positron emission tomography/computed tomography scanning for ...

    African Journals Online (AJOL)

    Background: Although the site of nosocomial sepsis in the critically ill ventilated patient is usually identifiable, it may remain occult, despite numerous investigations. The rapid results and precise anatomical location of the septic source using positron emission tomography (PET) scanning, in combination with computed ...

  5. Sensory emission rates from personal computers and television sets

    DEFF Research Database (Denmark)

    Wargocki, Pawel; Bako-Biro, Zsolt; Baginska, S.

    2003-01-01

    Sensory emissions from personal computers (PCs), PC monitors + PC towers, and television sets (TVs) having been in operation for 50, 400 and 600 h were assessed by a panel of 48 subjects. One brand of PC tower and four brands of PC monitors were tested. Within each brand, cathode-ray tube (CRT...

  6. Myocardial imaging by direct injection of thallium-201 into coronary artery

    International Nuclear Information System (INIS)

    Sugihara, Hiroki; Inagaki, Suetsugu; Kubota, Yasushi

    1988-01-01

    Myocardial perfusion images were evaluated by direct injection of Thallium (Tl)-201 into coronary artery. Approximately 0.5 - 1 mCi of Tl-201 were instilled into the right coronary artery and/or the left coronary artery after coronary arteriography. Three images were obtained in the anterior, left anterior oblique and left lateral projections. Myocardial perfusion images of single photon emission computed tomography were also acquired in some patients. An image of supreme quality could be obtained in spite of small dose of Tl-201 since there was a lack of interference from background activity. Myocardial perfusion images corresponded to areas which were supplied by left or right coronary artery respectively. And the regional myocardial blood flow distribution of a coronary artery bypass graft could be revealed by instilling Tl-201 into the graft. Further, contribution of collateral channels to myocardial perfusion was showed. Not only left ventricle but also right ventricle was clearly visualized by injection of Tl-201 into right coronary artery. But in a case with arrhythmogenic right ventricular dysplasia, there was an area of decreased tracer uptake in the apex of the right ventricle which was identified as the site of dysplasia by electrophysiologic study. We conclude that direct injection of Tl-201 into coronary artery is an useful method to clarify the correlation between coronary anatomical findings and coronary perfusion and contribution of collaterals to myocardial perfusion, and also to detect the right ventricular myopathic site. (author)

  7. Visualization and computer graphics on isotropically emissive volumetric displays.

    Science.gov (United States)

    Mora, Benjamin; Maciejewski, Ross; Chen, Min; Ebert, David S

    2009-01-01

    The availability of commodity volumetric displays provides ordinary users with a new means of visualizing 3D data. Many of these displays are in the class of isotropically emissive light devices, which are designed to directly illuminate voxels in a 3D frame buffer, producing X-ray-like visualizations. While this technology can offer intuitive insight into a 3D object, the visualizations are perceptually different from what a computer graphics or visualization system would render on a 2D screen. This paper formalizes rendering on isotropically emissive displays and introduces a novel technique that emulates traditional rendering effects on isotropically emissive volumetric displays, delivering results that are much closer to what is traditionally rendered on regular 2D screens. Such a technique can significantly broaden the capability and usage of isotropically emissive volumetric displays. Our method takes a 3D dataset or object as the input, creates an intermediate light field, and outputs a special 3D volume dataset called a lumi-volume. This lumi-volume encodes approximated rendering effects in a form suitable for display with accumulative integrals along unobtrusive rays. When a lumi-volume is fed directly into an isotropically emissive volumetric display, it creates a 3D visualization with surface shading effects that are familiar to the users. The key to this technique is an algorithm for creating a 3D lumi-volume from a 4D light field. In this paper, we discuss a number of technical issues, including transparency effects due to the dimension reduction and sampling rates for light fields and lumi-volumes. We show the effectiveness and usability of this technique with a selection of experimental results captured from an isotropically emissive volumetric display, and we demonstrate its potential capability and scalability with computer-simulated high-resolution results.

  8. Measurement of liver volume by emission computed tomography

    International Nuclear Information System (INIS)

    Kan, M.K.; Hopkins, G.B.

    1979-01-01

    In 22 volunteers without clinical or laboratory evidence of liver disease, liver volume was determined using single-photon emission computed tomography (ECT). This technique provided excellent object contrast between the liver and its surroundings and permitted calculation of liver volume without geometric assumptions about the liver's configuration. Reproducibility of results was satisfactory, with a root-mean-square error of less than 6% between duplicate measurements in 15 individuals. The volume measurements were validated by the use of phantoms

  9. Guide for computing CO2 emissions related to energy use

    International Nuclear Information System (INIS)

    Aube, F.

    2001-06-01

    This guide presents a method to calculate industry-related greenhouse gas emissions. The necessary coefficients and conversion factors were presented in easy-to-use tables. The many examples that were included with the guide show that the calculation can be easily used to assess a company's annual contribution to global warming. Greenhouse gas emissions, or carbon dioxide equivalent emissions associated with energy use can be calculated by gathering all the energy bills for the year and determining the amounts of each of the fuels used, along with the amount of electricity consumed. If the computation involves finding the environmental impact caused by adding or replacing equipment, it is necessary to estimate the adjusted consumption of each type of energy source. The calculation then proceeds by converting the data on the energy bills into reference units to simplify the remaining calculations. Energy content is expressed in megajoules per unit of quantity for most types of energy carriers such as electricity (hydro or nuclear), steam, natural gas, ethane, propane, coal, or petroleum products. The guide includes two tables indicating how to convert the units of values found on typical energy bills. A table indicating the carbon dioxide equivalent emission factors for electricity by province in 1998 was included. The average for Canada was 0.222 t/MWh. The global warming potential (GWP) for carbon dioxide, nitrogen oxide, and methane are 1, 310, and 21 GWP respectively. 6 tabs

  10. Iterative concurrent reconstruction algorithms for emission computed tomography

    International Nuclear Information System (INIS)

    Brown, J.K.; Hasegawa, B.H.; Lang, T.F.

    1994-01-01

    Direct reconstruction techniques, such as those based on filtered backprojection, are typically used for emission computed tomography (ECT), even though it has been argued that iterative reconstruction methods may produce better clinical images. The major disadvantage of iterative reconstruction algorithms, and a significant reason for their lack of clinical acceptance, is their computational burden. We outline a new class of ''concurrent'' iterative reconstruction techniques for ECT in which the reconstruction process is reorganized such that a significant fraction of the computational processing occurs concurrently with the acquisition of ECT projection data. These new algorithms use the 10-30 min required for acquisition of a typical SPECT scan to iteratively process the available projection data, significantly reducing the requirements for post-acquisition processing. These algorithms are tested on SPECT projection data from a Hoffman brain phantom acquired with a 2 x 10 5 counts in 64 views each having 64 projections. The SPECT images are reconstructed as 64 x 64 tomograms, starting with six angular views. Other angular views are added to the reconstruction process sequentially, in a manner that reflects their availability for a typical acquisition protocol. The results suggest that if T s of concurrent processing are used, the reconstruction processing time required after completion of the data acquisition can be reduced by at least 1/3 T s. (Author)

  11. Single photon emission computed tomography in AIDS dementia complex

    International Nuclear Information System (INIS)

    Pohl, P.; Vogl, G.; Fill, H.; Roessler, H.Z.; Zangerle, R.; Gerstenbrand, F.

    1988-01-01

    Single photon emission computed tomography (SPECT) studies were performed in AIDS dementia complex using IMP in 12 patients (and HM-PAO in four of these same patients). In all patients, SPECT revealed either multiple or focal uptake defects, the latter corresponding with focal signs or symptoms in all but one case. Computerized tomography showed a diffuse cerebral atrophy in eight of 12 patients, magnetic resonance imaging exhibited changes like atrophy and/or leukoencephalopathy in two of five cases. Our data indicate that both disturbance of cerebral amine metabolism and alteration of local perfusion share in the pathogenesis of AIDS dementia complex. SPECT is an important aid in the diagnosis of AIDS dementia complex and contributes to the understanding of the pathophysiological mechanisms of this disorder

  12. FDG positron emission computed tomography in a study of aphasia

    International Nuclear Information System (INIS)

    Metter, E.J.; Wasterlain, C.G.; Kuhl, D.E.; Hanson, W.R.; Phelps, M.E.

    1981-01-01

    Positron emission computed tomography (PECT) using 18F-2-fluoro-2-deoxy-D-glucose (FDG) was used to investigate the correlations between clinical status, anatomy (as described by CT), and metabolism in five patients with stable aphasia resulting from ischemic cerebral infarction. Local cerebral metabolic activity was diminished in an area larger than the area of infarction demonstrated by CT. In one patient, FDG PECT revealed a metabolic lesion that probably caused the aphasic syndrome and was not apparent by CT. The data suggest that reliance on CT in delineating the extent of the brain lesion in aphasia or other neuropsychological defects can be misleading; FDG PECT may provide important additional information. Two patients with similar metabolic lesions had very different clinical syndromes, showing that even when currently available methods are combined, major gaps remain in clinicoanatomical correlations in aphasia

  13. High-performance computing and networking as tools for accurate emission computed tomography reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Passeri, A. [Dipartimento di Fisiopatologia Clinica - Sezione di Medicina Nucleare, Universita` di Firenze (Italy); Formiconi, A.R. [Dipartimento di Fisiopatologia Clinica - Sezione di Medicina Nucleare, Universita` di Firenze (Italy); De Cristofaro, M.T.E.R. [Dipartimento di Fisiopatologia Clinica - Sezione di Medicina Nucleare, Universita` di Firenze (Italy); Pupi, A. [Dipartimento di Fisiopatologia Clinica - Sezione di Medicina Nucleare, Universita` di Firenze (Italy); Meldolesi, U. [Dipartimento di Fisiopatologia Clinica - Sezione di Medicina Nucleare, Universita` di Firenze (Italy)

    1997-04-01

    It is well known that the quantitative potential of emission computed tomography (ECT) relies on the ability to compensate for resolution, attenuation and scatter effects. Reconstruction algorithms which are able to take these effects into account are highly demanding in terms of computing resources. The reported work aimed to investigate the use of a parallel high-performance computing platform for ECT reconstruction taking into account an accurate model of the acquisition of single-photon emission tomographic (SPET) data. An iterative algorithm with an accurate model of the variable system response was ported on the MIMD (Multiple Instruction Multiple Data) parallel architecture of a 64-node Cray T3D massively parallel computer. The system was organized to make it easily accessible even from low-cost PC-based workstations through standard TCP/IP networking. A complete brain study of 30 (64 x 64) slices could be reconstructed from a set of 90 (64 x 64) projections with ten iterations of the conjugate gradients algorithm in 9 s, corresponding to an actual speed-up factor of 135. This work demonstrated the possibility of exploiting remote high-performance computing and networking resources from hospital sites by means of low-cost workstations using standard communication protocols without particular problems for routine use. The achievable speed-up factors allow the assessment of the clinical benefit of advanced reconstruction techniques which require a heavy computational burden for the compensation effects such as variable spatial resolution, scatter and attenuation. The possibility of using the same software on the same hardware platform with data acquired in different laboratories with various kinds of SPET instrumentation is appealing for software quality control and for the evaluation of the clinical impact of the reconstruction methods. (orig.). With 4 figs., 1 tab.

  14. Single-photon emission computed tomography and early death in acute ischemic stroke

    NARCIS (Netherlands)

    Limburg, M.; van Royen, E. A.; Hijdra, A.; de Bruïne, J. F.; Verbeeten, B. W.

    1990-01-01

    Single-photon emission computed tomography with thallium-201-labeled diethyldithiocarbamate was performed in 26 consecutive patients less than or equal to 24 hours after a supratentorial brain infarction. Computed tomography excluded other relevant pathology. Two observers assessed the initial

  15. Positron emission tomography/computed tomography imaging and rheumatoid arthritis.

    Science.gov (United States)

    Wang, Shi-Cun; Xie, Qiang; Lv, Wei-Fu

    2014-03-01

    Rheumatoid arthritis (RA) is a phenotypically heterogeneous, chronic, destructive inflammatory disease of the synovial joints. A number of imaging tools are currently available for evaluation of inflammatory conditions. By targeting the upgraded glucose uptake of infiltrating granulocytes and tissue macrophages, positron emission tomography/computed tomography with fluorine-18 fluorodeoxyglucose ((18) F-FDG PET/CT) is available to delineate inflammation with high sensitivity. Recently, several studies have indicated that FDG uptake in affected joints reflects the disease activity of RA. In addition, usage of FDG PET for the sensitive detection and monitoring of the response to treatment has been reported. Combined FDG PET/CT enables the detailed assessment of disease in large joints throughout the whole body. These unique capabilities of FDG PET/CT imaging are also able to detect RA-complicated diseases. Therefore, PET/CT has become an excellent ancillary tool to assess disease activity and prognosis in RA. © 2014 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

  16. Proceedings of clinical SPECT [single photon emission computed tomography] symposium

    International Nuclear Information System (INIS)

    1986-09-01

    It has been five years since the last in-depth American College of Nuclear Physicians/Society of Nuclear Medicine Symposium on the subject of single photon emission computed tomography (SPECT) was held. Because this subject was nominated as the single most desired topic we have selected SPECT imaging as the basis for this year's program. The objectives of this symposium are to survey the progress of SPECT clinical applications that have taken place over the last five years and to provide practical and timely guidelines to users of SPECT so that this exciting imaging modality can be fully integrated into the evaluation of pathologic processes. The first half was devoted to a consideration of technical factors important in SPECT acquisition and the second half was devoted to those organ systems about which sufficient clinical SPECT imaging data are available. With respect to the technical aspect of the program we have selected the key areas which demand awareness and attention in order to make SPECT operational in clinical practice. These include selection of equipment, details of uniformity correction, utilization of phantoms for equipment acceptance and quality assurance, the major aspect of algorithms, an understanding of filtered back projection and appropriate choice of filters and an awareness of the most commonly generated artifacts and how to recognize them. With respect to the acquisition and interpretation of organ images, the faculty will present information on the major aspects of hepatic, brain, cardiac, skeletal, and immunologic imaging techniques. Individual papers are processed separately for the data base

  17. Single photon emission computed tomography in lumbar degenerative spondylolisthesis

    International Nuclear Information System (INIS)

    Ito, S.; Muro, T.; Eisenstein, S.

    1998-01-01

    Analysis of single photon emission computed tomographic images and plain X-ray films of the lumbar vertebrae was performed in 15 patients with lumbar spondylosis and 15 patients with lumbar degenerative spondylolisthesis. The facet joint and osteophyte images were observed in particular, and the slipping ratio of spondylolisthetic vertebrae was determined. The slipping ratio of degenerative spondylolisthesis ranged from 11.8 % to 22.3 %. Hot uptake of 99mTc-HMDP by both L4-5 facet joints was significantly greater in the patients with degenerative spondylolisthesis than in those with lumbar spondylosis. The hot uptake by the osteophytes in lumbar spondylosis was nearly uniform among the three inferior segments, L3-4, L4-5 and L5-S, but was localized to the spondylolisthetic vertebrae, L4-5, or L5-S, in the patients with spondylolisthesis. Half of the osteophytes with hot uptake were assigned to the 3rd degree of Nathan's grading. It was suggested that stress was localized to the slipping vertebrae and their facet joints in patients with lumbar degenerative spondylolisthesis. (author)

  18. 67Ga-emission computed tomography in bronchogenic carcinoma

    International Nuclear Information System (INIS)

    Ichiya, Yuichi; Oshiumi, Yoshihiko; Kuwabara, Yasuo; Wada, Makoto; Ayabe, Zenji; Matsuura, Keiichi

    1982-01-01

    Both conventional 67 Ga scintigraphy and 67 Ga emission computed tomography (ECT) were performed in 36 patients with bronchogenic carcinoma to evaluate clinical significance of 67 Ga-ECT as an adjunctive method. Each patient received 111 -- 185 MBq (3 -- 5 mCi) of 67 Ga-citrate intravenously. A rotation #betta# camera (Shimadzu LFOV-E) was used for ECT study, and a #betta# camera (Searle LFOV) was used for conventional scintigraphy. The detectability of 67 Ga scintigraphy with ECT in primary tumors and regional lymph node metastases was compared retrospectively with that of conventional 67 Ga scintigraphy alone. There was little improvement in detection of primary and metastatic lesions by adding 67 Ga-ECT. Only 3 primary tumors were demonstrated more distinctly by 67 Ga-ECT. However, there was no lesion which was detected only by 67 Ga-ECT. Our data indicate that inclusion of 67 Ga-ECT in the routine examination is unnecessary in cases with bronchogenic carcinoma. (author)

  19. Gallium tomoscintigraphic imaging of esophageal cancer using emission computed tomography

    International Nuclear Information System (INIS)

    Hattori, Takao; Nakagawa, Tsuyoshi; Takeda, Kan; Maeda, Hisato; Taguchi, Mitsuo

    1983-01-01

    Emission computed tomography (ECT) was clinically evaluated in 67 Ga imaging of esophageal cancer. ECT system used in this study is equipped with opposed dual large-field-of-view cameras (GCA 70A-S, Toshiba Co.). Data were acquired by rotating the two cameras 180 0 about the longitudinal axis of the patient. Total acquisition time was about 12 minutes. Multiple slices of transaxial, sagittal and coronal sections were reconstructed in a 64 x 64 matrix form using convolution algorithms. In three out of six cases studied the tumor uptake was not detected on conventional images, because the lesion was small, concentration of activity was poor or the lesion activity was overlapped with the neighbouring activities distributed to normal organs such as sternum, vertebra, liver and hilus. On ECT images, by contrast, abnormal uptake of the tumors was definitively detected in all the six cases. ECT imaging was also useful in estimating the effect of treatment by the decrease in 67 Ga concentration. We have devised a special technique to repeat ECT scan with a thin tube filled with 67 Ga solution inserted through the esophagus. By this technique, comparing paired images with and without the tube activity, exact location of the uptake against the esophagus and extraesophageal extension of the disease could be accurately evaluated in a three-dimensional field of view. ECT in gallium scanning is expected to be of great clinical value to elevate the confidence level of diagnosis in detecting, localizing and following up the diseases. (author)

  20. Brain single photon emission computed tomography in neonates

    Energy Technology Data Exchange (ETDEWEB)

    Denays, R.; Van Pachterbeke, T.; Tondeur, M.; Spehl, M.; Toppet, V.; Ham, H.; Piepsz, A.; Rubinstein, M.; Nol, P.H.; Haumont, D. (Free Universities of Brussels (Belgium))

    1989-08-01

    This study was designed to rate the clinical value of ({sup 123}I)iodoamphetamine (IMP) or ({sup 99m}Tc) hexamethyl propylene amine oxyme (HM-PAO) brain single photon emission computed tomography (SPECT) in neonates, especially in those likely to develop cerebral palsy. The results showed that SPECT abnormalities were congruent in most cases with structural lesions demonstrated by ultrasonography. However, mild bilateral ventricular dilatation and bilateral subependymal porencephalic cysts diagnosed by ultrasound were not associated with an abnormal SPECT finding. In contrast, some cortical periventricular and sylvian lesions and all the parasagittal lesions well visualized in SPECT studies were not diagnosed by ultrasound scans. In neonates with subependymal and/or intraventricular hemorrhage the existence of a parenchymal abnormality was only diagnosed by SPECT. These results indicate that ({sup 123}I)IMP or ({sup 99m}Tc)HM-PAO brain SPECT shows a potential clinical value as the neurodevelopmental outcome is clearly related to the site, the extent, and the number of cerebral lesions. Long-term clinical follow-up is, however, mandatory in order to define which SPECT abnormality is associated with neurologic deficit.

  1. Single-Photon Emission Computed Tomography (SPECT) in childhood epilepsy

    International Nuclear Information System (INIS)

    Gulati, Sheffali; Kalra, Veena; Bal, C.S.

    2000-01-01

    The success of epilepsy surgery is determined strongly by the precise location of the epileptogenic focus. The information from clinical electrophysiological data needs to be strengthened by functional neuroimaging techniques. Single photon emission computed tomography (SPECT) available locally has proved useful as a localising investigation. It evaluates the regional cerebral blood flow and the comparison between ictal and interictal blood flow on SPECT has proved to be a sensitive nuclear marker for the site of seizure onset. Many studies justify the utility of SPECT in localising lesions to possess greater precision than interictal scalp EEG or anatomic neuroimaging. SPECT is of definitive value in temporal lobe epilepsy. Its role in extratemporal lobe epilepsy is less clearly defined. It is useful in various other generalized and partial seizure disorders including epileptic syndromes and helps in differentiating pseudoseizures from true seizures. The need for newer radiopharmaceutical agents with specific neurochemical properties and longer shelf life are under investigation. Subtraction ictal SPECT co-registered to MRI is a promising new modality. (author)

  2. Therapy response evaluation with positron emission tomography-computed tomography.

    Science.gov (United States)

    Segall, George M

    2010-12-01

    Positron emission tomography-computed tomography with F-18-fluorodeoxyglucose is widely used for evaluation of therapy response in patients with solid tumors but has not been as readily adopted in clinical trials because of the variability of acquisition and processing protocols and the absence of universal response criteria. Criteria proposed for clinical trials are difficult to apply in clinical practice, and gestalt impression is probably accurate in individual patients, especially with respect to the presence of progressive disease and complete response. Semiquantitative methods of determining tissue glucose metabolism, such as standard uptake value, can be a useful descriptor for levels of tissue glucose metabolism and changes in response to therapy if technical quality control measures are carefully maintained. The terms partial response, complete response, and progressive disease are best used in clinical trials in which the terms have specific meanings and precise definitions. In clinical practice, it may be better to use descriptive terminology agreed upon by imaging physicians and clinicians in their own practice. Copyright © 2010. Published by Elsevier Inc.

  3. [Positron emission tomography/computed tomography for lung cancer staging].

    Science.gov (United States)

    Ladrón de Guevara H, David; Furnaro L, Francisca; Yévenes A, Sebastián; Clavero R, José Miguel; Lazo P, David; Rodríguez D, Patricio; Piottante B, Antonio; Pefaur D, Raúl; Pardo B, Claudio

    2015-01-01

    PET/CT (Positron Emission Tomography/Computed Tomography) is widely used in nodal and metastatic staging of lung cancer patients. To analyze PET/CT detection of metastatic disease in patients with lung cancer. We reviewed retrospectively F18Fluorodeoxyglucose PET/CT scans performed between December 2008 and December 2013. We selected 143 patients aged 30 to 92 years (63% males) with confirmed lung cancer referred for staging, with no previous treatment. We reviewed whole body PET/CT and brain magnetic resonance images. SUVmax (Standardized Uptake Value maximum) of primary pulmonary lesion, hilar/mediastinal nodes, and distant metastases were calculated. Histological types encountered were adenocarcinoma in 55%, squamous-cell in 15%, small-cell in 8%, large-cell in 6% and adeno-squamous in 2%. In 22 cases (15%) histology was not available. Nodal involvement was observed in 60% of patients (44% hilar and 48% mediastinal). Skip metastases (mediastinal involvement without hilum involvement) were encountered in 17% of cases, and were significantly more common among high uptake lung tumors (p < 0.01). Best SUVmax cut-off for node involvement was 4.4 for hilum and 4.0 for mediastinum (sensibility: 86.4%, specificity: 99.8%). Sixty six patients (46.2%) showed distant metastases on PET/CT. The most common metastases were osseous in 22%, adrenal in 16%, hepatic in14%, pulmonary in 14% and cerebral in 12%. PET/CT detected a second unexpected synchronic cancer in eight patients (6%). PET/CT is accurate for nodal staging using an uptake index as SUVmax. Distant metastases are common, especially in bone, adrenal glands and liver.

  4. Proceedings of clinical SPECT (single photon emission computed tomography) symposium

    Energy Technology Data Exchange (ETDEWEB)

    1986-09-01

    It has been five years since the last in-depth American College of Nuclear Physicians/Society of Nuclear Medicine Symposium on the subject of single photon emission computed tomography (SPECT) was held. Because this subject was nominated as the single most desired topic we have selected SPECT imaging as the basis for this year's program. The objectives of this symposium are to survey the progress of SPECT clinical applications that have taken place over the last five years and to provide practical and timely guidelines to users of SPECT so that this exciting imaging modality can be fully integrated into the evaluation of pathologic processes. The first half was devoted to a consideration of technical factors important in SPECT acquisition and the second half was devoted to those organ systems about which sufficient clinical SPECT imaging data are available. With respect to the technical aspect of the program we have selected the key areas which demand awareness and attention in order to make SPECT operational in clinical practice. These include selection of equipment, details of uniformity correction, utilization of phantoms for equipment acceptance and quality assurance, the major aspect of algorithms, an understanding of filtered back projection and appropriate choice of filters and an awareness of the most commonly generated artifacts and how to recognize them. With respect to the acquisition and interpretation of organ images, the faculty will present information on the major aspects of hepatic, brain, cardiac, skeletal, and immunologic imaging techniques. Individual papers are processed separately for the data base. (TEM)

  5. Spectrum of single photon emission computed tomography/computed tomography findings in patients with parathyroid adenomas.

    Science.gov (United States)

    Chakraborty, Dhritiman; Mittal, Bhagwant Rai; Harisankar, Chidambaram Natrajan Balasubramanian; Bhattacharya, Anish; Bhadada, Sanjay

    2011-01-01

    Primary hyperparathyroidism results from excessive parathyroid hormone secretion. Approximately 85% of all cases of primary hyperparathyroidism are caused by a single parathyroid adenoma; 10-15% of the cases are caused by parathyroid hyperplasia. Parathyroid carcinoma accounts for approximately 3-4% of cases of primary disease. Technetium-99m-sestamibi (MIBI), the current scintigraphic procedure of choice for preoperative parathyroid localization, can be performed in various ways. The "single-isotope, double-phase technique" is based on the fact that MIBI washes out more rapidly from the thyroid than from abnormal parathyroid tissue. However, not all parathyroid lesions retain MIBI and not all thyroid tissue washes out quickly, and subtraction imaging is helpful. Single photon emission computed tomography (SPECT) provides information for localizing parathyroid lesions, differentiating thyroid from parathyroid lesions, and detecting and localizing ectopic parathyroid lesions. Addition of CT with SPECT improves the sensitivity. This pictorial assay demonstrates various SPECT/CT patterns observed in parathyroid scintigraphy.

  6. On the Computation of Secondary Electron Emission Models

    OpenAIRE

    Clerc, Sebastien; Dennison, JR; Hoffmann, Ryan; Abbott, Jonathon

    2006-01-01

    Secondary electron emission is a critical contributor to the charge particle current balance in spacecraft charging. Spacecraft charging simulation codes use a parameterized expression for the secondary electron (SE) yield delta(Eo) as a function of the incident electron energy Eo. Simple three-step physics models of the electron penetration, transport, and emission from a solid are typically expressed in terms of the incident electron penetration depth at normal incidence R(Eo) and the mean ...

  7. RELIABILITY OF POSITRON EMISSION TOMOGRAPHY-COMPUTED TOMOGRAPHY IN EVALUATION OF TESTICULAR CARCINOMA PATIENTS.

    Science.gov (United States)

    Nikoletić, Katarina; Mihailović, Jasna; Matovina, Emil; Žeravica, Radmila; Srbovan, Dolores

    2015-01-01

    The study was aimed at assessing the reliability of 18F-fluorodeoxyglucose positron emission tomography-computed tomography scan in evaluation of testicular carcinoma patients. The study sample consisted of 26 scans performed in 23 patients with testicular carcinoma. According to the pathohistological finding, 14 patients had seminomas, 7 had nonseminomas and 2 patients had a mixed histological type. In 17 patients, the initial treatment was orchiectomy+chemotherapy, 2 patients had orchiectomy+chemotherapy+retroperitoneal lymph node dissection, 3 patients had orchiectomy only and one patient was treated with chemotherapy only. Abnormal computed tomography was the main cause for the oncologist to refer the patient to positron emission tomography-computed tomography scan (in 19 scans), magnetic resonance imaging abnormalities in 1 scan, high level oftumor markers in 3 and 3 scans were perforned for follow-up. Positron emission tomography-computed tomography imaging results were compared with histological results, other imaging modalities or the clinical follow-up of the patients. Positron emission tomography-computed tomography scans were positive in 6 and negative in 20 patients. In two patients, positron emission tomography-computed tomography was false positive. There were 20 negative positron emission omography-computed tomography scans perforned in 18 patients, one patient was lost for data analysis. Clinically stable disease was confirmed in 18 follow-up scans performed in 16 patients. The values of sensitivty, specificity, accuracy, and positive- and negative predictive value were 60%, 95%, 75%, 88% and 90.5%, respectively. A hgh negative predictive value obtained in our study (90.5%) suggests that there is a small possibility for a patient to have future relapse after normal positron emission tomography-computed tomography study. However, since the sensitivity and positive predictive value of the study ire rather low, there are limitations of positive

  8. Strategies for displaying computer simulated three-dimensional images from emission computed tomography

    International Nuclear Information System (INIS)

    Schlusselberg, D.S.; Simon, T.R.; Smith, W.K.; Woodward, D.J.; Parkey, R.W.

    1985-01-01

    Emission computed tomography (ECT) quantitatively localizes radionuclide tracer distributions within a three-dimensional (3D) volume. Currently available techniques limit the display of this information to series of cross-sectional or rotating images. Such techniques of ten rely on special viewing equipment to synthesize the image series into a volumetric display. The authors have developed new algorithms that generate 3D images of radiotracer distributions using computerized analysis of tomographic data. Imaging strategies including transparent volumes, surface models, color-coded circumferential histograms and transparent slices are combined to produce a single image that contains the quantitative distributional information. While the images can be displayed on most raster-based display devices, they are suitable for archiving and distribution as single image photographs. This choice of formats enhances the value of the technique for communicating scintigraphic information to referring physicians while maintaining the quantitative integrity of the data. The technique has been successfully applied to a variety of ECT examination including brain, heart, liver and bone studies

  9. Diagnostic value of thallium-201 myocardial perfusion IQ-SPECT without and with computed tomography-based attenuation correction to predict clinically significant and insignificant fractional flow reserve

    Science.gov (United States)

    Tanaka, Haruki; Takahashi, Teruyuki; Ohashi, Norihiko; Tanaka, Koichi; Okada, Takenori; Kihara, Yasuki

    2017-01-01

    Abstract The aim of this study was to clarify the predictive value of fractional flow reserve (FFR) determined by myocardial perfusion imaging (MPI) using thallium (Tl)-201 IQ-SPECT without and with computed tomography-based attenuation correction (CT-AC) for patients with stable coronary artery disease (CAD). We assessed 212 angiographically identified diseased vessels using adenosine-stress Tl-201 MPI-IQ-SPECT/CT in 84 consecutive, prospectively identified patients with stable CAD. We compared the FFR in 136 of the 212 diseased vessels using visual semiquantitative interpretations of corresponding territories on MPI-IQ-SPECT images without and with CT-AC. FFR inversely correlated most accurately with regional summed difference scores (rSDS) in images without and with CT-AC (r = −0.584 and r = −0.568, respectively, both P system can predict FFR at an optimal cut-off of <0.80, and we propose a novel application of CT-AC to MPI-IQ-SPECT for predicting clinically significant and insignificant FFR even in nonobese patients. PMID:29390486

  10. Computational intelligence approach for NOx emissions minimization in a coal-fired utility boiler

    International Nuclear Information System (INIS)

    Zhou Hao; Zheng Ligang; Cen Kefa

    2010-01-01

    The current work presented a computational intelligence approach used for minimizing NO x emissions in a 300 MW dual-furnaces coal-fired utility boiler. The fundamental idea behind this work included NO x emissions characteristics modeling and NO x emissions optimization. First, an objective function aiming at estimating NO x emissions characteristics from nineteen operating parameters of the studied boiler was represented by a support vector regression (SVR) model. Second, four levels of primary air velocities (PA) and six levels of secondary air velocities (SA) were regulated by using particle swarm optimization (PSO) so as to achieve low NO x emissions combustion. To reduce the time demanding, a more flexible stopping condition was used to improve the computational efficiency without the loss of the quality of the optimization results. The results showed that the proposed approach provided an effective way to reduce NO x emissions from 399.7 ppm to 269.3 ppm, which was much better than a genetic algorithm (GA) based method and was slightly better than an ant colony optimization (ACO) based approach reported in the earlier work. The main advantage of PSO was that the computational cost, typical of less than 25 s under a PC system, is much less than those required for ACO. This meant the proposed approach would be more applicable to online and real-time applications for NO x emissions minimization in actual power plant boilers.

  11. Modelling Emission from Building Materials with Computational Fluid Dynamics

    DEFF Research Database (Denmark)

    Topp, Claus; Nielsen, Peter V.; Heiselberg, Per

    This paper presents a numerical model that by means of computational fluid dynamics (CFD) is capable of dealing with both pollutant transport across the boundary layer and internal diffusion in the source without prior knowledge of which is the limiting process. The model provides the concentration...

  12. Analysis on laser plasma emission for characterization of colloids by video-based computer program

    Science.gov (United States)

    Putri, Kirana Yuniati; Lumbantoruan, Hendra Damos; Isnaeni

    2016-02-01

    Laser-induced breakdown detection (LIBD) is a sensitive technique for characterization of colloids with small size and low concentration. There are two types of detection, optical and acoustic. Optical LIBD employs CCD camera to capture the plasma emission and uses the information to quantify the colloids. This technique requires sophisticated technology which is often pricey. In order to build a simple, home-made LIBD system, a dedicated computer program based on MATLAB™ for analyzing laser plasma emission was developed. The analysis was conducted by counting the number of plasma emissions (breakdowns) during a certain period of time. Breakdown probability provided information on colloid size and concentration. Validation experiment showed that the computer program performed well on analyzing the plasma emissions. Optical LIBD has A graphical user interface (GUI) was also developed to make the program more user-friendly.

  13. Myocardial scintigraphy

    International Nuclear Information System (INIS)

    Bunko, Hisashi; Hisada, Kinichi

    1982-01-01

    Among the various methods of image diagnosis of the cardiovascular disorder, nuclear cardiology provides noninvasive means for evaluation of myocardial perfusion as well as morphological and functional informations. In this article, clinical application and image diagnosis of myocardial scintigraphy including Tl-201 myocardial perfusion scintigraphy, single photon emission computed tomography with Tl-201, acute myocardial infarction scintigraphy with Tc-99m-pyrophosphate and Ga-67 imaging of the heart, were discussed. Multiplanar imaging of the heart with Tl-201 after stress and at redistribution was the accepted method for detection and evaluation of the ischemic heart disease. Although it achieved high sensitivity and specificity for ischemic heart disease, detection of the small ischemia and quantation of the regional Tl-201 accumulation were difficult with conventional multiplanar imaging. Application of emission computed tomography improved detectability and quantitativity of the ischemia. However, 7-pinhole tomography did not increase the diagnostic accuracy significantly. It had limited clinical applicability due to poor quantitativity in spite of improved image contrast and its tomographic nature. Advantage and limitation of these tomographic imaging and multiplanar imaging were discussed. Problems and prognostic significance of pyrophosphate imaging of the acute myocardial infarction were also discussed. Visualization of the heart with Ga-67 was helpful for identification of the tumor or inflammation of the heart as well as evaluation of the effect of the therapy. (author)

  14. PC-BEIS: a personal computer version of the biogenic emissions inventory system

    International Nuclear Information System (INIS)

    Pierce, T.E.; Waldruff, P.S.

    1991-01-01

    The US Environmental Protection Agency's Biogenic Emissions Inventory System (BEIS) has been adapted for use on IBM-compatible personal computers (PCs). PC-BEIS estimates hourly emissions of isoprene, α-pinene, other monoterpenes, and unidentified hydrocarbons for any county in the contiguous United States. To run the program, users must provide hourly data on ambient temperature, relative humidity, wind speed, cloud cover, and a code that identifies the particular county. This paper provides an overview of the method used to calculate biogenic emissions, shows an example application, and gives information on how to obtain a copy of the program

  15. Value of positron emission tomography and computer tomography (PET/CT) for urologic malignancies

    International Nuclear Information System (INIS)

    Boujelbene, N.; Mirimanoff, R.O.; Ozsahin, M.; Zouhair, A.; Prior, J.O.; Boubaker, A.; Azria, D.; Schaffer, M.; Gez, E.; Jichlinski, P.; Meuwly, J.Y.

    2011-01-01

    Positron emission tomography is a functional imaging technique that allows the detection of the regional metabolic rate, and is often coupled with other morphological imaging technique such as computed tomography. The rationale for its use is based on the clearly demonstrated fact that functional changes in tumor processes happen before morphological changes. Its introduction to the clinical practice added a new dimension in conventional imaging techniques. This review presents the current and proposed indications of the use of positron emission/computed tomography for prostate, bladder and testes, and the potential role of this exam in radiotherapy planning. (authors)

  16. Emission computer tomography on a Dodewaard mixed oxide fuel pin

    International Nuclear Information System (INIS)

    Buurveld, H.A.; Dassel, G.

    1993-12-01

    A nondestructive technique as well as a destructive PIE technique have been used to verify the results obtained with a newly 8-e computer tomography (GECT) system. Multi isotope Scanning (MIS), electron probe micro analysis (EPMA) and GECT were used on a mixed oxide (MOX) fuel rod from the Dodewaard reactor with an average burnup of 24 MWd/kg fuel. GECT shows migration of Cs to the periphery of fuel pellets and to radial cracks and pores in the fuel, whereas MIS shows Cs migration to pellet interfaces. The EPMA technique appeared not to be useful to show migration of Cs but, it shows the distribution of fission products from Pu. EPMA clearly shows the distribution of fission products from Pu, but did not reveal the Cs-migration. (orig./HP)

  17. Single photon emission computed tomography by using fan beam collimator

    International Nuclear Information System (INIS)

    Akiyama, Yoshihisa

    1992-01-01

    A multislice fan beam collimator which has parallel collimation along the cephalic-caudul axis of a patient and converging collimation within planes that are perpendicular to that axis was designed for a SPECT system with a rotating scintillation camera, and it was constructed by the lead casting method which was developed in recent years. A reconstruction algorithm for fan beam SPECT was formed originally by combining the reconstruction algorithm of the parallel beam SPECT with that of the fan beam X-ray CT. The algorithm for fan beam SPECT was confirmed by means of computer simulation and a head phantom filled with diluted radionuclide. Not only 99m Tc but also 123 I was used as a radionuclide. A SPECT image with the fan beam collimator was compared with that of a parallel hole, low energy, high resolution collimator which was routinely used for clinical and research SPECT studies. Both system resolution and sensitivity of the fan beam collimator were ∼20% better than those of the parallel hole collimator. Comparing SPECT images obtained from fan beam collimator with those of parallel hole collimator, the SPECT images using fan beam collimator had far better resolution. A fan beam collimator is a useful implement for the SPECT study. (author)

  18. Positron emission tomography-computed tomography has a clinical impact for patients with cervical cancer

    DEFF Research Database (Denmark)

    Sandvik, Rikke Mulvad; Jensen, Pernille Tine; Hendel, Helle W

    2011-01-01

    Many studies have found that positron emission tomography-computed tomography (PET-CT) has a high sensitivity and specificity in the identification of metastasis in cervical cancer. Herlev Hospital, Denmark, has been performing PET-CTs in stage I-IV cervical cancer since 1 May 2006. The present...

  19. Visual cortex activation recorded by dynamic emission computed tomography of inhaled xenon 133

    DEFF Research Database (Denmark)

    Henriksen, L; Paulson, O B; Lassen, N A

    1981-01-01

    Regional cerebral blood flow (CBF) was studied tomographically with 133Xe administered by inhalation over a 1-min period at a concentration of 10 mCi/l. A fast rotating ("dynamic') single-photon emission computed tomograph with four detector heads was used, an instrument that has been found to be...

  20. Positron emission tomography/computed tomography for optimized colon cancer staging and follow up

    DEFF Research Database (Denmark)

    Engelmann, Bodil Elisabeth; Loft, Annika; Kjær, Andreas

    2014-01-01

    OBJECTIVES: Optimal management of colon cancer (CC) requires detailed assessment of extent of disease. This study prospectively investigates the diagnostic accuracy of 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (PET/CT) for staging and detection of recurrence...

  1. Macroeconomic effects of CO2 emission limits : A computable general equilibrium analysis for China

    NARCIS (Netherlands)

    Zhang, ZX

    The study analyzes the macroeconomic effects of limiting China's CO2 emissions by using a time-recursive dynamic computable general equilibrium (CGE) model of the Chinese economy. The baseline scenario for the Chinese economy over the period to 2010 is first developed under a set of assumptions

  2. Evaluation of a 99Tcm bound brain scanning agent for single photon emission computed tomography

    DEFF Research Database (Denmark)

    Andersen, A R; Hasselbalch, S G; Paulson, O B

    1986-01-01

    D,L HM-PAO-99Tcm (PAO) is a lipophilic tracer complex which is avidly taken up by the brain. We have compared the regional distribution of PAO with regional cerebral blood flow (CBF). CBF was measured by single photon emission computed tomography (SPECT) by Tomomatic 64 after 133Xe inhalation in 41...

  3. Single photon emission computed tomography in motor neuron disease with dementia

    Energy Technology Data Exchange (ETDEWEB)

    Sawada, H.; Udaka, F.; Kishi, Y.; Seriu, N.; Ohtani, S.; Abe, K.; Mezaki, T.; Kameyama, M.; Honda, M.; Tomonobu, M.

    1988-12-01

    Single photon emission computed tomography with (123 I) isopropylamphetamine was carried out on a patient with motor neutron disease with dementia. (123 I) uptake was decreased in the frontal lobes. This would reflect the histopathological findings such as neuronal loss and gliosis in the frontal lobes.

  4. Single photon emission computed tomography in motor neuron disease with dementia.

    Science.gov (United States)

    Sawada, H; Udaka, F; Kishi, Y; Seriu, N; Mezaki, T; Kameyama, M; Honda, M; Tomonobu, M

    1988-01-01

    Single photon emission computed tomography with [123 I] isopropylamphetamine was carried out on a patient with motor neuron disease with dementia. [123 I] uptake was decreased in the frontal lobes. This would reflect the histopathological findings such as neuronal loss and gliosis in the frontal lobes.

  5. Fluorine-18 fluorodeoxyglucose positron emission tomography-computed tomography in evaluation of residual intramuscular myxoma

    International Nuclear Information System (INIS)

    Zade, Anand; Ahire, Archana; Shetty, Shishir; Rai, Sujith; Bokka, Rajashekharrao; Velumani, Arokiaswamy; Kabnurkar, Rasika

    2015-01-01

    Intramuscular myxoma (IM) is a rare benign neoplasm. In a patient diagnosed with IM of left thigh, we report the utility of a postoperative fluorine-18 fluorodeoxyglucose positron emission tomography-computed tomography scan in assessing the efficacy of surgical excision

  6. The contribution of single photon emission computed tomography in the clinical assessment of Alzheimer type dementia

    International Nuclear Information System (INIS)

    Boudousq, V.; Collombier, L.; Kotzki, P.O.

    1999-01-01

    Interest of brain single-photon emission computed tomography to support clinical diagnosis of Alzheimer-type dementia is now established. Numerous studies have reported a decreased perfusion in the association cortex of the parietal lobe and the posterior temporal regions. In patients with mild cognitive complaints, the presence of focal hypoperfusion may increase substantially the probability of the disease. In addition, emission tomography emerges as a helpful tool in situation in which there is diagnostic doubt. In this case, the presence of temporo-parietal perfusion deficit associated with hippocampal atrophy on MRI or X-ray computed tomography contributes to diagnostic accuracy. However, some studies suggest that emission tomography may be useful for preclinical prediction of Alzheimer's disease and to predict cognitive decline. (author)

  7. Solving Multi-Pollutant Emission Dispatch Problem Using Computational Intelligence Technique

    Directory of Open Access Journals (Sweden)

    Nur Azzammudin Rahmat

    2016-06-01

    Full Text Available Economic dispatch is a crucial process conducted by the utilities to correctly determine the satisfying amount of power to be generated and distributed to the consumers. During the process, the utilities also consider pollutant emission as the consequences of fossil-fuel consumption. Fossil-fuel includes petroleum, coal, and natural gas; each has its unique chemical composition of pollutants i.e. sulphur oxides (SOX, nitrogen oxides (NOX and carbon oxides (COX. This paper presents multi-pollutant emission dispatch problem using computational intelligence technique. In this study, a novel emission dispatch technique is formulated to determine the amount of the pollutant level. It utilizes a pre-developed optimization technique termed as differential evolution immunized ant colony optimization (DEIANT for the emission dispatch problem. The optimization results indicated high level of COX level, regardless of any type of fossil fuel consumed.

  8. USER'S GUIDE TO THE PERSONAL COMPUTER VERSION OF THE BIOGENIC EMISSIONS INVENTORY SYSTEM (PC-BEIS2)

    Science.gov (United States)

    The document is a user's guide for an updated Personal Computer version of the Biogenic Emissions Inventory System (PC-BEIS2), allowing users to estimate hourly emissions of biogenic volatile organic compounds (BVOCs) and soil nitrogen oxide emissions for any county in the contig...

  9. Atmospheric emissivity with clear sky computed by E-Trans/HITRAN

    Science.gov (United States)

    Mendoza, Víctor M.; Villanueva, Elba E.; Garduño, René; Sánchez-Meneses, Oscar

    2017-04-01

    The vertical profiles of temperature and pressure from the International Standard Atmosphere, together with the mixing ratio profiles of the main greenhouse effect gases (GG), namely water vapour, CO2 , CH4 , N2 O and stratospheric O3 , are used to determine the downward emissivity of long wave radiation by cloudless atmosphere, by means of the spectral calculator E-Trans with the HITRAN (high-resolution transmission) database. We make a review of emissivity parameterizations, reported by several authors, in terms of the surface vapour pressure and surface air temperature. We compute vertically weighted averages of temperature and pressure, also parameterize the CH4 , N2 O and O3 mixing ratio profiles, in order to adapt these variables as required by the E-Trans/HITRAN. Our results of emissivity for the corresponding vapour pressures agree well with those obtained by the reviewed authors. With this method, the emissivity can be computed at a regional scale and towards the future global warming, according to the IPCC temperature projections that will also increase the atmospheric humidity, from the emission scenarios of GG.

  10. The computation of carbon emissions due to the net payload on a truck

    DEFF Research Database (Denmark)

    Turkensteen, Marcel

    , it is necessary to compute the carbon emissions of these decisions. Current studies are only able to determine this for very specific conditions, such as a given vehicle under given driving conditions, and they may require many input parameters. Therefore, this paper presents a simple and broadly applicable...... values can then be used to evaluate the carbon emission savings of many decisions related to the load on the vehicle, e.g., the decision to drive less frequently but with more load on the vehicle....

  11. Computed tomography angiography and perfusion to assess coronary artery stenosis causing perfusion defects by single photon emission computed tomography

    DEFF Research Database (Denmark)

    Rochitte, Carlos E; George, Richard T; Chen, Marcus Y

    2014-01-01

    AIMS: To evaluate the diagnostic power of integrating the results of computed tomography angiography (CTA) and CT myocardial perfusion (CTP) to identify coronary artery disease (CAD) defined as a flow limiting coronary artery stenosis causing a perfusion defect by single photon emission computed...... tomography (SPECT). METHODS AND RESULTS: We conducted a multicentre study to evaluate the accuracy of integrated CTA-CTP for the identification of patients with flow-limiting CAD defined by ≥50% stenosis by invasive coronary angiography (ICA) with a corresponding perfusion deficit on stress single photon...... myocardial infarction, the AUC was 0.90 (95% CI: 0.87-0.94) and in patients without prior CAD the AUC for combined CTA-CTP was 0.93 (95% CI: 0.89-0.97). For the combination of a CTA stenosis ≥50% stenosis and a CTP perfusion deficit, the sensitivity, specificity, positive predictive, and negative predicative...

  12. LERFCM: a computer code for spatial reconstruction of volume emission from chord measurements in plasmas

    International Nuclear Information System (INIS)

    Navarro, A.P.; Pare, V.K.; Dunlap, J.L.

    1981-01-01

    Local Emissivity Reconstruction from Chord Measurements (LERFCM) is a package of computer programs used to determine the two-dimensional spatial distribution of the emission intensity of radiation in a plasma from line integral data, which represents signals from arrays of collimated detectors looking through the plasma along different chords in a plane. The method requires data from only a few detector arrays and assumes that the emission distribution in the plane of observation has a smooth angular dependence that can be represented by a few low-order harmonics. The intended application is a reconstruction of plasma shape and MHD instabilities, using data from arrays of soft x-ray detectors on Impurity Study Experiment Tokamak

  13. Degenerative dementia: nosological aspects and results of single photon emission computed tomography

    International Nuclear Information System (INIS)

    Dubois, B.; Habert, M.O.

    1999-01-01

    Ten years ago, the diagnosis discussion of a dementia case for the old patient was limited to two pathologies: the Alzheimer illness and the Pick illness. During these last years, the frame of these primary degenerative dementia has fallen into pieces. The different diseases and the results got with single photon emission computed tomography are discussed. for example: fronto-temporal dementia, primary progressive aphasia, progressive apraxia, visio-spatial dysfunction, dementia at Lewy's bodies, or cortico-basal degeneration. (N.C.)

  14. 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography in Tuberculosis: Spectrum of Manifestations.

    Science.gov (United States)

    Agarwal, Krishan Kant; Behera, Abhishek; Kumar, Rakesh; Bal, Chandrasekhar

    2017-01-01

    The objective of this article is to provide an illustrative tutorial highlighting the utility of 18 F-fluorodeoxyglucose-positron emission tomography/computed tomography ( 18 F-FDG-PET/CT) imaging to detect spectrum of manifestations in patients with tuberculosis (TB). FDG-PET/CT is a powerful tool for early diagnosis, measuring the extent of disease (staging), and consequently for evaluation of response to therapy in patients with TB.

  15. Noninvasive measurement of regional myocardial glucose metabolism by positron emission computed tomography. [Dogs

    Energy Technology Data Exchange (ETDEWEB)

    Schelbert, H.R.; Phelps, M.E.

    1980-06-01

    While the results of regional myocardial glucose metabolism measurements using positron emission computed tomography (/sup 13/N-ammonia) are promising, their utility and value remains to be determined in man. If this technique can be applied to patients with acute myocardial ischemia or infarction it may permit delineation of regional myocardial segments with altered, yet still active metabolism. Further, it may become possible to evaluate the effects of interventions designed to salvage reversibly injured myocardium by this technique.

  16. Evaluation of a 99Tcm bound brain scanning agent for single photon emission computed tomography

    DEFF Research Database (Denmark)

    Andersen, A R; Hasselbalch, S G; Paulson, O B

    1986-01-01

    D,L HM-PAO-99Tcm (PAO) is a lipophilic tracer complex which is avidly taken up by the brain. We have compared the regional distribution of PAO with regional cerebral blood flow (CBF). CBF was measured by single photon emission computed tomography (SPECT) by Tomomatic 64 after 133Xe inhalation in ...... of the (decay corrected) brain counts were lost during 24 hours....

  17. Computation of uncertainty for atmospheric emission projections from key pollutant sources in Spain

    Science.gov (United States)

    Lumbreras, Julio; García-Martos, Carolina; Mira, José; Borge, Rafael

    Emission projections are important for environmental policy, both to evaluate the effectiveness of abatement strategies and to determine legislation compliance in the future. Moreover, including uncertainty is an essential added value for decision makers. In this work, projection values and their associated uncertainty are computed for pollutant emissions corresponding to the most significant activities from the national atmospheric emission inventory in Spain. Till now, projections had been calculated under three main scenarios: "without measures" (WoM), "with measures" (WM) and "with additional measures" (WAM). For the first one, regression techniques had been applied, which are inadequate for time-dependent data. For the other scenarios, values had been computed taking into account expected activity growth, as well as policies and measures. However, only point forecasts had been computed. In this work statistical methodology has been applied for: a) Inclusion of projection intervals for future time points, where the width of the intervals is a measure of uncertainty. b) For the WoM scenario, ARIMA models are applied to model the dynamics of the processes. c) In the WM scenario, bootstrap is applied as an additional non-parametric tool, which does not rely on distributional assumptions and is thus more general. The advantages of using ARIMA models for the WoM scenario including uncertainty are shown. Moreover, presenting the WM scenario allows observing if projected emission values fall within the intervals, thus showing if the measures to be taken to reach the scenario imply a significant improvement. Results also show how bootstrap techniques incorporate stochastic modelling to produce forecast intervals for the WM scenario.

  18. Optimization methods of the net emission computation applied to cylindrical sodium vapor plasma

    International Nuclear Information System (INIS)

    Hadj Salah, S.; Hajji, S.; Ben Hamida, M. B.; Charrada, K.

    2015-01-01

    An optimization method based on a physical analysis of the temperature profile and different terms in the radiative transfer equation is developed to reduce the time computation of the net emission. This method has been applied for the cylindrical discharge in sodium vapor. Numerical results show a relative error of spectral flux density values lower than 5% with an exact solution, whereas the computation time is about 10 orders of magnitude less. This method is followed by a spectral method based on the rearrangement of the lines profile. Results are shown for Lorentzian profile and they demonstrated a relative error lower than 10% with the reference method and gain in computation time about 20 orders of magnitude

  19. Comparison of adenosine and treadmill exercise thallium-201 stress tests for the detection of coronary artery disease

    International Nuclear Information System (INIS)

    Abe, Shinya; Takeishi, Yasuchika; Chiba, Junya; Ikeda, Kozue; Tomoike, Hitonobu

    1993-01-01

    To determine the clinical usefulness of adenosine Tl-201 imaging for the evaluation of coronary artery disease, 22 patients with suspected coronary artery disease who underwent adenosine and exercise Tl-201 single photon emission computed tomography (SPECT) were studied. The peak levels of heart rate (83 vs 123 bpm, p<0.001), systolic blood pressure (124 vs 164 mmHg, p<0.001), diastolic blood pressure (70 vs 86 mmHg, p<0.01) and rate pressure products (10220 vs 20410 bpm x mmHg, p<0.001) were markedly smaller during adenosine infusion than during exercise. Segmental agreements between adenosine and exercise tests were 90% (218 of 242 segments) regarding the presence of perfusion defects and 89% (215 of 242 segments) regarding the presence of redistribution. Regional Tl-201 uptake (r=0.85, p<0.001) and the extent (r=0.75, p<0.001) and intensity (r=0.83, p<0.001) of Tl-201 defects during adenosine testing were closely correlated with those of exercise testing. Adenosine and exercise tests showed similar sensitivities for the identification of individual coronary stenosis (85% vs 78%). However, in patients who were unable to perform adequate exercise (maximal heart rate<120 bpm), the sensitivity of adenosine imaging tended to be higher than that of exercise imaging (92% vs 69%, p=0.07). Adenosine Tl-201 imaging is an alternative to the exercise test for assessing the severity and loci of coronary artery disease, especially in patients who are unable to perform adequate physical exercise. (author)

  20. Occult primary tumors of the head and neck: accuracy of thallium 201 single-photon emission computed tomography and computed tomography and/or magnetic resonance imaging

    NARCIS (Netherlands)

    van Veen, S. A.; Balm, A. J.; Valdés Olmos, R. A.; Hoefnagel, C. A.; Hilgers, F. J.; Tan, I. B.; Pameijer, F. A.

    2001-01-01

    To determine the accuracy of thallium 201 single-photon emission computed tomography (thallium SPECT) and computed tomography and/or magnetic resonance imaging (CT/MRI) in the detection of occult primary tumors of the head and neck. Study of diagnostic tests. National Cancer Institute, Amsterdam,

  1. Comparing embodied greenhouse gas emissions of modern computing and electronics products.

    Science.gov (United States)

    Teehan, Paul; Kandlikar, Milind

    2013-05-07

    Information and communications technology (ICT) contributes substantially to global greenhouse gas (GHG) pollutant emissions, but it is time-consuming to estimate the environmental impacts caused by the production of ICT devices, and the literature lacks coverage for newer products. Using a process-sum life cycle assessment (LCA) approach, we estimate and compare the embodied GHG emissions of 11 ICT products, including large- and small-form-factor desktop and laptop personal computers, a thin client device, an LCD monitor, newer mobile devices (an Apple iPad, an iPod Touch, and an Amazon Kindle), a rack server, and a network switch. Full bills of materials are provided via hand disassembly and weighing and are mapped to processes in the ecoinvent v2.2 database to produce impact estimates. Results are analyzed to develop simplified impact estimation models using linear regressions based on product characteristics. A simple and robust linear relationship between mass and embodied emissions is identified; a more sophisticated linear model using display mass, battery mass, and circuit board mass as inputs is slightly more accurate. Embodied GHG emissions for newer products are 50-60% lower than corresponding older products with similar functionality, largely due to decreased material usage, especially reductions in integrated circuit content.

  2. Acute Calculous Cholecystitis Missed on Computed Tomography and Ultrasound but Diagnosed with Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

    Directory of Open Access Journals (Sweden)

    Carina Mari Aparici

    2016-01-01

    Full Text Available We present a case of a 69-year-old patient who underwent ascending aortic aneurysm repair with aortic valve replacement. On postsurgical day 12, he developed leukocytosis and low-grade fevers. The chest computed tomography (CT showed a periaortic hematoma which represents a postsurgical change from aortic aneurysm repair, and a small pericardial effusion. The abdominal ultrasound showed cholelithiasis without any sign of cholecystitis. Finally, a fluorodeoxyglucose (FDG-positron emission tomography (PET/CT examination was ordered to find the cause of fever of unknown origin, and it showed increased FDG uptake in the gallbladder wall, with no uptake in the lumen. FDG-PET/CT can diagnose acute cholecystitis in patients with nonspecific clinical symptoms and laboratory results.

  3. Computer Reconstruction of Plant Growth and Chlorophyll Fluorescence Emission in Three Spatial Dimensions

    Science.gov (United States)

    Bellasio, Chandra; Olejníčková, Julie; Tesař, Radek; Šebela, David; Nedbal, Ladislav

    2012-01-01

    Plant leaves grow and change their orientation as well their emission of chlorophyll fluorescence in time. All these dynamic plant properties can be semi-automatically monitored by a 3D imaging system that generates plant models by the method of coded light illumination, fluorescence imaging and computer 3D reconstruction. Here, we describe the essentials of the method, as well as the system hardware. We show that the technique can reconstruct, with a high fidelity, the leaf size, the leaf angle and the plant height. The method fails with wilted plants when leaves overlap obscuring their true area. This effect, naturally, also interferes when the method is applied to measure plant growth under water stress. The method is, however, very potent in capturing the plant dynamics under mild stress and without stress. The 3D reconstruction is also highly effective in correcting geometrical factors that distort measurements of chlorophyll fluorescence emission of naturally positioned plant leaves. PMID:22368511

  4. Role of isotope scan, including positron emission tomography/computed tomography, in nodular goitre.

    Science.gov (United States)

    Giovanella, Luca; Ceriani, Luca; Treglia, Giorgio

    2014-08-01

    Nuclear medicine techniques were first used in clinical practice for diagnosing and treating thyroid diseases in the 1950s, and are still an integral part of thyroid nodules work-up. Thyroid imaging with iodine or iodine-analogue isotopes is the only examination able to prove the presence of autonomously functioning thyroid tissue, which excludes malignancy with a high probability. In addition, a thyroid scan with technetium-99m-methoxyisobutylisonitrile is able to avoid unnecessary surgical procedures for cytologically inconclusive thyroid nodules, as confirmed by meta-analysis and cost-effectiveness studies. Finally, positron emission tomography alone, and positron emission tomography combined with computed tomography scans with (18)F-fluoro-2-deoxy-d-glucose are also promising for diagnosing thyroid diseases, but further studies are needed before introducing them to clinical practice. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Brain receptor single-photon emission computer tomography with 123I Datscan in Parkinson's disease

    International Nuclear Information System (INIS)

    Minchev, D.; Peshev, N.; Kostadinova, I.; Grigorova, O.; Trindev, P.; Shotekov, P.

    2005-01-01

    Clinical aspects of Parkinson's disease are not enough for the early diagnosis of the disease. Positron emission tomography and the receptor single - photon emission tomography can be used for imaging functional integrity of nigrostriatal dopaminergic structures. 24 patient (17 men and 7 women) were investigated. 20 of them are with Parkinson's disease and 4 are with essential tremor. The radiopharmaceutical - 123I-Datscan (ioflupane, bind with 123I) represent a cocaine analogue with selective affinity to dopamine transporters, located in the dopaminergic nigrostriatal terminals in the striatum. Single - photon emission computer tomography was performed with SPECT gamma camera (ADAC, SH Epic detector). The scintigraphic study was made 3 to 6 hours after intravenous injection of the radiopharmaceutical - 123I- Datscan in dose 185 MBq. 120 frames are registered with duration of each one 22 seconds and gamma camera rotation 360. After generation of transversal slices we generated two composites pictures. The first composite picture image the striatum, the second - the occipital region. Two ratios were calculated representing the uptake of the radiopharmaceutical in the left and right striatum. Qualitative and quantitative criteria were elaborated for evaluating the scintigraphic patterns. Decreased, nonhomogeneous and asymmetric uptake of the radiopharmaceutical coupled with low quantitative parameters in range from 1.44 to 2.87 represents the characteristic scintigraphic pattern for Parkinson's disease with clear clinical picture. Homogenous with high intensity and symmetric uptake of the radiopharmaceutical in the striatum coupled with his clear frontier and with quantitative parameters up to 4.40 represent the scintigraphic pattern in two patients with essential tremor. Receptor single - photon emission computer tomography with 123I - Datscan represents an accurate nuclear-medicine method for precise diagnosis of Parkinson's disease and for its differentiation from

  6. Fluorodeoxyglucose positron emission tomography-computed tomography findings in a case of xanthogranulomatous pyelonephritis

    Science.gov (United States)

    Joshi, Prathamesh; Lele, Vikram; Shah, Hardik

    2013-01-01

    Xanthogranulomatous pyelonephritis (XGNP) is an uncommon condition characterized by chronic suppurative renal inflammation that leads to progressive parenchymal destruction. This condition can clinically present as recurrent urinary tract infections, flank pain, hematuria, and occasionally sepsis, and weight loss. This condition is usually associated with obstructing renal calculus. We present 18-fluorodeoxyglucose positron emission tomography-computed tomography (18-FDG PET/CT) findings in an elderly male suffering from pyrexia and weight loss and suspected urinary tract infection. PET/CT findings in this case lead to diagnosis of XGNP. This diagnosis should be kept in mind while evaluating similar symptoms and PET/CT scan findings. PMID:24019680

  7. Image reconstruction using three-dimensional compound Gauss-Markov random field in emission computed tomography

    International Nuclear Information System (INIS)

    Watanabe, Shuichi; Kudo, Hiroyuki; Saito, Tsuneo

    1993-01-01

    In this paper, we propose a new reconstruction algorithm based on MAP (maximum a posteriori probability) estimation principle for emission tomography. To improve noise suppression properties of the conventional ML-EM (maximum likelihood expectation maximization) algorithm, direct three-dimensional reconstruction that utilizes intensity correlations between adjacent transaxial slices is introduced. Moreover, to avoid oversmoothing of edges, a priori knowledge of RI (radioisotope) distribution is represented by using a doubly-stochastic image model called the compound Gauss-Markov random field. The a posteriori probability is maximized by using the iterative GEM (generalized EM) algorithm. Computer simulation results are shown to demonstrate validity of the proposed algorithm. (author)

  8. The display of multiple images derived from emission computed assisted tomography (ECAT)

    International Nuclear Information System (INIS)

    Jackson, P.C.; Davies, E.R.; Goddard, P.R.; Wilde, R.P.H.

    1983-01-01

    In emission computed assisted tomography, a technique has been developed to display the multiple sections of an organ within a single image, such that three dimensional appreciation of the organ can be obtained, whilst also preserving functional information. The technique when tested on phantoms showed no obvious deterioration in resolution and when used clinically gave satisfactory visual results. Such a method should allow easier appreciation of the extent of a lesion through an organ and thus allow dimensions to be obtained by direct measurement. (U.K.)

  9. Bronchobiliary Fistula Localized by Cholescintigraphy with Single-Photon Emission Computed Tomography

    International Nuclear Information System (INIS)

    Artunduaga, Maddy; Patel, Niraj R.; Wendt, Julie A.; Guy, Elizabeth S.; Nachiappan, Arun C.

    2015-01-01

    Biliptysis is an important clinical feature to recognize as it is associated with bronchobiliary fistula, a rare entity. Bronchobiliary fistulas have been diagnosed with planar cholescintigraphy. However, cholescintigraphy with single-photon emission computed tomography (SPECT) can better spatially localize a bronchobiliary fistula as compared to planar cholescintigraphy alone, and is useful for preoperative planning if surgical treatment is required. Here, we present the case of a 23-year-old male who developed a bronchobiliary fistula in the setting of posttraumatic and postsurgical infection, which was diagnosed and localized by cholescintigraphy with SPECT

  10. Painful spondylolysis or spondylolisthesis studied by radiography and single-photon emission computed tomography

    International Nuclear Information System (INIS)

    Collier, B.D.; Johnson, R.P.; Carrera, G.F.

    1985-01-01

    Planar bone scintigraphy (PBS) and single-photon emission computed tomography (SPECT) were compared in 19 adults with radiographic evidence of spondylolysis and/or spondylolisthesis. SPECT was more sensitive than PBS when used to identify symptomatic patients and sites of painful defects in the pars interarticularis. In addition, SPECT allowed more accurate localization than PBS. In 6 patients, spondylolysis or spondylolisthesis was unrealted to low back pain, and SPECT images of the posterior neural arch were normal. The authors conclude that when spondylolysis or spondylolisthesis is the cause of low back pain, pars defects are frequently heralded by increased scintigraphic activity which is best detected and localized by SPECT

  11. Painful spondylolysis or spondylolisthesis studied by radiography and single-photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Collier, B.D.; Johnson, R.P.; Carrera, G.F.; Meyer, G.A.; Schwab, J.P.; Flatley, T.J.; Isitman, A.T.; Hellman, R.S.; Zielonka, J.S.; Knobel, J.

    1985-01-01

    Planar bone scintigraphy (PBS) and single-photon emission computed tomography (SPECT) were compared in 19 adults with radiographic evidence of spondylolysis and/or spondylolisthesis. SPECT was more sensitive than PBS when used to identify symptomatic patients and sites of painful defects in the pars interarticularis. In addition, SPECT allowed more accurate localization than PBS. In 6 patients, spondylolysis or spondylolisthesis was unrealted to low back pain, and SPECT images of the posterior neural arch were normal. The authors conclude that when spondylolysis or spondylolisthesis is the cause of low back pain, pars defects are frequently heralded by increased scintigraphic activity which is best detected and localized by SPECT.

  12. The role of (18)fluoro-deoxyglucose positron emission tomography/computed tomography in resectable pancreatic cancer.

    Science.gov (United States)

    Crippa, Stefano; Salgarello, Matteo; Laiti, Silvia; Partelli, Stefano; Castelli, Paola; Spinelli, Antonello E; Tamburrino, Domenico; Zamboni, Giuseppe; Falconi, Massimo

    2014-08-01

    The role of (18)fluoro-deoxyglucose positron emission tomography/computed tomography in pancreatic ductal adenocarcinoma is debated. We retrospectively assessed the value of (18)fluoro-deoxyglucose positron emission tomography/computed tomography in addition to conventional imaging as a staging modality in pancreatic cancer. (18)Fluoro-deoxyglucose positron emission tomography/computed tomography was performed in 72 patients with resectable pancreatic carcinoma after multi-detector computed tomography positron emission tomography was considered positive for a maximum standardized uptake value >3. Overall, 21% of patients had a maximum standardized uptake value ≤ 3, and 60% of those had undergone neoadjuvant treatment (P=0.0001). Furthermore, 11% of patients were spared unwarranted surgery since positron emission tomography/computed tomography detected metastatic disease. All liver metastases were subsequently identified with contrast-enhanced ultrasound. Sensitivity and specificity of positron emission tomography/computed tomography for distant metastases were 78% and 100%. The median CA19.9 concentration was 48.8 U/mL for the entire cohort and 292 U/mL for metastatic patients (P=0.112). The widespread application of (18)fluoro-deoxyglucose positron emission tomography/computed tomography in patients with resectable pancreatic carcinoma seems not justified. It should be considered in selected patients at higher risk of metastatic disease (i.e. CA19.9>200 U/mL) after undergoing other imaging tests. Neoadjuvant treatment is significantly associated with low metabolic activity, limiting the value of positron emission tomography in this setting. Copyright © 2014 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  13. The diagnostic value of single-photon emission computed tomography/computed tomography for severe sacroiliac joint dysfunction.

    Science.gov (United States)

    Tofuku, Katsuhiro; Koga, Hiroaki; Komiya, Setsuro

    2015-04-01

    We aimed to evaluate the value of single-photon emission computed tomography (SPECT)/computed tomography (CT) for the diagnosis of sacroiliac joint (SIJ) dysfunction. SPECT/CT was performed in 32 patients with severe SIJ dysfunction, who did not respond to 1-year conservative treatment and had a score of >4 points on a 10-cm visual analog scale. We investigated the relationship between the presence of severe SIJ dysfunction and tracer accumulation, as confirmed by SPECT/CT. In cases of bilateral SIJ dysfunction, we also compared the intensity of tracer accumulation on each side. Moreover, we examined the relationship between the intensity of tracer accumulation and the different treatments the patients subsequently received. All 32 patients with severe SIJ dysfunction had tracer accumulation with a standardized uptake value (SUV) of >2.2 (mean SUV 4.7). In the 19 patients with lateralized symptom intensity, mean SUVs of the dominant side were significantly higher than those of the nondominant side. In 10 patients with no lateralization, the difference in the SUVs between sides was tracer accumulation required more advanced treatment. Patients with higher levels of tracer accumulation had greater symptom severity and also required more advanced treatment. Thus, we believe that SPECT/CT may be a suitable supplementary diagnostic modality for SIJ dysfunction as well as a useful technique for predicting the prognosis of this condition.

  14. Whole body positron emission tomography/computed tomography staging of metastatic choroidal melanoma.

    Science.gov (United States)

    Kurli, Madhavi; Reddy, Shantan; Tena, Lawrence B; Pavlick, Anna C; Finger, Paul T

    2005-08-01

    To evaluate whole-body positron emission tomography (PET)/computed tomography in staging of patients with metastatic choroidal melanoma. Interventional non-randomized clinical study. Twenty patients were referred for whole-body 18-fluoro-2-deoxy-D-glucose (FDG) PET/computed tomography imaging because of suspected metastatic choroidal melanoma. PET/computed tomography images were studied for the presence and distribution of metastatic melanoma. Subsequent biopsies were performed to confirm the presence of metastatic disease. Twenty patients underwent PET/computed tomography. Eighteen were imaged because of abnormal clinical, hematologic, or radiographic screening studies during the course of their follow-up after plaque brachytherapy or enucleation. Two were imaged before treatment of their primary tumor. PET/computed tomography revealed or confirmed metastatic melanoma in eight (40%) of these 20 patients. The mean time from initial diagnosis to metastasis was 47 months (range 0 to 154). The most common sites for metastases were the liver (100%), bone (50%), lung (25%), lymph nodes (25%), and subcutaneous tissue (25%). Cardiac, brain, thyroid, and posterior abdominal wall lesions (12.5%) were also noted. Six patients (75%) had multiple organ involvement. No false positives were noted. PET/computed tomography imaging also detected benign lesions of the bone and lymph nodes in three patients (15%). All patients had hepatic metastases and liver enzyme assays were abnormal in only one (12.5%) of eight patients. PET/computed tomography imaging is a sensitive tool for the detection and localization of hepatic and extra-hepatic (particularly osseous) metastatic choroidal melanoma.

  15. Single-photon emission computed tomography in human immunodeficiency virus encephalopathy: A preliminary report

    International Nuclear Information System (INIS)

    Masdeu, J.C.; Yudd, A.; Van Heertum, R.L.; Grundman, M.; Hriso, E.; O'Connell, R.A.; Luck, D.; Camli, U.; King, L.N.

    1991-01-01

    Depression or psychosis in a previously asymptomatic individual infected with the human immunodeficiency virus (HIV) may be psychogenic, related to brain involvement by the HIV or both. Although prognosis and treatment differ depending on etiology, computed tomography (CT) and magnetic resonance imaging (MRI) are usually unrevealing in early HIV encephalopathy and therefore cannot differentiate it from psychogenic conditions. Thirty of 32 patients (94%) with HIV encephalopathy had single-photon emission computed tomography (SPECT) findings that differed from the findings in 15 patients with non-HIV psychoses and 6 controls. SPECT showed multifocal cortical and subcortical areas of hypoperfusion. In 4 cases, cognitive improvement after 6-8 weeks of zidovudine (AZT) therapy was reflected in amelioration of SPECT findings. CT remained unchanged. SPECT may be a useful technique for the evaluation of HIV encephalopathy

  16. Effect of oral contrast agents on computed tomography-based positron emission tomography attenuation correction in dual-modality positron emission tomography/computed tomography imaging.

    Science.gov (United States)

    Antoch, Gerald; Jentzen, Walter; Freudenberg, Lutz S; Stattaus, Jorg; Mueller, Stefan P; Debatin, Jorg F; Bockisch, Andreas

    2003-12-01

    To evaluate the effect of iodine- and barium-based contrast agents on the computed tomography (CT)-based positron emission tomography (PET) attenuation correction in dual-modality PET/CT. Experiments were conducted on a Society of Nuclear Medicine/National Electrical Manufacturers Association-PET phantom equipped with cylinders containing [18F]-2-fluoro-2-desoxy-D-glucose. The main compartment was filled with iodine (0.5-10%), barium (0.5-50%), or water (negative control). The error in attenuation correction was determined by comparison of measured tracer quantities in the presence of contrast agents with expected quantities. Contrast agent attenuation was demonstrated to be comparable to in vivo conditions. The presence of contrast agents resulted in an overestimation of the intracylindrical activity concentration on PET images and overestimation directly related to contrast concentrations (iodine 5-38%; barium 15-580%). Iodine and barium concentrations in clinical use resulted in an activity overestimation of 20 +/- 1.8% for iodine and 21 +/- 2.9% for barium. An overestimation of the tracer activity concentration is to be expected in the presence of oral contrast agents, if PET attenuation correction is attained CT-based.

  17. Clean air, clear market. Making emissions trading work: The role of a computer-assisted auction

    International Nuclear Information System (INIS)

    Bartels, C.W.; Marron, D.B.; Lipsky, M.I.

    1993-01-01

    Creating a new commodity presents the chance to develop new markets in which to trade it. In many cases, existing markets can be adapted easily; in other cases it proves worthwhile to develop new forms that reflect special characteristics of the commodity and those who trade it. In the case of the sulfur dioxide (SO 2 ) emission allowances created by the Clean Air Act Amendments of 1990, a number of standard market forms already have been adopted. While these will prove useful for handling some transactions, a new Market Clearing Auction (MCA) offers buyers and sellers a centralized marketplace for trading SO 2 emission allowances. The MCA, which was developed by the brokerage firm Cantor Fitzgerald, is a computer-assisted open-quotes smartclose quotes auction designed to replicate the outcome of an efficient market in emission allowances, and accepts bids and offers for any possible combination of allowances. Orders can be submitted for streams of allowances. Orders can be submitted for streams of allowances covering more than one year. The auction then determines the combination of bids and offers that maximizes the gains from trades in the market, and establishes uniform market clearing prices for each allowance issue (1995, 1996, and so on). Once executed, trades are settled on a cash-forward basis; that is, allowances are delivered and payments are made at future dates

  18. A computational study of particulate emissions from an open pit quarry under neutral atmospheric conditions

    Science.gov (United States)

    Silvester, S. A.; Lowndes, I. S.; Hargreaves, D. M.

    2009-12-01

    The extraction of minerals from surface mines and quarries can produce significant fugitive dust emissions as a result of site activities such as blasting, road haulage, loading, crushing and stockpiling. If uncontrolled, these emissions can present serious environmental, health, safety and operational issues impacting both site personnel and the wider community. The dispersion of pollutant emissions within the atmosphere is principally determined by the background wind systems characterized by the atmospheric boundary layer (ABL). This paper presents an overview of the construction and solution of a computational fluid dynamics (CFD) model to replicate the development of the internal ventilation regime within a surface quarry excavation due to the presence of a neutral ABL above this excavation. This model was then used to study the dispersion and deposition of fugitive mineral dust particles generated during rock blasting operations. The paths of the mineral particles were modelled using Lagrangian particle tracking. Particles of four size fractions were released from five blast locations for eight different wind directions. The study concluded that dependent on the location of the bench blast within the quarry and the direction of the wind, a mass fraction of between 0.3 and 0.6 of the emitted mineral particles was retained within the quarry. The retention was largest when the distance from the blast location to the downwind pit boundary was greatest.

  19. Stimulated Emission Computed Tomography (NSECT) images enhancement using a linear filter in the frequency domain

    International Nuclear Information System (INIS)

    Viana, Rodrigo S.S.; Tardelli, Tiago C.; Yoriyaz, Helio; Jackowski, Marcel P.

    2011-01-01

    In recent years, a new technique for in vivo spectrographic imaging of stable isotopes was presented as Neutron Stimulated Emission Computed Tomography (NSECT). In this technique, a fast neutrons beam stimulates stable nuclei in a sample, which emit characteristic gamma radiation. The photon energy is unique and is used to identify the emitting nuclei. The emitted gamma energy spectra can be used for reconstruction of the target tissue image and for determination of the tissue elemental composition. Due to the stochastic nature of photon emission process by irradiated tissue, one of the most suitable algorithms for tomographic reconstruction is the Expectation-Maximization (E-M) algorithm, once on its formulation are considered simultaneously the probabilities of photons emission and detection. However, a disadvantage of this algorithm is the introduction of noise in the reconstructed image as the number of iterations increases. This increase can be caused either by features of the algorithm itself or by the low sampling rate of projections used for tomographic reconstruction. In this work, a linear filter in the frequency domain was used in order to improve the quality of the reconstructed images. (author)

  20. Stimulated Emission Computed Tomography (NSECT) images enhancement using a linear filter in the frequency domain

    Energy Technology Data Exchange (ETDEWEB)

    Viana, Rodrigo S.S.; Tardelli, Tiago C.; Yoriyaz, Helio, E-mail: hyoriyaz@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Jackowski, Marcel P., E-mail: mjack@ime.usp.b [University of Sao Paulo (USP), SP (Brazil). Dept. of Computer Science

    2011-07-01

    In recent years, a new technique for in vivo spectrographic imaging of stable isotopes was presented as Neutron Stimulated Emission Computed Tomography (NSECT). In this technique, a fast neutrons beam stimulates stable nuclei in a sample, which emit characteristic gamma radiation. The photon energy is unique and is used to identify the emitting nuclei. The emitted gamma energy spectra can be used for reconstruction of the target tissue image and for determination of the tissue elemental composition. Due to the stochastic nature of photon emission process by irradiated tissue, one of the most suitable algorithms for tomographic reconstruction is the Expectation-Maximization (E-M) algorithm, once on its formulation are considered simultaneously the probabilities of photons emission and detection. However, a disadvantage of this algorithm is the introduction of noise in the reconstructed image as the number of iterations increases. This increase can be caused either by features of the algorithm itself or by the low sampling rate of projections used for tomographic reconstruction. In this work, a linear filter in the frequency domain was used in order to improve the quality of the reconstructed images. (author)

  1. Efficacy of 3D-positron emission tomography/computed tomography for upper abdomen.

    Science.gov (United States)

    Murakami, Koji; Nakahara, Tadaki

    2014-04-01

    Recent advancement in computed tomography (CT) enables us to obtain high spatial resolution image and made it possible to construct extensive high-definition three-dimensional (3D) images. But a lack of contrast resolution in CT alone is still remained problem. Meanwhile, as fluorodeoxyglucose-positron emission tomography (PET) can visualize tumors in high contrast, we can create 3D images fusing the accumulation in tumors on PET/CT images. Such images can play the role of a "map of body" which makes it easy to understand the anatomical information before surgery. We also try to evaluate segmental liver function by using PET/CT fusion images. By using (11) C-methionine PET/contrast-enhanced CT, superior image quality compared to single photon emission computed tomography/CT can be obtained. CT, especially with contrast enhancement for obtaining anatomical imaging information plus PET for obtaining functional imaging information is a highly compatible combination, and adding these two types information will further increase clinical usefulness. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

  2. DE-BLURRING SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY IMAGES USING WAVELET DECOMPOSITION

    Directory of Open Access Journals (Sweden)

    Neethu M. Sasi

    2016-02-01

    Full Text Available Single photon emission computed tomography imaging is a popular nuclear medicine imaging technique which generates images by detecting radiations emitted by radioactive isotopes injected in the human body. Scattering of these emitted radiations introduces blur in this type of images. This paper proposes an image processing technique to enhance cardiac single photon emission computed tomography images by reducing the blur in the image. The algorithm works in two main stages. In the first stage a maximum likelihood estimate of the point spread function and the true image is obtained. In the second stage Lucy Richardson algorithm is applied on the selected wavelet coefficients of the true image estimate. The significant contribution of this paper is that processing of images is done in the wavelet domain. Pre-filtering is also done as a sub stage to avoid unwanted ringing effects. Real cardiac images are used for the quantitative and qualitative evaluations of the algorithm. Blur metric, peak signal to noise ratio and Tenengrad criterion are used as quantitative measures. Comparison against other existing de-blurring algorithms is also done. The simulation results indicate that the proposed method effectively reduces blur present in the image.

  3. Impact of office productivity cloud computing on energy consumption and greenhouse gas emissions.

    Science.gov (United States)

    Williams, Daniel R; Tang, Yinshan

    2013-05-07

    Cloud computing is usually regarded as being energy efficient and thus emitting less greenhouse gases (GHG) than traditional forms of computing. When the energy consumption of Microsoft's cloud computing Office 365 (O365) and traditional Office 2010 (O2010) software suites were tested and modeled, some cloud services were found to consume more energy than the traditional form. The developed model in this research took into consideration the energy consumption at the three main stages of data transmission; data center, network, and end user device. Comparable products from each suite were selected and activities were defined for each product to represent a different computing type. Microsoft provided highly confidential data for the data center stage, while the networking and user device stages were measured directly. A new measurement and software apportionment approach was defined and utilized allowing the power consumption of cloud services to be directly measured for the user device stage. Results indicated that cloud computing is more energy efficient for Excel and Outlook which consumed less energy and emitted less GHG than the standalone counterpart. The power consumption of the cloud based Outlook (8%) and Excel (17%) was lower than their traditional counterparts. However, the power consumption of the cloud version of Word was 17% higher than its traditional equivalent. A third mixed access method was also measured for Word which emitted 5% more GHG than the traditional version. It is evident that cloud computing may not provide a unified way forward to reduce energy consumption and GHG. Direct conversion from the standalone package into the cloud provision platform can now consider energy and GHG emissions at the software development and cloud service design stage using the methods described in this research.

  4. Attenuation correction in pulmonary and myocardial single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Almquist, H

    2000-01-01

    The objective was to develop and validate methods for single photon emission computed tomography, SPECT, allowing quantitative physiologic and diagnostic studies of lung and heart. A method for correction of variable attenuation in SPECT, based on transmission measurements before administration of an isotope to the subject, was developed and evaluated. A protocol based upon geometrically well defined phantoms was developed. In a mosaic pattern phantom count rates were corrected from 39-43% to 101-110% of reference. In healthy subjects non-gravitational pulmonary perfusion gradients observed without attenuation correctionwere artefacts caused by attenuation. Pulmonary density in centre of right lung, obtained from the transmission measurement, was 0.28 {+-} 0.03 g/ml in normal subjects. Mean density was lower in large lungs compared to smaller ones. We also showed that regional ventilation/perfusion ratios could be measured with SPECT, using the readily available tracer {sup 133}Xe. Because of the low energy of {sup 133}Xe this relies heavily upon attenuation correction. A commercially available system for attenuation correction with simultaneous emission and transmission, considered to improve myocardial SPECT, performed erroneously. This could lead to clinical misjudgement. We considered that manufacturer-independent pre-clinical tests are required. In a test of two other commercial systems, based on different principles, an adapted variant of our initial protocol was proven useful. Only one of the systems provided correct emission count rates independently on phantom configuration. Errors in the other system were related to inadequate compensation of the influence of emission activity on the transmission study.

  5. Attenuation correction in pulmonary and myocardial single photon emission computed tomography

    International Nuclear Information System (INIS)

    Almquist, H.

    2000-01-01

    The objective was to develop and validate methods for single photon emission computed tomography, SPECT, allowing quantitative physiologic and diagnostic studies of lung and heart. A method for correction of variable attenuation in SPECT, based on transmission measurements before administration of an isotope to the subject, was developed and evaluated. A protocol based upon geometrically well defined phantoms was developed. In a mosaic pattern phantom count rates were corrected from 39-43% to 101-110% of reference. In healthy subjects non-gravitational pulmonary perfusion gradients observed without attenuation correction were artefacts caused by attenuation. Pulmonary density in centre of right lung, obtained from the transmission measurement, was 0.28 ± 0.03 g/ml in normal subjects. Mean density was lower in large lungs compared to smaller ones. We also showed that regional ventilation/perfusion ratios could be measured with SPECT, using the readily available tracer 133 Xe. Because of the low energy of 133 Xe this relies heavily upon attenuation correction. A commercially available system for attenuation correction with simultaneous emission and transmission, considered to improve myocardial SPECT, performed erroneously. This could lead to clinical misjudgement. We considered that manufacturer-independent pre-clinical tests are required. In a test of two other commercial systems, based on different principles, an adapted variant of our initial protocol was proven useful. Only one of the systems provided correct emission count rates independently on phantom configuration. Errors in the other system were related to inadequate compensation of the influence of emission activity on the transmission study

  6. Computer simulation of energy use, greenhouse gas emissions, and process economics of the fluid milk process.

    Science.gov (United States)

    Tomasula, P M; Yee, W C F; McAloon, A J; Nutter, D W; Bonnaillie, L M

    2013-05-01

    Energy-savings measures have been implemented in fluid milk plants to lower energy costs and the energy-related carbon dioxide (CO2) emissions. Although these measures have resulted in reductions in steam, electricity, compressed air, and refrigeration use of up to 30%, a benchmarking framework is necessary to examine the implementation of process-specific measures that would lower energy use, costs, and CO2 emissions even further. In this study, using information provided by the dairy industry and equipment vendors, a customizable model of the fluid milk process was developed for use in process design software to benchmark the electrical and fuel energy consumption and CO2 emissions of current processes. It may also be used to test the feasibility of new processing concepts to lower energy and CO2 emissions with calculation of new capital and operating costs. The accuracy of the model in predicting total energy usage of the entire fluid milk process and the pasteurization step was validated using available literature and industry energy data. Computer simulation of small (40.0 million L/yr), medium (113.6 million L/yr), and large (227.1 million L/yr) processing plants predicted the carbon footprint of milk, defined as grams of CO2 equivalents (CO2e) per kilogram of packaged milk, to within 5% of the value of 96 g of CO 2e/kg of packaged milk obtained in an industry-conducted life cycle assessment and also showed, in agreement with the same study, that plant size had no effect on the carbon footprint of milk but that larger plants were more cost effective in producing milk. Analysis of the pasteurization step showed that increasing the percentage regeneration of the pasteurizer from 90 to 96% would lower its thermal energy use by almost 60% and that implementation of partial homogenization would lower electrical energy use and CO2e emissions of homogenization by 82 and 5.4%, respectively. It was also demonstrated that implementation of steps to lower non

  7. Fluorodeoxyglucose-positron emission tomography/computed tomography imaging features of colloid adenocarcinoma of the lung: a case report.

    Science.gov (United States)

    Wang, ZhenGuang; Yu, MingMing; Chen, YueHua; Kong, Yan

    2017-07-27

    Colloid adenocarcinoma of the lung is a rare subtype of variants of invasive adenocarcinomas. We report the appearance of this unusual entity on 18 F-fluorodeoxyglucose positron emission tomography/computed tomography. A 60-year-old man of Chinese Han nationality coughed with a little white sputum for 1 month. Chest computed tomography showed multiple bilateral subpleural nodules and plaques accompanied by air bronchograms, which were most concentrated in the lower lobe of his right lung. Positron emission tomography indicated increased radioactivity uptake with a maximum standardized uptake value of 3.5. Positron emission tomography/computed tomography showed a soft tissue density lesion in his left adrenal gland with a maximum standardized uptake value of 4.1. The positron emission tomography/computed tomography appearance suggested a primary colloid adenocarcinoma in the lower lobe of his right lung accompanied by intrapulmonary and left adrenal gland metastases. The diagnostic rate of colloid adenocarcinoma can be increased by combining the anatomic and metabolic information of lesions. The advantage of positron emission tomography/computed tomography in the diagnosis of colloid adenocarcinoma, as with other cancers, is the ability to locate extrapulmonary disease, facilitating clinical staging.

  8. Positron emission tomography of malignant tumours at head and neck. Evaluation of the diagnostic value of positron emission tomography by comparison with computed tomography

    International Nuclear Information System (INIS)

    Kettler, Nele

    2011-01-01

    Imaging methods for early, accurate diagnosis and aftercare of malignant growths is currently one of the most important research topics. The objective of this thesis is to evaluate the diagnostic value of FDG-positron emission tomography by comparison with computed tomography for patients with squamous cell carcinoma, malignant melanoma or sarcoma at head and neck. Measurement criteria are sensitivity and specificity. A retrospective evaluation of 100 examinations on 85 patients of University clinic Aachen was performed. The examination reports were supported by reports from histology, positron emission tomography and computed tomography. In each case, the histological results were assumed to provide a reliable benchmark. Sensitivity and specificity for the primary tumour site, metastatic lymphatic nodes and defined anatomic structures were compared across all patients. Comparisons were also performed on sub groups separated by gender, cancer type and the time and frequency at which tumours arose. The statistic analysis was done with MedCalc. Results: The results for sensitivity and specificity of the primary tumour site were 86.42% and 42.86%, and 64.71% and 66.07%, for positron emission tomography and computed tomography respectively. The results for the lymphatic nodes were 51.52% and 92.86% and 64.71% and 66.07%. When the constituent anatomic structures were evaluated separately, the specificity was significantly higher. The separation by gender showed no difference. Because the classification by tumor type resulted in samples that were of varying size, a comparison was difficult. For the diagnosis of primary tumours, the examination with positron emission tomography was superior, whereas computed tomography proved more effective for the diagnosis of recurrent tumours. For the diagnosis of the main tumour site, both methods were shown to be equally suitable. For the assessment of lymphatic nodes, positron emission tomography was superior to computed tomography

  9. Fasciola Hepatica Mimicking Malignancy on 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

    Directory of Open Access Journals (Sweden)

    Erdem Sürücü

    2016-10-01

    Full Text Available A 48-year-old female with complaints of gastrointestinal symptoms such as abdominal pain, fatigue, vomiting, nausea, and weight loss was diagnosed with neuroendocrine tumor after removal of a 2 mm lesion from the stomach with endoscopic biopsy. Her magnetic resonance imaging that was performed due to on-going symptoms showed multiple linear hypointense lesions in the liver. Positron emission tomography/computed tomography (PET/CT scan was performed for differential diagnosis, which showed high fluorodeoxyglucose (FDG uptake in these lesions. Clinical and laboratory findings revealed the final diagnosis as Fasciola hepatica. The imaging features of this case is presented to aid in differentiating this infectious disease from malignancy and avoid misdiagnosis on FDG-PET/CT.

  10. Fasciola Hepatica Mimicking Malignancy on 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

    Science.gov (United States)

    Sürücü, Erdem; Demir, Yusuf; Dülger, Ahmet C.; Batur, Abdüssamed; Ölmez, Şehmus; Kitapçı, Mehmet T.

    2016-01-01

    A 48-year-old female with complaints of gastrointestinal symptoms such as abdominal pain, fatigue, vomiting, nausea, and weight loss was diagnosed with neuroendocrine tumor after removal of a 2 mm lesion from the stomach with endoscopic biopsy. Her magnetic resonance imaging that was performed due to on-going symptoms showed multiple linear hypointense lesions in the liver. Positron emission tomography/computed tomography (PET/CT) scan was performed for differential diagnosis, which showed high fluorodeoxyglucose (FDG) uptake in these lesions. Clinical and laboratory findings revealed the final diagnosis as Fasciola hepatica. The imaging features of this case is presented to aid in differentiating this infectious disease from malignancy and avoid misdiagnosis on FDG-PET/CT. PMID:27751978

  11. Brain perfusion single photon emission computed tomography in major psychiatric disorders: From basics to clinical practice

    International Nuclear Information System (INIS)

    Santra, Amburanjan; Kumar, Rakesh

    2014-01-01

    Brain single photon emission computed tomography (SPECT) is a well-established and reliable method to assess brain function through measurement of regional cerebral blood flow (rCBF). It can be used to define a patient's pathophysiological status when neurological or psychiatric symptoms cannot be explained by anatomical neuroimaging findings. Though there is ample evidence validating brain SPECT as a technique to track human behavior and correlating psychiatric disorders with dysfunction of specific brain regions, only few psychiatrists have adopted brain SPECT in routine clinical practice. It can be utilized to evaluate the involvement of brain regions in a particular patient, to individualize treatment on basis of SPECT findings, to monitor the treatment response and modify treatment, if necessary. In this article, we have reviewed the available studies in this regard from existing literature and tried to present the evidence for establishing the clinical role of brain SPECT in major psychiatric illnesses

  12. Two methods for calculating regional cerebral blood flow from emission computed tomography of inert gas concentrations

    DEFF Research Database (Denmark)

    Kanno, I; Lassen, N A

    1979-01-01

    Two methods are described for calculation of regional cerebral blood flow from completed tomographic data of radioactive inert gas distribution in a slice of brain tissue. It is assumed that the tomographic picture gives the average inert gas concentration in each pixel over data collection perio...... are implemented using synthetic data of xenon-133 emission computed tomography and some of the difficulties likely to be encountered in practice are stressed.......Two methods are described for calculation of regional cerebral blood flow from completed tomographic data of radioactive inert gas distribution in a slice of brain tissue. It is assumed that the tomographic picture gives the average inert gas concentration in each pixel over data collection periods...

  13. Complementary single photon emission computed tomography of the brain: Xe-133 and iodoamphetamine

    International Nuclear Information System (INIS)

    Simon, T.R.; Devous, M.; Raese, J.D.; Homan, R.; Bonte, F.F.

    1986-01-01

    Xe-133 and I-123 iodoamphetamin (IMP) emission computed tomography studies of 32 patients with neurologic (n = 7) or psychiatric (n = 25) diagnoses were used to determine whether the modalities yield complementary diagnostic information. The images, interpreted by two observers, differed in 15 (47%) cases. In schizophrenic patients, 11(61%) abnormalities were identified by Xe-133 imaging and 15(83%) by IMP. The abnormalities involved principally the frontal lobes and were identified in eight (73%) cases by Xe-133 imaging and in ten (67%) cases by IMP. In all four patients with arteriovenous malformations the imaging results were abnormal: Xe-133 showed increased flow while IMP revealed localized decreased activity in one patient. Imaging patterns for seizures, depression and psychoses also differed. Thus, Xe-133 and IMP appear complementary in their portrayal of brain function

  14. Voluminal modelling for the characterization of wastes packages by gamma emission computed tomography

    International Nuclear Information System (INIS)

    Pettier, J.L.; Thierry, R.

    2001-01-01

    The aim of this work is to model the measurement process used for multi-photon emission computed tomography on nuclear waste drum. Our model MEPHISTO (Multi-Energy PHoton Imagery through Segmented TOmography) takes into account all phenomena influencing gamma emergent flux and high resolution spectrometric measurements using an HpGe detector through a collimator aperture. These phenomena are absorption and Compton scattering of gamma photons in waste drum, geometrical blur, spatial and energetic response of the detector. The analysis of results shows better localisation and quantification performances compared with a Ray-Driven method. It proves the importance of an accurate modelization of collimated measurements to reduce noise and stabilize iterative image reconstructions. (authors)

  15. Brain perfusion single photon emission computed tomography in children after acute encephalopathy

    International Nuclear Information System (INIS)

    Kurihara, Mana; Nakae, Yoichiro; Kohagizawa, Toshitaka; Eto, Yoshikatsu

    2005-01-01

    We studied single photon emission computed tomography (SPECT) of 15 children with acute encephalopathy after more than 1 year from the onset, using technetium-99 m-L, L-ethyl cystinate dimer ( 99m Tc-ECD) and a three-dementional stereotaxic region of interest template. Regional cerebral blood flow was evaluated and divided in three groups according to the severity of disability: absent or mild, moderate, and severe. There was no abnormality on SPECT in the patients without disability or with mild disability. Diffuse hypoperfusion was shown in the groups with moderate and severe disability. The patients with severe disability showed hypoperfusion in the pericallosal, frontal and central areas which was more pronounced than in the patients with moderate disability. (author)

  16. Fasciola Hepatica Mimicking Malignancy on 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography.

    Science.gov (United States)

    Sürücü, Erdem; Demir, Yusuf; Dülger, Ahmet C; Batur, Abdüssamed; Ölmez, Şehmus; Kitapçı, Mehmet T

    2016-10-05

    A 48-year-old female with complaints of gastrointestinal symptoms such as abdominal pain, fatigue, vomiting, nausea, and weight loss was diagnosed with neuroendocrine tumor after removal of a 2 mm lesion from the stomach with endoscopic biopsy. Her magnetic resonance imaging that was performed due to on-going symptoms showed multiple linear hypointense lesions in the liver. Positron emission tomography/computed tomography (PET/CT) scan was performed for differential diagnosis, which showed high fluorodeoxyglucose (FDG) uptake in these lesions. Clinical and laboratory findings revealed the final diagnosis as Fasciola hepatica. The imaging features of this case is presented to aid in differentiating this infectious disease from malignancy and avoid misdiagnosis on FDG-PET/CT.

  17. Hot water epilepsy: Phenotype and single photon emission computed tomography observations

    Directory of Open Access Journals (Sweden)

    Mehul Patel

    2014-01-01

    Full Text Available We studied the anatomical correlates of reflex hot water epilepsy (HWE using multimodality investigations viz. magnetic resonance imaging (MRI, electroencephalography (EEG, and single photon emission computed tomography (SPECT. Five men (mean age: 27.0 ΁ 5.8 years with HWE were subjected to MRI of brain, video-EEG studies, and SPECT scan. These were correlated with phenotypic presentations. Seizures could be precipitated in three patients with pouring of hot water over the head and semiology of seizures was suggestive of temporal lobe epilepsy. Ictal SPECT showed hyperperfusion in: left medial temporal - one, left lateral temporal - one, and right parietal - one. Interictal SPECT was normal in all five patients and did not help in localization. MRI and interictal EEG was normal in all the patients. The clinical and SPECT studies suggested temporal lobe as the seizure onset zone in some of the patients with HWE.

  18. Prognostic Evaluation of 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Endometrial Cancer

    DEFF Research Database (Denmark)

    Vilstrup, Mie Holm; Jochumsen, Kirsten M; Hess, Søren

    2017-01-01

    OBJECTIVE: This study aims to ascertain if semiquantitative measurements derived from F-fluorodeoxyglucose positron emission tomography/computed tomography can be used as prognostic markers in patients with newly diagnosed endometrial cancer. MATERIALS AND METHODS: Patients with endometrial cancer...... proportional regression models were used for prognostic evaluation. RESULTS: Eighty-three patients (median age, 69.9 y; range, 26.8-91.1) with primarily high-risk endometrial cancer or suspected high The International Federation of Gynecology and Obstetrics stage were included. Mean follow-up time was 3......-risk endometrial cancer. Thus, SUVmax and cTLG might help identify patients who could benefit from a more aggressive treatment strategy or closer surveillance....

  19. Statistical evaluation of single-photon emission computed tomography image using smoothed bootstrap method

    International Nuclear Information System (INIS)

    Tsukamoto, Megumi; Hatabu, Asuka; Takahashi, Yoshitake; Matsuda, Hiroshi; Okamoto, Kousuke; Yamashita, Noriyuki; Takagi, Tatsuya

    2013-01-01

    Many of the neurodegenerative diseases associated with a decrease in regional cerebral blood flow (rCBF) are untreatable, and the appropriate therapeutic strategy is to slow the progression of the disease. Therefore, it is important that a definitive diagnosis is made as soon as possible when such diseases are suspected. Diagnostic imaging methods, such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT), play an important role in such a definitive diagnosis. Since several problems arise when evaluating these images visually, a procedure to evaluate them objectively is necessary, and studies of image analyses using statistical evaluations have been suggested. However, the assumed data distribution in a statistical procedure may occasionally be inappropriate. Therefore, to evaluate the decrease of rCBF, it is important to use a statistical procedure without assumptions about the data distribution. In this study, we propose a new procedure that uses nonparametric or smoothed bootstrap methods to calculate a standardized distribution of the Z-score without assumptions about the data distribution. To test whether the judgment of the proposed procedure is equivalent to that of an evaluation based on the Z-score with a fixed threshold, the procedure was applied to a sample data set whose size was large enough to be appropriate for the assumption of the Z-score. As a result, the evaluations of the proposed procedure were equivalent to that of an evaluation based on the Z-score. (author)

  20. Monitoring Damage Using Acoustic Emission Source Location and Computational Geometry in Reinforced Concrete Beams

    Directory of Open Access Journals (Sweden)

    Jason Maximino C. Ongpeng

    2018-01-01

    Full Text Available Non-destructive testing in reinforced concrete (RC for damage detection is still limited to date. In monitoring the damage in RC, 18 beam specimens with varying water cement ratios and reinforcements were casted and tested using a four-point bending test. Repeated step loads were designed and at each step load acoustic emission (AE signals were recorded and processed to obtain the acoustic emission source location (AESL. Computational geometry using a convex hull algorithm was used to determine the maximum volume formed by the AESL inside the concrete beam in relation to the load applied. The convex hull volume (CHV showed good relation to the damage encountered until 60% of the ultimate load at the midspan was reached, where compression in the concrete occurred. The changes in CHV from 20 to 40% and 20 to 60% load were five and 13 times from CHV of 20% load for all beams, respectively. This indicated that the analysis in three dimensions using CHV was sensitive to damage. In addition, a high water-cement ratio exhibited higher CHV formation compared to a lower water-cement ratio due to its ductility where the movement of AESL becomes wider.

  1. Cone beam tomography of the heart using single-photon emission-computed tomography

    International Nuclear Information System (INIS)

    Gullberg, G.T.; Christian, P.E.; Zeng, G.L.; Datz, F.L.; Morgan, H.T.

    1991-01-01

    The authors evaluated cone beam single-photon emission-computed tomography (SPECT) of the heart. A new cone beam reconstruction algorithm was used to reconstruct data collected from short scan acquisitions (of slightly more than 180 degrees) of a detector anteriorally traversing a noncircular orbit. The less than 360 degrees acquisition was used to minimize the attenuation artifacts that result from reconstructing posterior projections of 201T1 emissions from the heart. The algorithm includes a new method for reconstructing truncated projections of background tissue activity that eliminates reconstruction ring artifacts. Phantom and patient results are presented which compare a high-resolution cone beam collimator (50-cm focal length; 6.0-mm full width at half maximum [FWHM] at 10 cm) to a low-energy general purpose (LEGP) parallel hole collimator (8.2-mm FWHM at 10 cm) which is 1.33 times more sensitive. The cone beam tomographic results are free of reconstruction artifacts and show improved spatial and contrast resolution over that obtained with the LEGP parallel hole collimator. The limited angular sampling restrictions and truncation problems associated with cone beam tomography do not deter from obtaining diagnostic information. However, even though these preliminary results are encouraging, a thorough clinical study is still needed to investigate the specificity and sensitivity of cone beam tomography

  2. Utility of single photon emission computed tomography/computed tomography imaging in evaluation of chronic low back pain

    International Nuclear Information System (INIS)

    Harisankar, Chidambaram Natrajan Balasubramanian; Mittal, Bhagwant Rai; Bhattacharya, Anish; Singh, Paramjeet; Sen, Ramesh

    2012-01-01

    Abnormal morphologic findings in imaging were thought to explain the etiology of low back pain (LBP). However, it is now known that variety of morphologic abnormalities is noted even in asymptomatic individuals. Single photon emission computed tomography/computed tomography (SPECT/CT) could be used to differentiate incidental findings from clinically significant findings. This study was performed to define the SPECT/CT patterns in patients with LBP and to correlate these with clinical and magnetic resonance imaging (MRI) findings. Thirty adult patients with LBP of duration 3 months or more were prospectively evaluated in this study. Patients with known or suspected malignancy, trauma or infectious processes were excluded. A detailed history of sensory and motor symptoms and neurologic examination was performed. All the patients were subjected to MRI and bone scintigraphy with hybrid SPECT/CT of the lumbo-sacral spine within 1 month of each other. The patients were classified into those with and without neurologic symptoms, activity limitation. The findings of clinical examination and imaging were compared. MRI and SPECT/CT findings were also compared. Thirty patients (18 men and 12 women; mean age 38 years; range 17-64 years) were eligible for the study. Clinically, 14 of 30 (46%) had neurologic signs and or symptoms. Six of the 30 patients (20%) had positive straight leg raising test (SLRT). Twenty-two of the 30 patients (73%) had SPECT abnormality. Most frequent SPECT/CT abnormality was tracer uptake in the anterior part of vertebral body with osteophytes/sclerotic changes. Significant positive agreement was noted between this finding and MRI evidence of degenerative disc disease. Only 13% of patients had more than one abnormality in SPECT. All 30 patients had MRI abnormalities. The most frequent abnormality was degenerative disc disease and facet joint arthropathy. MRI showed single intervertebral disc abnormality in 36% of the patients and more than one

  3. Role of Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Diagnostic Evaluation of Carcinoma Urinary Bladder: Comparison with Computed Tomography

    International Nuclear Information System (INIS)

    Chakraborty, Dhritiman; Mittal, Bhagwant Rai; Kashyap, Raghava; Mete, Utham Kumar; Narang, Vikram; Das, Ashim; Bhattacharya, Anish; Khandelwal, Niranjan; Mandal, Arup K.

    2014-01-01

    Bladder carcinoma is the most frequent tumor of the urinary tract and accounts 7% of all malignancies in men and 2% of all malignancies in women. This retrospective study was carried out to assess the diagnostic utility of F18-fludeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the imaging evaluation of bladder carcinoma. Seventy-seven consecutive patients diagnosed to have carcinoma urinary bladder referred for F18-FDG PET/CT were included in this study. Thirty-four patients were for initial staging after transurethral biopsy and remaining 43 patients were for restaging. All patients also underwent CT scan of the abdomen and pelvis. PET/CT findings were correlated with diagnostic CT scan and histopathological findings. In 30 of the 34 patients for initial staging, both PET/CT and CT confirmed the primary lesion in the bladder. Histopathology report was available in 23 patients. Lymph nodes FDG uptake reported to be metastatic in 10/23 patients while CT detected lymph node metastasis in 12 patients. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy have been calculated to be 87.5%, 80%, 70%, 92%, 82% for PET/CT and 66%, 57%, 50%, 72%, 60% for CT respectively. PET/CT detected metastatic disease in 8 patients whereas CT detected in 4 patients. Of the 43 patients for restaging, local recurrence was detected in 24 patients on both PET/CT and CT. Histopathology report was available in 17 patients. Sensitivity, specificity, PPV, NPV and accuracy were 85%, 60%, 60%, 85%, 70% for PET/CT and 80%, 50%, 40%, 85%, 58% for CT respectively. Nineteen patients were detected to have metastatic disease by PET/CT, whereas CT detected metastases in 11 patients. F-18 FDG PET/CT is a very useful modality in pre-operative staging and monitoring after surgery, chemotherapy or radiotherapy of patients with carcinoma urinary bladder

  4. Is there any role of positron emission tomography computed tomography for predicting resectability of gallbladder cancer?

    Science.gov (United States)

    Kim, Jaihwan; Ryu, Ji Kon; Kim, Chulhan; Paeng, Jin Chul; Kim, Yong-Tae

    2014-05-01

    The role of integrated (18)F-2-fluoro-2-deoxy-D-glucose positron emission tomography computed tomography (PET-CT) is uncertain in gallbladder cancer. The aim of this study was to show the role of PET-CT in gallbladder cancer patients. Fifty-three patients with gallbladder cancer underwent preoperative computed tomography (CT) and PET-CT scans. Their medical records were retrospectively reviewed. Twenty-six patients underwent resection. Based on the final outcomes, PET-CT was in good agreement (0.61 to 0.80) with resectability whereas CT was in acceptable agreement (0.41 to 0.60) with resectability. When the diagnostic accuracy of the predictions for resectability was calculated with the ROC curve, the accuracy of PET-CT was higher than that of CT in patients who underwent surgical resection (P=0.03), however, there was no difference with all patients (P=0.12). CT and PET-CT had a discrepancy in assessing curative resection in nine patients. These consisted of two false negative and four false positive CT results (11.3%) and three false negative PET-CT results (5.1%). PET-CT was in good agreement with the final outcomes compared to CT. As a complementary role of PEC-CT to CT, PET-CT tended to show better prediction about resectability than CT, especially due to unexpected distant metastasis.

  5. Single photon emission computed tomography using a regularizing iterative method for attenuation correction

    International Nuclear Information System (INIS)

    Soussaline, Francoise; Cao, A.; Lecoq, G.

    1981-06-01

    An analytically exact solution to the attenuated tomographic operator is proposed. Such a technique called Regularizing Iterative Method (RIM) belongs to the iterative class of procedures where a priori knowledge can be introduced on the evaluation of the size and shape of the activity domain to be reconstructed, and on the exact attenuation distribution. The relaxation factor used is so named because it leads to fast convergence and provides noise filtering for a small number of iteractions. The effectiveness of such a method was tested in the Single Photon Emission Computed Tomography (SPECT) reconstruction problem, with the goal of precise correction for attenuation before quantitative study. Its implementation involves the use of a rotating scintillation camera based SPECT detector connected to a mini computer system. Mathematical simulations of cylindical uniformly attenuated phantoms indicate that in the range of a priori calculated relaxation factor a fast converging solution can always be found with a (contrast) accuracy of the order of 0.2 to 4% given that numerical errors and noise are or not, taken into account. The sensitivity of the (RIM) algorithm to errors in the size of the reconstructed object and in the value of the attenuation coefficient μ was studied, using the same simulation data. Extreme variations of +- 15% in these parameters will lead to errors of the order of +- 20% in the quantitative results. Physical phantoms representing a variety of geometrical situations were also studied

  6. Analytical computation of prompt gamma ray emission and detection for proton range verification

    Science.gov (United States)

    Sterpin, E.; Janssens, G.; Smeets, J.; Vander Stappen, François; Prieels, D.; Priegnitz, Marlen; Perali, Irene; Vynckier, S.

    2015-06-01

    A prompt gamma (PG) slit camera prototype recently demonstrated that Bragg Peak position in a clinical proton scanned beam could be measured with 1-2 mm accuracy by comparing an expected PG detection profile to a measured one. The computation of the expected PG detection profile in the context of a clinical framework is challenging but must be solved before clinical implementation. Obviously, Monte Carlo methods (MC) can simulate the expected PG profile but at prohibitively long calculation times. We implemented a much faster method that is based on analytical processing of precomputed MC data that would allow practical evaluation of this range monitoring approach in clinical conditions. Reference PG emission profiles were generated with MC simulations (PENH) in targets consisting of either 12C, 14N, 16O, 31P or 40Ca, with 10% of 1H. In a given geometry, the local PG emission can then be derived by adding the contribution of each element, according to the local energy of the proton obtained by continuous slowing down approximation and the local composition. The actual incident spot size is taken into account using an optical model fitted to measurements and by super sampling the spot with several rays (up to 113). PG transport in the patient/camera geometries and the detector response are modelled by convolving the PG production profile with a transfer function. The latter is interpolated from a database of transfer functions fitted to MC data (PENELOPE) generated for a photon source in a cylindrical phantom with various radiuses and a camera placed at various positions. As a benchmark, the analytical model was compared to MC and experiments in homogeneous and heterogeneous phantoms. Comparisons with MC were also performed in a thoracic CT. For all cases, the analytical model reproduced the prediction of the position of the Bragg peak computed with MC within 1 mm for the camera in nominal configuration. When compared to measurements, the shape of the profiles

  7. Analytical computation of prompt gamma ray emission and detection for proton range verification.

    Science.gov (United States)

    Sterpin, E; Janssens, G; Smeets, J; Vander Stappen, François; Prieels, D; Priegnitz, Marlen; Perali, Irene; Vynckier, S

    2015-06-21

    A prompt gamma (PG) slit camera prototype recently demonstrated that Bragg Peak position in a clinical proton scanned beam could be measured with 1-2 mm accuracy by comparing an expected PG detection profile to a measured one. The computation of the expected PG detection profile in the context of a clinical framework is challenging but must be solved before clinical implementation. Obviously, Monte Carlo methods (MC) can simulate the expected PG profile but at prohibitively long calculation times. We implemented a much faster method that is based on analytical processing of precomputed MC data that would allow practical evaluation of this range monitoring approach in clinical conditions. Reference PG emission profiles were generated with MC simulations (PENH) in targets consisting of either (12)C, (14)N, (16)O, (31)P or (40)Ca, with 10% of (1)H. In a given geometry, the local PG emission can then be derived by adding the contribution of each element, according to the local energy of the proton obtained by continuous slowing down approximation and the local composition. The actual incident spot size is taken into account using an optical model fitted to measurements and by super sampling the spot with several rays (up to 113). PG transport in the patient/camera geometries and the detector response are modelled by convolving the PG production profile with a transfer function. The latter is interpolated from a database of transfer functions fitted to MC data (PENELOPE) generated for a photon source in a cylindrical phantom with various radiuses and a camera placed at various positions. As a benchmark, the analytical model was compared to MC and experiments in homogeneous and heterogeneous phantoms. Comparisons with MC were also performed in a thoracic CT. For all cases, the analytical model reproduced the prediction of the position of the Bragg peak computed with MC within 1 mm for the camera in nominal configuration. When compared to measurements, the shape of the

  8. Analytical computation of prompt gamma ray emission and detection for proton range verification

    International Nuclear Information System (INIS)

    Sterpin, E; Vynckier, S; Janssens, G; Smeets, J; Stappen, François Vander; Prieels, D; Priegnitz, Marlen; Perali, Irene

    2015-01-01

    A prompt gamma (PG) slit camera prototype recently demonstrated that Bragg Peak position in a clinical proton scanned beam could be measured with 1–2 mm accuracy by comparing an expected PG detection profile to a measured one. The computation of the expected PG detection profile in the context of a clinical framework is challenging but must be solved before clinical implementation. Obviously, Monte Carlo methods (MC) can simulate the expected PG profile but at prohibitively long calculation times. We implemented a much faster method that is based on analytical processing of precomputed MC data that would allow practical evaluation of this range monitoring approach in clinical conditions.Reference PG emission profiles were generated with MC simulations (PENH) in targets consisting of either 12 C, 14 N, 16 O, 31 P or 40 Ca, with 10% of 1 H. In a given geometry, the local PG emission can then be derived by adding the contribution of each element, according to the local energy of the proton obtained by continuous slowing down approximation and the local composition. The actual incident spot size is taken into account using an optical model fitted to measurements and by super sampling the spot with several rays (up to 113). PG transport in the patient/camera geometries and the detector response are modelled by convolving the PG production profile with a transfer function. The latter is interpolated from a database of transfer functions fitted to MC data (PENELOPE) generated for a photon source in a cylindrical phantom with various radiuses and a camera placed at various positions.As a benchmark, the analytical model was compared to MC and experiments in homogeneous and heterogeneous phantoms. Comparisons with MC were also performed in a thoracic CT. For all cases, the analytical model reproduced the prediction of the position of the Bragg peak computed with MC within 1 mm for the camera in nominal configuration. When compared to measurements, the shape of the

  9. Single photon emission computed tomography scanning: A predictor of outcome in vegetative state of head injury

    Directory of Open Access Journals (Sweden)

    Pralaya Nayak

    2011-01-01

    Full Text Available Background: Neurotrauma is one of the most important causes of death and disability. Some of the severely head injured patients, failed to show significant improvement despite aggressive neurosurgical management and ended up in a vegetative state. Aims: To assess the outcome at six months and one year using Glasgow outcome scale (GOS, in this prospective study on patients with severe head injury, who remained vegetative at one month. Materials and Methods: This prospective study was carried out in the department of Neurosurgery, All India Institute of Medical Sciences (AIIMS, New Delhi, over a period of a year and a half (March 2002 through July 2003. Materials and Methods: In patients with severe head injury (GCS < 8, post resuscitation, neurological assessment was done with Glasgow coma scale (GCS, pupillary light reflex, doll′s eye movement and cold caloric test in all cases. Fifty patients, who remained vegetative post injury according to the criteria of Jennett and Plum, at one month, were considered for the study. Brain SPECT (Single Photon Emission Computed T omography Scanning was carried out in selected cases. Statistical analysis: Data analysis was done by Pearson′s chi-square test on computer software SPSS, Version 10 (California, USA. Results: Patients with preserved brainstem reflex and with no perfusion defect on SPECT scan had statistically significant favorable outcome. More than 40% of vegetative patients regained consciousness by the end of one year, of whom 24% had favorable outcome in the form of moderate disability and good recovery. Conclusion: SPECT is better than computed tomography/magnetic resonance imaging (CT/MRI as it assesses the cerebral perfusion and functional injury rather than detecting the lesions only. Further study with a control group is necessary to establish the role of SPECT in head injury.

  10. [Analysis of single-photon emission computed tomography in patients with hypertensive encephalopathy complicated with previous hypertensive crisis].

    Science.gov (United States)

    Kustkova, H S

    2012-01-01

    In cerebrovascular diseases pefuzionnaya single photon emission computed tomography with lipophilic amines used for the diagnosis of functional disorders of cerebral blood flow. Quantitative calculations helps clarify the nature of vascular disease and clarify the adequacy and effectiveness of the treatment. In this modern program for SPECT ensure conduct not only as to the calculation of blood flow, but also make it possible to compute also the absolute values of cerebral blood flow.

  11. The value of positron emission tomography/computed tomography for evaluating metastatic disease in patients with pancreatic cancer.

    Science.gov (United States)

    Kim, Mi-Jin; Lee, Kwang Hyuck; Lee, Kyu Taek; Lee, Jong Kyun; Ku, Bon-Ho; Oh, Cho-Rong; Heo, Jin Seok; Choi, Seong-Ho; Choi, Dong Wook

    2012-08-01

    Routine application of positron emission tomography/computed tomography (PET/CT) for pancreatic cancer staging remains a controversial approach. The purpose of this study was to reassess the clinical impact of PET/CT for the detection of distant metastasis of pancreatic cancer. From January 2006 to June 2009, 125 patients with histologically proven pancreatic cancer that had undergone PET/CT at our hospital were retrospectively reviewed. To evaluate the clinical efficacy of PET/CT on the management plan, the post-PET/CT management plans were compared with the pre-PET/CT management plans. After the conventional staging workup, we determined that 76 patients (60.8%) had resectable lesions, whereas 48 patients had unresectable lesions. One patient underwent explorative laparotomy due to equivocal resectability. Positron emission tomography/computed tomography diagnosed distant metastasis in only 2 (2.6%) of the 76 patients with resectable lesions, and these patients did not undergo unnecessary surgical treatment. Complete resection was not performed in 8 of the 74 operative patients because they had distant metastasis detected during the operative procedure. Positron emission tomography/computed tomography diagnosed distant metastasis in 32 of the 44 patients with metastatic lesions that were histologically shown to have sensitivity of 72.7%. Positron emission tomography/computed tomography has a limited role in the evaluation of metastatic disease from pancreatic cancer.

  12. Incidental head and neck findings on 18F-fluoro-deoxy-glucose positron emission tomography computed tomography.

    Science.gov (United States)

    Williams, S P; Kinshuck, A J; Williams, C; Dwivedi, R; Wieshmann, H; Jones, T M

    2015-09-01

    The overlapping risk factors for lung and head and neck cancer present a definite risk of synchronous malignant pathology. This is the first study to specifically review incidental positron emission tomography computed tomography findings in the head and neck region in lung carcinoma patients. A retrospective review was performed of all lung cancer patients who underwent positron emission tomography computed tomography imaging over a five-year period (January 2008 - December 2012), identified from the Liverpool thoracic multidisciplinary team database. Six hundred and nine patients underwent positron emission tomography computed tomography imaging over this period. In 76 (12.5 per cent) scans, incidental regions of avid 18F-fluoro-deoxy-glucose uptake were reported in the head and neck region. In the 28 patients who were fully investigated, there were 4 incidental findings of malignancy. In lung cancer patients undergoing investigative positron emission tomography computed tomography scanning, a significant number will also present with areas of clinically significant 18F-fluoro-deoxy-glucose uptake in the head and neck region. Of these, at least 5 per cent may have an undiagnosed malignancy.

  13. Few-view single photon emission computed tomography (SPECT) reconstruction based on a blurred piecewise constant object model

    DEFF Research Database (Denmark)

    Wolf, Paul A.; Jørgensen, Jakob Sauer; Schmidt, Taly G.

    2013-01-01

    A sparsity-exploiting algorithm intended for few-view Single Photon Emission Computed Tomography (SPECT) reconstruction is proposed and characterized. The algorithm models the object as piecewise constant subject to a blurring operation. To validate that the algorithm closely approximates the true...

  14. Diagnosing Alzheimer's disease in elderly, mildly demented patients: the impact of routine single photon emission computed tomography

    NARCIS (Netherlands)

    van Gool, W. A.; Walstra, G. J.; Teunisse, S.; van der Zant, F. M.; Weinstein, H. C.; van Royen, E. A.

    1995-01-01

    Based on the observation of bilateral temporoparietal hypoperfusion in Alzheimer's disease (AD), single photon emission computed tomography (SPECT) is advocated by some as a powerful diagnostic tool in the evaluation of demented patients. We studied whether routine brain SPECT in elderly, mildly

  15. Report of two cases of fluorodeoxyglucose positron emission tomography/computed tomography appearance of hibernoma: A rare benign tumor

    International Nuclear Information System (INIS)

    Agrawal, Archi; Kembhavi, Seema; Purandare, Nilendu; Shah, Sneha; Rangarajan, Venkatesh

    2014-01-01

    False-positive findings are commonly seen in positron emission tomography computed tomography imaging. One of the most common false positive finding is uptake of fluorodeoxyglucose in brown adipose tissue. Herein, we report two cases with incidentally detected hibernomas-a brown fat containing tumor with metabolic activity

  16. Unusual sites of metastatic recurrence of osteosarcoma detected on fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography

    International Nuclear Information System (INIS)

    Kabnurkar, Rasika; Agrawal, Archi; Rekhi, Bharat; Purandare, Nilendu; Shah, Sneha; Rangarajan, Venkatesh

    2015-01-01

    Osteosarcoma (OS) is the most common nonhematolymphoid primary bone malignancy characterized by osteoid or new bone formation. Lungs and bones are the most common sites of metastases. We report a case where unusual sites of the soft tissue recurrence from OS were detected on restaging fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography scan done post 6 years of disease free interval

  17. Exercise echocardiography and single photon emission computed tomography in patients with left anterior descending coronary artery stenosis

    NARCIS (Netherlands)

    A. Salustri (Alessandro); M. Pozzoli (M.); B. Ilmer; W.R.M. Hermans (Walter); A.E.M. Reijs (Ambroos); J.H.C. Reiber (Johan); J.R.T.C. Roelandt (Jos); P.M. Fioretti (Paolo)

    1992-01-01

    textabstractTo compare the diagnostic value of exercise echocardiography and perfusion single photon emission computed tomography (SPECT) in the detection of the presence and the severity of coronary artery disease, we studied 21 patients with isolated stenosis of different degree of the left

  18. Detection of non-aggressive stage IA lung cancer using chest computed tomography and positron emission tomography/computed tomography.

    Science.gov (United States)

    Shiono, Satoshi; Yanagawa, Naoki; Abiko, Masami; Sato, Toru

    2014-10-01

    In contrast to lung cancer with ground-glass opacity, the radiological investigation of solid lung cancer has not been well examined. The aim of this study was to explore chest computed tomography (CT) and positron emission tomography (PET)/CT findings with regard to outcomes after lung cancer surgery in order to radiologically classify clinical stage IA lung cancers by tumour aggressiveness. Three hundred and fifteen clinical stage IA patients were analysed. Four groups were defined by tumour solidity on CT and by the standardized uptake value (SUV) index on PET-CT (tumour maximum SUV/mean right liver lobe SUV). We analysed the association between radiological findings and both pathological invasiveness and postoperative outcome. Group A (n = 84) had an SUV index <1.0 and non-solid tumours, Group B (n = 24) had an SUV index <1.0 and solid tumours, Group C (n = 54) had an SUV index ≥1.0 and non-solid tumours, while Group D (n = 153) had an SUV index ≥1.0 and solid tumours. Invasive lung cancer was found in 2/84 (2.4%) patients in Group A, 1/24 (4.2%) in Group B, 13/54 (24.1%) in Group C and 58/153 (37.9%) in Group D (P < 0.01). The 5-year recurrence-free rate was 100% in Groups A and B, 90.3% in C and 65.7% in D (P < 0.01). The cancer-specific survival rate was 100% in A and B, 94.6% in C and 81.7% in D (P < 0.01). The present results suggest that preoperative PET/CT and thin-section CT findings provide important information for a selection of surgical procedures for clinical stage IA lung cancers. In clinical stage IA lung cancers displaying solid or non-solid density in thin-section findings, an SUV index <1.0 may be a better criterion for detecting non-aggressive lung cancer even in solid lung cancers. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  19. The Comparison of Computed Tomography Perfusion, Contrast-Enhanced Computed Tomography and Positron-Emission Tomography/Computed Tomography for the Detection of Primary Esophageal Carcinoma.

    Science.gov (United States)

    Genc, Berhan; Kantarci, Mecit; Sade, Recep; Orsal, Ebru; Ogul, Hayri; Okur, Aylin; Aydin, Yener; Karaca, Leyla; Eroğlu, Atilla

    2016-01-01

    The purpose of this study was to investigate the efficiency of computed tomography perfusion (CTP), contrast-enhanced computed tomography (CECT) and 18F-fluoro-2-deoxy-D-glucose (18F-FDG) positron-emission tomography (PET/CT) in the diagnosis of esophageal cancer. This prospective study consisted of 33 patients with pathologically confirmed esophageal cancer, 2 of whom had an esophageal abscess. All the patients underwent CTP, CECT and PET/CT imaging and the imaging findings were evaluated. Sensitivity, specificity and positive and negative predictive values were calculated for each of the 3 imaging modalities relative to the histological diagnosis. Thirty-three tumors were visualized on CTP, 29 on CECT and 27 on PET/CT. Six tumors were stage 1, and 2 and 4 of these tumors were missed on CECT and PET/CT, respectively. Significant differences between CTP and CECT (p = 0.02), and between CTP and PET/CT (p = 0.04) were found for stage 1 tumors. Values for the sensitivity, specificity and positive and negative predictive values on CTP were 100, 100, 100 and 100%, respectively. Corresponding values on CECT were 93.94, 0, 93.94 and 0%, respectively, and those on PET/CT were 87.88, 0, 93.55 and 0%, respectively. Hence, the sensitivity, specificity and positive and negative predictive values of CTP were better than those of CECT and PET/CT. CTP had an advantage over CECT and PET/CT in detecting small lesions. CTP was valuable, especially in detecting stage 1 tumors. © 2016 S. Karger AG, Basel.

  20. Myocardial ischemia detection by artificial intelligence interpretation of Tl-201 tomograms

    International Nuclear Information System (INIS)

    Herbst, M.D.; Garcia, E.V.; Cooke, C.D.; Folks, R.D.; Ezquerra, N.F.

    1989-01-01

    This paper reports on an expert system environment which automatically assigned certainty factors to abnormal regions in stress and delayed myocardial thallium-201 polar bulls-eye plots. MYCIN-type algorithms propagated certainty factors for the presence, location, and character of each coronary lesion. Ninety-four previously validated rules that considered only stress perfusion defects spawned 91 new rules considering tracer redistribution. Fifteen new rules assessed vascular territories for the presence and location of fixed or reversible defects. This artificial intelligence tool can provide novice readers of cardiac T1-201 studies automatic, consistent, objective, and justified interpretations that consider artifacts, coronary territory overlap, and multiple defects

  1. The role of Tl-201 total body scintigraphy in follow up of thyroid carcinoma

    International Nuclear Information System (INIS)

    Hoefnagel, C.A.; Delprat, C.C.; Marcuse, H.R.

    1985-01-01

    To evaluate the reliability of the procedure T1-201 total body scintigraphy was performed in 294 patients (449 studies) after total thyroidectomy for thyroid carcinoma. Results were correlated with I-131-scintigraphy and tumor-marker levels (Tgb or Calcitonin/CEA). T1-201 total body scintigraphy was negative in 196 patients with no evidence of disease. T1-201-scintigraphy correctly detected tumor localizations in 24 of 30 patients with I-131-positive metastases. In 28 patients T2-201 total body scintigraphy revealed metastases which did not concentrate I-131. Histology/cytology confirmed thyroid carcinoma metastases in 16 patients and other pathology in 5 cases. 9 of 18 patients with medullary thyroid carcinoma (I-131-negative) had elevated Calcitonin/CEA-levels. The T1-201 scintigram was positive in 8 of these patients. Comparison of T1-201, I-131 and tumor markers showed that only combined use of these parameters provide complete reliability. The authors conclude that T1-201 total body scintigraphy is useful in follow up of thyroid carcinoma, especially when a discrepancy of the other parameters exists and particularly in medullary carcinoma. In long term follow up of patients who are unsuspected of disease after successful therapy for thyroid carcinoma one can rely on T1-201 total body scintigraphy in combination with tumor marker assays

  2. Coronary reserve of the right ventricle evaluated by double dose Tl-201 scintigraphy

    International Nuclear Information System (INIS)

    Sugihara, Hiroki; Adachi, Haruhiko; Nakagawa, Hiroaki

    1985-01-01

    Thallium-201 double dose scintigraphy was applied to exercise to estimate the coronary blood flow reserve of the left and right ventricles and this was compared with the degree of coronary artery stenosis. As an index of coronary reserve we measured the rate of change of blood flow distribution (ΔF) calculated from the change in myocardial radioactivity following thallium-201 injections, once at rest and once during exercise. With submaximal exercise the increases in ΔF of the left ventricle were less in patients with ischemic heart disease than in the control subjects, and were less as the number of diseased coronary vessels increased. The increases of ΔF of the right ventricle were less in patients with stenosis of the proximal portion of the right coronary artery than in patients without stenosis and in the control subjects. The more severe the stenosis of the proximal portion of the right coronary artery, the smaller the ΔF of the right ventricle. These results indicate that evaluation of the ΔF in the left and right ventricles is useful in estimating coronary artery stenosis. (author)

  3. Development of a simple photon emission computed tomography dedicated to the small animal

    International Nuclear Information System (INIS)

    Bekaert, V.

    2006-11-01

    The development of in vivo small animal imaging becomes essential to study human pathologies. The ImaBio project of Institut Pluridisciplinaire Hubert Curien (IPHC) fits in the process of developing new instruments for biomedical applications with the development of a multimodality imaging platform dedicated to small animal imaging (AMISSA). This thesis presents the study, the design and the development of a Single Photon Emission Computed Tomography (SPECT) which will be integrated to the AMISSA platform. The result of these developments is the possibility to obtain the spatial distribution of an injected molecule into the animal. The SPECT technical solutions are based on the acquired knowledge of the institute allowing the conception of a device with cameras adapted to the gamma detection produced by the radiotracers used in single photon imaging. In order to cover the entire of the transverse field of view, four gamma cameras are arranged in a ring around the volume of interest. Each camera consists of 5 individual modules based on a YAP:Ce crystal array, a multi-anode photomultiplier and a dedicated multichannel electronic device. Finally, 20 detection modules were calibrated to give the same result for an identical energy deposit. The data are acquired then process to extract the positions and the energies deposited by gamma photons in the crystals. This last information is then gathered to build the projections. The 3D reconstructed image from the projections is carried out by the sequence of two algorithms, analytical and iterative OS-EM, both modified to take into account the singular geometry of our detection system. Finally, the obtained image is fused with the anatomical information given by the micro Computed Tomography system. (author)

  4. Safety of ventilation/perfusion single photon emission computed tomography for pulmonary embolism diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Le Roux, Pierre-Yves; Palard, Xavier; Robin, Philippe; Abgral, Ronan; Querellou, Solene; Salaun, Pierre-Yves [Universite Europeenne de Bretagne, Brest (France); Universite de Brest, Brest (France); CHRU de la Cavale Blanche, Service de medecine nucleaire, Brest (France); Delluc, Aurelien; Couturaud, Francis [Universite Europeenne de Bretagne, Brest (France); Universite de Brest, Brest (France); CHRU de la Cavale Blanche, Departement de medecine interne et de pneumologie, Brest (France); Le Gal, Gregoire [Universite Europeenne de Bretagne, Brest (France); University of Ottawa, Ottawa Hospital Research Institute, Ottawa (Canada); CHRU de la Cavale Blanche, Departement de medecine interne et de pneumologie, Brest (France); Universite de Brest, Brest (France)

    2014-10-15

    The aim of this management outcome study was to assess the safety of ventilation/perfusion single photon emission computed tomography (V/Q SPECT) for the diagnosis of pulmonary embolism (PE) using for interpretation the criteria proposed in the European Association of Nuclear Medicine (EANM) guidelines for V/Q scintigraphy. A total of 393 patients with clinically suspected PE referred to the Nuclear Medicine Department of Brest University Hospital from April 2011 to March 2013, with either a high clinical probability or a low or intermediate clinical probability but positive D-dimer, were retrospectively analysed. V/Q SPECT were interpreted by the attending nuclear medicine physician using a diagnostic cut-off of one segmental or two subsegmental mismatches. The final diagnostic conclusion was established by the physician responsible for patient care, based on clinical symptoms, laboratory test, V/Q SPECT and other imaging procedures performed. Patients in whom PE was deemed absent were not treated with anticoagulants and were followed up for 3 months. Of the 393 patients, the prevalence of PE was 28 %. V/Q SPECT was positive for PE in 110 patients (28 %) and negative in 283 patients (72 %). Of the 110 patients with a positive V/Q SPECT, 78 (71 %) had at least one additional imaging test (computed tomography pulmonary angiography or ultrasound) and the diagnosis of PE was eventually excluded in one patient. Of the 283 patients with a negative V/Q SPECT, 74 (26 %) patients had another test. The diagnosis of PE was finally retained in one patient and excluded in 282 patients. The 3-month thromboembolic risk in the patients not treated with anticoagulants was 1/262: 0.38 % (95 % confidence interval 0.07-2.13). A diagnostic management including V/Q SPECT interpreted with a diagnostic cut-off of ''one segmental or two subsegmental mismatches'' appears safe to exclude PE. (orig.)

  5. IMPROVING EMISSIONS ESTIMATES WITH COMPUTATIONAL INTELLIGENCE, DATABASE EXPANSION, AND COMPREHENSIVE VALIDATION

    Science.gov (United States)

    The report discusses an EPA investigation of techniques to improve methods for estimating volatile organic compound (VOC) emissions from area sources. Using the automobile refinishing industry for a detailed area source case study, an emission estimation method is being developed...

  6. Role of single photon emission computed tomography/computed tomography in diagnostic iodine-131 scintigraphy before initial radioiodine ablation in differentiated thyroid cancer

    International Nuclear Information System (INIS)

    Agrawal, Kanhaiyalal; Bhattacharya, Anish; Mittal, Bhagwant Rai

    2005-01-01

    The study was performed to evaluate the incremental value of single photon emission computed tomography/computed tomography (SPECT/CT) over planar radioiodine imaging before radioiodine ablation in the staging, management and stratification of risk of recurrence (ROR) in differentiated thyroid cancer (DTC) patients. Totally, 83 patients (21 male, 62 female) aged 17–75 (mean 39.9) years with DTC were included consecutively in this prospective study. They underwent postthyroidectomy planar and SPECT/CT scans after oral administration of 37–114 MBq iodine-131 (I-131). The scans were interpreted as positive, negative or suspicious for tracer uptake in the thyroid bed, cervical lymph nodes and sites outside the neck. In each case, the findings on planar images were recorded first, without knowledge of SPECT/CT findings. Operative and pathological findings were used for postsurgical tumor–node–metastasis staging. The tumor staging was reassessed after each of these two scans. Single photon emission computed tomography/computed tomography localized radioiodine uptake in the thyroid bed in 9/83 (10.8%) patients, neck nodes in 24/83 (28.9%) patients and distant metastases in 8/83 (9.6%) patients in addition to the planar study. Staging was changed in 8/83 (9.6%), ROR in 11/83 (13.2%) and management in 26/83 (31.3%) patients by the pretherapy SPECT/CT in comparison to planar imaging. SPECT/CT had incremental value in 32/83 patients (38.5%) over the planar scan. Single photon emission computed tomography/computed tomography is feasible during a diagnostic I-131 scan with a low amount of radiotracer. It improved the interpretation of pretherapy I-131 scintigraphy and changed the staging and subsequent patient management

  7. Single photon emission computed tomography in the diagnosis of Alzheimer's disease

    International Nuclear Information System (INIS)

    Hanyu, Haruo; Asano, Tetsuichi; Abe, Shin'e; Arai, Hisayuki; Iwamoto, Toshihiko; Takasaki, Masaru; Shindo, Hiroaki; Abe, Kimihiko

    1997-01-01

    Studies with single photon emission computed tomography (SPECT) have shown temporoparietal (TP) hypoperfusion in patients with Alzheimer's disease (AD). We evaluated the utility of this findings in the diagnosis of AD. SPECT images with 123 I-iodoamphetamine were analyzed qualitatively by a rater without knowledge of the subject's clinical status. Sixty-seven of 302 consecutive patients were judged as having TP hypoperfusion by SPECT imaging. This perfusion pattern was observed in 44 of 51 patients with AD, in 5 with mixed dementia, 8 with cerebrovascular disease (including 5 with dementia), 4 with Parkinson's disease (including 2 with dementia), 1 with normal pressure hydrocephalus, 1 with slowly progressive aphasia, 1 with progressive autonomic failure, 2 with age-associated memory impairment, and 1 with unclassified dementia. The sensitivity for AD was 86.3% (44 of 51 AD), and the specificity was 91.2% (229 of 251 non-AD). Next, we looked for differences in perfusion images between patients with AD and without AD. Some patients without AD had additional hypoperfusion beyond TP areas: deep gray matter hypoperfusion and diffuse frontal hypoperfusion, which could be used to differentiate them from the patients with AD. Others could not be distinguished from patients with AD by their perfusion pattern. Although patients with other cerebral disorders occasionally have TP hypoperfusion, this finding makes the diagnosis of AD very likely. (author)

  8. Single photon emission computed tomography in the diagnosis of Alzheimer`s disease

    Energy Technology Data Exchange (ETDEWEB)

    Hanyu, Haruo; Asano, Tetsuichi; Abe, Shin`e; Arai, Hisayuki; Iwamoto, Toshihiko; Takasaki, Masaru; Shindo, Hiroaki; Abe, Kimihiko [Tokyo Medical Coll. (Japan)

    1997-06-01

    Studies with single photon emission computed tomography (SPECT) have shown temporoparietal (TP) hypoperfusion in patients with Alzheimer`s disease (AD). We evaluated the utility of this findings in the diagnosis of AD. SPECT images with {sup 123}I-iodoamphetamine were analyzed qualitatively by a rater without knowledge of the subject`s clinical status. Sixty-seven of 302 consecutive patients were judged as having TP hypoperfusion by SPECT imaging. This perfusion pattern was observed in 44 of 51 patients with AD, in 5 with mixed dementia, 8 with cerebrovascular disease (including 5 with dementia), 4 with Parkinson`s disease (including 2 with dementia), 1 with normal pressure hydrocephalus, 1 with slowly progressive aphasia, 1 with progressive autonomic failure, 2 with age-associated memory impairment, and 1 with unclassified dementia. The sensitivity for AD was 86.3% (44 of 51 AD), and the specificity was 91.2% (229 of 251 non-AD). Next, we looked for differences in perfusion images between patients with AD and without AD. Some patients without AD had additional hypoperfusion beyond TP areas: deep gray matter hypoperfusion and diffuse frontal hypoperfusion, which could be used to differentiate them from the patients with AD. Others could not be distinguished from patients with AD by their perfusion pattern. Although patients with other cerebral disorders occasionally have TP hypoperfusion, this finding makes the diagnosis of AD very likely. (author)

  9. Gated single photon emission computer tomography for the detection of silent myocardial ischemia

    International Nuclear Information System (INIS)

    Pena Q, Yamile; Coca P, Marco Antonio; Batista C, Juan Felipe; Fernandez-Britto, Jose; Quesada P, Rodobaldo; Pena C; Andria

    2009-01-01

    Background: Asymptomatic patients with severe coronary atherosclerosis may have a normal resting electrocardiogram and stress test. Aim: To assess the yield of Gated Single Photon Emission Computer Tomography (SPECT) for the screening of silent myocardial ischemia in type 2 diabetic patients. Material and methods: Electrocardiogram, stress test and gated-SPECT were performed on 102 type 2 diabetic patients aged 60 ± 8 years without cardiovascular symptoms. All subjects were also subjected to a coronary angiography, whose results were used as gold standard. Results: Gated-SPECT showed myocardial ischemia on 26.5% of studied patients. The sensibility, specificity, accuracy, positive predictive value and negative predictive value were 92.3%, 96%, 95%, 88.8%, 97.3%, respectively. In four and six patients ischemia was detected on resting electrocardiogram and stress test, respectively. Eighty percent of patients with doubtful resting electrocardiogram results and 70% with a doubtful stress test had a silent myocardial ischemia detected by gated-SPECT. There was a good agreement between the results of gated-SPECT and coronary angiography (k =0.873). Conclusions: Gated-SPECT was an useful tool for the screening of silent myocardial ischemia

  10. Detecting Metastatic Bladder Cancer Using (18)F-Fluorodeoxyglucose Positron-Emission Tomography/Computed Tomography.

    Science.gov (United States)

    Öztürk, Hakan

    2015-10-01

    The purpose of this study was to retrospectively investigate the contribution of (18)F-fluorodeoxyglucose-positron emission tomography/computed tomography ((18)F-FDG-PET/CT) to detection of metastatic bladder cancer. The present study included 79 patients (69 men and 10 women) undergoing (18)F-FDG-PET/CT upon suspicion of metastatic bladder cancer between July 2007 and April 2013. The mean age was 66.1 years with a standard deviation of 10.7 years (range, 21 to 85 years). Patients were required to fast for 6 hours prior to scanning, and whole-body PET scanning from the skull base to the upper thighs was performed approximately 1 hour after intravenous injection of 555 MBq of (18)F-FDG. Whole body CT scanning was performed in the cranio-caudal direction. FDG-PET images were reconstructed using CT data for attenuation correction. Suspicious recurrent or metastatic lesions were confirmed by histopathology or clinical follow-up. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of (18)F-FDG-PET/CT were 89%, 78%, 90%, 75%, and 86%, respectively. (18)F-FDG-PET/CT can detect metastases with high sensitivity and positive predictive values in patients with metastatic bladder carcinoma.

  11. Single-photon emission computed tomographic findings and motor neuron signs in amyotrophic lateral sclerosis

    International Nuclear Information System (INIS)

    Terao, Shin-ichi; Sobue, Gen; Higashi, Naoki; Takahashi, Masahiko; Suga, Hidemichi; Mitsuma, Terunori

    1995-01-01

    123 I-amphetamine-single photon emission computed tomography (SPECT) was performed on 16 patients with amyotrophic lateral sclerosis (ALS) to investigate the correlation between regional cerebral blood flow (rCBF) and upper motor neuron signs. Significant decreased blood flow less than 2 SDs below the mean of controls was observed in the frontal lobe in 4 patients (25%) and in the frontoparietal lobe including the cortical motor area in 4 patients, respectively. The severity of extermity muscular weakness was significantly correlate with decrease in blood flow through the frontal lobe (p<0.05) and through the frontoparietal lobe (p<0.001). A significant correlation was also noted to exist between the severity of bulbar paralysis and decrease in blood flow through the frontoparietal lobe. No correlation, however, was observed between rCBF and severity of spasticity, presence or absence of Babinski's sign and the duration of illness. Although muscular weakness in the limbs and bulbar paralysis are not pure upper motor neuron signs, the observed reduction in blood flow through the frontal or frontoparietal lobes appears to reflect extensive progression of functional or organic lesions of cortical neurons including the motor area. (author)

  12. Musicogenic epilepsy: review of the literature and case report with ictal single photon emission computed tomography.

    Science.gov (United States)

    Wieser, H G; Hungerbühler, H; Siegel, A M; Buck, A

    1997-02-01

    We report a case of musicogenic epilepsy with ictal single photon emission computed tomography (SPECT) study and discuss the findings of this patient in the context of 76 cases with musicogenic epilepsy described in the literature and seven other cases followed in Zurich. We analyzed the 83 patients according to the precipitating musical factors, type of epilepsy, presumed localization of seizure onset, and demographic data. Fourteen of 83 patients (17%) had seizures triggered exclusively by music. At time of examination, music was the only known precipitating stimulus in 65 of 83 patients (78%). Various characteristics of the musical stimulus were significant, e.g., musical category, familiarity, and instruments. Musicogenic epilepsy is a particular form of epilepsy with a strong correlation to the temporal lobe and a right-sided preponderance. A high musial standard might predispose for musicogenic epilepsy. Moreover, the majority of cases do not fall into the category of a strictly defined "reflex epilepsy," but appear to depend on the indermediary of a certain emotional reaction mediated through limbic mesial temporal lobe structures.

  13. Comparison of Ga-67 planar imaging and single photon emission computed tomography in malignant chest disease

    International Nuclear Information System (INIS)

    Tumeh, S.S.; Rosenthal, D.; Kaplan, W.D.; English, R.E.; Holman, B.L.

    1985-01-01

    To determine the value of Ga-67 single photon emission computed tomography (SPECT) in patients (pts) with malignant chest disease, the authors compared Ga-67 planar scans (ps) and SPECT with the medical records in twenty-five consecutive patients. Twenty-three examinations were performed on 17 pts with Hodgkin's disease (HD) and three pts with non-Hodgkin's lymphoma. Five examinations were performed on 5 pts with bronchogenic carcinoma (BC). The two modalities were evaluated for (1) presence or absence of disease, (2) number of foci of abnormal uptake and (3) extent of disease. In pts with lymphoma, SPECT defined the extent of disease better than planar imaging in eight examinations; it demonstrated para-cardial involvement in one pt, separated hilar from mediastinal disease in 4, and demonstrated posterior mediastinal disease in 3. SPECT clarified suspicious foci on planar images in seven examinations, correctly ruled out disease in two pts with equivocal planar images and did not exchange planar image findings in six examinations. In pts with bronchogenic carcinoma, both medalities correctly ruled out mediastinal involvement in three pts. SPECT detected mediastinal lymph node involvement in one pt with equivocal planar images. Both SPECT and planar imaging missed direct tumor extension to the mediastinum in one pt. They conclude that Ga-67 with SPECT is better than planar images for staging of chest lymphoma and BC. Since it defines different lymph node groups it carries a good potential for staging as well as follow up of those pts

  14. Small-Animal Imaging Using Clinical Positron Emission Tomography/Computed Tomography and Super-Resolution

    Directory of Open Access Journals (Sweden)

    Frank P. DiFilippo

    2012-05-01

    Full Text Available Considering the high cost of dedicated small-animal positron emission tomography/computed tomography (PET/CT, an acceptable alternative in many situations might be clinical PET/CT. However, spatial resolution and image quality are of concern. The utility of clinical PET/CT for small-animal research and image quality improvements from super-resolution (spatial subsampling were investigated. National Electrical Manufacturers Association (NEMA NU 4 phantom and mouse data were acquired with a clinical PET/CT scanner, as both conventional static and stepped scans. Static scans were reconstructed with and without point spread function (PSF modeling. Stepped images were postprocessed with iterative deconvolution to produce super-resolution images. Image quality was markedly improved using the super-resolution technique, avoiding certain artifacts produced by PSF modeling. The 2 mm rod of the NU 4 phantom was visualized with high contrast, and the major structures of the mouse were well resolved. Although not a perfect substitute for a state-of-the-art small-animal PET/CT scanner, a clinical PET/CT scanner with super-resolution produces acceptable small-animal image quality for many preclinical research studies.

  15. Single photon emission computed tomography (SPECT) in seizure disorders in childhood

    International Nuclear Information System (INIS)

    Vles, J.S.H.; Demandt, E.; Ceulemans, B.; de Roo, M.; Casaer, P.J.M.

    1990-01-01

    In 38 children with partial seizures, the EEG, CT and NMR findings were compared to the results obtained with Tc99m HMPAO single photon emission computed tomography (SPECT) in order to determine whether SPECT is a useful adjunct to EEG, CT and NMR in this age group. In 3 out of 7 patients with a normal EEG, SPECT showed focal abnormalities. Nine patients whose EEGs did not show adequate lateralization had an abnormal SPECT which revealed a focus. In 14 out of 21 patients with a normal CT, SPECT showed focal changes in 13 patients and diffuse changes in the other one. In 7 out of 12 patients with a normal NMR, SPECT showed focal abnormalities. Although clinical history and a careful description of the seizures are the most valuable information in partial seizure disorders, SPECT imaging gives valuable additional information, which might target treatment. SPECT was superior to CT and NMR with respect to the depiction of some kind of abnormality. (author)

  16. Restoration filtering based on projection power spectrum for single-photon emission computed tomography

    International Nuclear Information System (INIS)

    Kubo, Naoki

    1995-01-01

    To improve the quality of single-photon emission computed tomographic (SPECT) images, a restoration filter has been developed. This filter was designed according to practical 'least squares filter' theory. It is necessary to know the object power spectrum and the noise power spectrum. The power spectrum is estimated from the power spectrum of a projection, when the high-frequency power spectrum of a projection is adequately approximated as a polynomial exponential expression. A study of the restoration with the filter based on a projection power spectrum was conducted, and compared with that of the 'Butterworth' filtering method (cut-off frequency of 0.15 cycles/pixel), and 'Wiener' filtering (signal-to-noise power spectrum ratio was a constant). Normalized mean-squared errors (NMSE) of the phantom, two line sources located in a 99m Tc filled cylinder, were used. NMSE of the 'Butterworth' filter, 'Wiener' filter, and filtering based on a power spectrum were 0.77, 0.83, and 0.76 respectively. Clinically, brain SPECT images utilizing this new restoration filter improved the contrast. Thus, this filter may be useful in diagnosis of SPECT images. (author)

  17. Astigmatic single photon emission computed tomography imaging with a displaced center of rotation

    International Nuclear Information System (INIS)

    Wang, H.; Smith, M.F.; Stone, C.D.; Jaszczak, R.J.

    1998-01-01

    A filtered backprojection algorithm is developed for single photon emission computed tomography (SPECT) imaging with an astigmatic collimator having a displaced center of rotation. The astigmatic collimator has two perpendicular focal lines, one that is parallel to the axis of rotation of the gamma camera and one that is perpendicular to this axis. Using SPECT simulations of projection data from a hot rod phantom and point source arrays, it is found that a lack of incorporation of the mechanical shift in the reconstruction algorithm causes errors and artifacts in reconstructed SPECT images. The collimator and acquisition parameters in the astigmatic reconstruction formula, which include focal lengths, radius of rotation, and mechanical shifts, are often partly unknown and can be determined using the projections of a point source at various projection angles. The accurate determination of these parameters by a least squares fitting technique using projection data from numerically simulated SPECT acquisitions is studied. These studies show that the accuracy of parameter determination is improved as the distance between the point source and the axis of rotation of the gamma camera is increased. The focal length to the focal line perpendicular to the axis of rotation is determined more accurately than the focal length to the focal line parallel to this axis. copyright 1998 American Association of Physicists in Medicine

  18. Quantitation of postexercise lung thallium-201 uptake during single photon emission computed tomography

    International Nuclear Information System (INIS)

    Kahn, J.K.; Carry, M.M.; McGhie, I.; Pippin, J.J.; Akers, M.S.; Corbett, J.R.

    1989-01-01

    To test the hypothesis that analysis of lung thallium uptake measured during single photon emission computed tomography (SPECT) yields supplementary clinical information as reported for planar imaging, quantitative analysis of lung thallium uptake following maximal exercise was performed in 40 clinically normal subjects (Group 1) and 15 angiographically normal subjects (Group 2). Lung thallium uptake was measured from anterior projection images using a ratio of heart-to-lung activities. Seventy subjects with coronary artery disease (CAD) (Group 3) determined by angiography (greater than or equal to 70% luminal stenosis) underwent thallium perfusion SPECT. Thirty-nine percent of these subjects had multivessel and 61% had single vessel CAD. Lung thallium uptake was elevated in 47 of 70 (67%) Group 3 subjects. Group 3 subjects with elevated lung thallium uptake did not differ from Group 3 subjects with normal lung thallium uptake with respect to extent or distribution of coronary artery disease, left ventricular function, or severity of myocardial ischemia as determined by exercise and redistribution thallium SPECT. Thus, the measurement of thallium lung uptake from anterior projection images obtained during SPECT frequently identifies patients with CAD, but it may not provide supplementary information regarding the extent of myocardial ischemia or ventricular dysfunction

  19. Time sequential single photon emission computed tomography studies in brain tumour using thallium-201

    International Nuclear Information System (INIS)

    Ueda, Takashi; Kaji, Yasuhiro; Wakisaka, Shinichiro; Watanabe, Katsushi; Hoshi, Hiroaki; Jinnouchi, Seishi; Futami, Shigemi

    1993-01-01

    Time sequential single photon emission computed tomography (SPECT) studies using thallium-201 were performed in 25 patients with brain tumours to evaluate the kinetics of thallium in the tumour and the biological malignancy grade preoperatively. After acquisition and reconstruction of SPECT data from 1 min post injection to 48 h (1, 2, 3, 4, 5, 6, 7, 8, 9, 10 and 15-20 min, followed by 4-6, 24 and 48 h), the thallium uptake ratio in the tumour versus the homologous contralateral area of the brain was calculated and compared with findings of X-ray CT, magnetic resonance imaging, cerebral angiography and histological investigations. Early uptake of thallium in tumours was related to tumour vascularity and the disruption of the blood-brain barrier. High and rapid uptake and slow reduction of thallium indicated a hypervascular malignant tumour; however, high and rapid uptake but rapid reduction of thallium indicated a hypervascular benign tumour, such as meningioma. Hypovascular and benign tumours tended to show low uptake and slow reduction of thallium. Long-lasting retention or uptake of thallium indicates tumour malignancy. (orig.)

  20. Critical examination of the uniformity requirements for single-photon emission computed tomography.

    Science.gov (United States)

    O'Connor, M K; Vermeersch, C

    1991-01-01

    It is generally recognized that single-photon emission computed tomography (SPECT) imposes very stringent requirements on gamma camera uniformity to prevent the occurrence of ring artifacts. The purpose of this study was to examine the relationship between nonuniformities in the planar data and the magnitude of the consequential ring artifacts in the transaxial data, and how the perception of these artifacts is influenced by factors such as reconstruction matrix size, reconstruction filter, and image noise. The study indicates that the relationship between ring artifact magnitude and image noise is essentially independent of the acquisition or reconstruction matrix sizes, but is strongly dependent upon the type of smoothing filter applied during the reconstruction process. Furthermore, the degree to which a ring artifact can be perceived above image noise is dependent on the size and location of the nonuniformity in the planar data, with small nonuniformities (1-2 pixels wide) close to the center of rotation being less perceptible than those further out (8-20 pixels). Small defects or nonuniformities close to the center of rotation are thought to cause the greatest potential corruption to tomographic data. The study indicates that such may not be the case. Hence the uniformity requirements for SPECT may be less demanding than was previously thought.

  1. Single photon emission computed tomography and albumin colloid imaging of the liver

    International Nuclear Information System (INIS)

    Croft, B.Y.; Teates, C.D.; Honeyman, J.C.

    1984-01-01

    A single photon emission computed tomography (ECT) system using the GE 400T Anger camera with 37 PM tubes and the SPETS software has been installed in our clinical laboratory. It has been used in the study of liver imaging with Tc-99m albumin colloid and other agents. The object of the study is to define what improvement in liver diagnosis might be made using ECT. Patients were injected with 3-4 mCi (ca 120 MBq) of colloid; five standard liver-spleen views and a 64-image ECT study were acquired. The ECT images were acquired either in a circle of the radius of the longer transverse axis of the patient or in an ellipse to match the patient contour. Studies were corrected for the attenuation of the Tc-99m gamma rays by tissue. A series of normal and abnormal patients have been studied and the data analyzed. The significant change in the technique of ECT imaging is the elliptical motion of the camera head which allows a better approximation of the patient contour and improves the spatial resolution of the images. (orig.)

  2. Evaluation of myocardial involvement in muscular dystrophy with thallium-201 emission computed tomography

    International Nuclear Information System (INIS)

    Yamamoto, Shuhei; Sotobata, Iwao; Indo, Toshikatsu; Matsuoka, Yukihiko; Kawai, Naoki; Matsushima, Hideo; Suzuki, Akio; Abe, Tetsutaro; Sakuma, Sadayuki

    1986-01-01

    The clinical usefulness of thallium-201 myocardial perfusion scanning with emission computed tomography (ECT) for evaluation of left ventricular myocardial fibrosis was assessed on 47 patients with Duchenne (DMD), facioscapulohumeral (FSH), limb-girdle (LG) and myotonic (MT) dystrophy. Trans-, long- and short-axial images were interpreted quantitatively by circumferential profile analysis, and the fibrotic tissue size (%FIB) was estimated by integration of hypoperfused areas in 6 to 8 consecutive short-axial slices. Lung/mediastinum count ratios (L/M ratio), LV cavity dilatation, aneurysm formation and cardiac malrotations were also assessed with ECT. Distinct ECT perfusion defect was observed in 26 of 29 DMDs, and in 11 of 18 patients with other types. Perfusion defect was demonstrated in 95 of total 235 segments, and was observed specifically in the posterior wall (82 %) and the apex (65 %) in DMD, and was scattered in all LV wall segments in FSH, LG, and MT. Percent FIB correlated significantly with L/M ratio (r = 0.82, p < 0.01), and did not with age or clinical stage score. ECT showed marked LV dilatation in 7, apical aneurysm in 5 and cardiac malrotation in 23 of the 47 patients. In conclusion, ECT was considered to be a useful clinical means of evaluating myocardial involvement in patients with muscular dystrophy. (author)

  3. Evaluation of myocardial involvement in muscular dystrophy with Thallium-201 emission computed tomography

    International Nuclear Information System (INIS)

    Yamamoto, S.; Kawai, N.; Matsushima, H.; Okada, M.; Yamauchi, K.; Yokota, M.; Hayashi, H.; Sotobata, I.; Sakuma, S.

    1985-01-01

    The clinical usefulness of quantitative analysis of thallium-201 emission computed tomography (ECT) for evaluation of left ventricular myocardial fibrosis was assessed on 45 patients with Duchenne(D), facioscapulohumeral(FSH), limbgirdle(LG) and myotonic(M) dystrophy. Trans-,long- and short-axial images were interpreted quantitatively using circumferential profile analysis, and the fibrotic tissue size (%FIB) was estimated by integration of hypoperfused areas in 6 to 8 consecutive short-axial slices. Lung/mediastinum count ratios (L/M ratio) were also assessed. Distinct ECT defects were found in 42 patients (all cases of D, FSH and LG, and 2 of 5 MTs). ECT defects were observed specifically in the posterolateral wall (71%) and apex (58%) in D, and were scattered in all LV walls in FSHG, LG and MT. ECG and VCG underestimated the extent of myocardial fibrosis in 17 patients (40%). Percent FIBs coincided with fibrotic tissue sizes proven by autopsy. Body-surface ECG should be influenced by cardiac position and rotation in the thorax, which were often observed in these disease entities. These factors were also assessed with ECT. The authors conclude; ECT to be useful for non-invasive evaluation of myocardial fibrosis in patients with various types of muscular dystrophy

  4. Bone single photon emission computed tomography (SPECT in a patient with Pancoast tumor: a case report

    Directory of Open Access Journals (Sweden)

    Hamid Javadi

    Full Text Available CONTEXT: Non-small cell lung carcinomas (NSCLCs of the superior sulcus are considered to be the most challenging type of malignant thoracic disease. In this disease, neoplasms originating mostly from the extreme apex of the lung expand to the chest wall and thoracic inlet structures. Multiple imaging procedures have been applied to identify tumors and to stage and predict tumor resectability in surgical operations. Clinical examinations to localize pain complaints in shoulders and down the arms, and to screen for Horner's syndrome and abnormalities seen in paraclinical assessments, have been applied extensively for differential diagnosis of superior sulcus tumors. Although several types of imaging have been utilized for diagnosing and staging Pancoast tumors, there have been almost no reports on the efficiency of whole-body bone scans (WBBS for detecting the level of abnormality in cases of superior sulcus tumors. CASE REPORT: We describe a case of Pancoast tumor in which technetium-99m methylene diphosphonate (Tc-99m MDP bone single-photon emission-computed tomography (SPECT was able to accurately detect multiple areas of abnormality in the vertebrae and ribs. In describing this case, we stress the clinical and diagnostic points, in the hope of stimulating a higher degree of suspicion and thereby facilitating appropriate diagnosis and treatment. From the results of this study, further clinical trials to evaluate the potential of SPECT as an efficient imaging tool for the work-up on cases of Pancoast tumor are recommended.

  5. [Restoration filtering based on projection power spectrum for single-photon emission computed tomography].

    Science.gov (United States)

    Kubo, N

    1995-04-01

    To improve the quality of single-photon emission computed tomographic (SPECT) images, a restoration filter has been developed. This filter was designed according to practical "least squares filter" theory. It is necessary to know the object power spectrum and the noise power spectrum. The power spectrum is estimated from the power spectrum of a projection, when the high-frequency power spectrum of a projection is adequately approximated as a polynomial exponential expression. A study of the restoration with the filter based on a projection power spectrum was conducted, and compared with that of the "Butterworth" filtering method (cut-off frequency of 0.15 cycles/pixel), and "Wiener" filtering (signal-to-noise power spectrum ratio was a constant). Normalized mean-squared errors (NMSE) of the phantom, two line sources located in a 99mTc filled cylinder, were used. NMSE of the "Butterworth" filter, "Wiener" filter, and filtering based on a power spectrum were 0.77, 0.83, and 0.76 respectively. Clinically, brain SPECT images utilizing this new restoration filter improved the contrast. Thus, this filter may be useful in diagnosis of SPECT images.

  6. Intelligence quotient-adjusted memory impairment is associated with abnormal single photon emission computed tomography perfusion.

    Science.gov (United States)

    Rentz, Dorene M; Huh, Terri J; Sardinha, Lisa M; Moran, Erin K; Becker, John A; Daffner, Kirk R; Sperling, Reisa A; Johnson, Keith A

    2007-09-01

    Cognitive reserve among highly intelligent older individuals makes detection of early Alzheimer's disease (AD) difficult. We tested the hypothesis that mild memory impairment determined by IQ-adjusted norms is associated with single photon emission computed tomography (SPECT) perfusion abnormality at baseline and predictive of future decline. Twenty-three subjects with a Clinical Dementia Rating (CDR) score of 0, were reclassified after scores were adjusted for IQ into two groups, 10 as having mild memory impairments for ability (IQ-MI) and 13 as memory-normal (IQ-MN). Subjects underwent cognitive and functional assessments at baseline and annual follow-up for 3 years. Perfusion SPECT was acquired at baseline. At follow-up, the IQ-MI subjects demonstrated decline in memory, visuospatial processing, and phonemic fluency, and 6 of 10 had progressed to a CDR of 0.5, while the IQ-MN subjects did not show decline. The IQ-MI group had significantly lower perfusion than the IQ-MN group in parietal/precuneus, temporal, and opercular frontal regions. In contrast, higher perfusion was observed in IQ-MI compared with IQ-MN in the left medial frontal and rostral anterior cingulate regions. IQ-adjusted memory impairment in individuals with high cognitive reserve is associated with baseline SPECT abnormality in a pattern consistent with prodromal AD and predicts subsequent cognitive and functional decline.

  7. Regional cerebral blood flow analysis of vascular dementia by the single photon emission computed tomography

    International Nuclear Information System (INIS)

    Miyakawa, Kouichi; Watanabe, Sho; Suzuki, Michiyo; Kamijima, Gonbei

    1989-01-01

    In order to evaluate the relationship between the regional cerebral blood flow (CBF) and cerebrovascular dementia, eleven patients with vascular dementia and eight patients with non-demented infarction were studied and regional CBF were measured quantitatively with single photon emission computed tomography (SPECT) by using N-isopropyl-p-(I-123) iodoamphetamine. All cases were basal infarction and vascular dementia were diagnosed by less than 21.5 of the Hasegawa's dementia score and more than 7 of Hachinsk's ischemic score. The results of the present study were as follows: (1) Cerebrovascular dementia showed lower mean CBF value compared with non-demented group. (2) Regional CBF of bilateral frontal areas and affected basal ganglia were significantly reduced than occipital area in the dementia group. (3) A comparison of regional CBF and the Hasegawa's dementia score revealed a statistically significant correlation at the bilateral frontal areas in the dementia group. It is possible that measuring the regional CBF quantitatively by IMP-SPECT is useful for clinical analysis of vascular dementia. (author)

  8. The role of single photon emission computed tomography in bone imaging.

    Science.gov (United States)

    Sarikaya, I; Sarikaya, A; Holder, L E

    2001-01-01

    Single photon emission computed tomography (SPECT) of the bone is the second most frequently performed SPECT examination in routine nuclear medicine practice, with cardiac SPECT being the most frequent. Compared with planar scintigraphy, SPECT increases image contrast and improves lesion detection and localization. Studies have documented the unique diagnostic information provided by SPECT, particularly for avascular necrosis of the femoral head, in patients with back pain, for the differential diagnosis between malignant and benign spinal lesions, in the detection of metastatic cancer in the spine, for the diagnosis of temporomandibular joint internal derangement, and for the evaluation of acute and chronic knee pain. Although less rigorously documented, SPECT is being increasingly used in all types of situations that demand more precise anatomic localization of abnormal tracer uptake. The effectiveness of bone SPECT increases with the selection of the proper collimator, which allows one to acquire adequate counts and minimize the patient-to-detector distance. Low-energy, ultrahigh-resolution or high-resolution collimation is preferred over all-purpose collimators. Multihead gamma cameras can increase the counts obtained or shorten acquisition time, making SPECT acquisitions more practical in busy departments and also increasing image quality compared with single-head cameras. Iterative reconstruction, with the use of ordered subsets estimation maximization, provides better quality images than classical filtered back projection algorithms. Three-dimensional image analysis often aids lesion localization.

  9. Exercise-induced silent myocardial ischemia: Evaluation by thallium-201 emission computed tomography

    International Nuclear Information System (INIS)

    Kurata, C.; Sakata, K.; Taguchi, T.; Kobayashi, A.; Yamazaki, N.

    1990-01-01

    Factors associated with silent myocardial ischemia (SMI) during exercise testing were studied by means of thallium-201 emission computed tomography (ECT) in 471 patients. Coronary angiography was done in 290, of whom 167 were found to have significant coronary artery disease (CAD). Exercise-induced ischemia and its severity were defined with ECT. During exercise 108 (62%) of 173 patients with ischemia and 57 (50%) of 115 with ischemia and angiographically documented CAD had no chest pain. One third of the patients showed an inconsistency between scintigraphic ischemia and ischemia ST depression. Age, sex, prior myocardial infarction, and diabetes mellitus were not related to SMI. Patients with SMI had less severe ischemia despite a higher peak double product compared to those with painful ischemia. Among 91 with prior myocardial infarction and exercise-induced ischemia, 51 with periinfarction ischemia had a higher frequency of SMI than did 14 with ischemia remote from the prior infarct zone despite similarities in the severity of ischemia. In conclusion, factors localized within ischemic myocardium such as less severe ischemia or adjacency to a prior infarct made SMI more prevalent

  10. WASTE{_}MGMT: A computer model for calculation of waste loads, profiles, and emissions

    Energy Technology Data Exchange (ETDEWEB)

    Kotek, T.J.; Avci, H.I.; Koebnick, B.L. [Argonne National Lab., IL (United States). Environmental Assessment Div.

    1996-12-01

    Waste{_}MGMT is a computational model developed to provide waste loads, profiles, and emissions for the US Department of Energy`s Waste Management Programmatic Environmental Impact Statement (WP PEIS). The model was developed to account for the considerable variety of waste types and processing alternatives evaluated for the WM PEIS. The model is table-driven, with three types of fundamental waste management data defining the input: (1) waste inventories and characteristics; (2) treatment, storage, and disposal facility characteristics; and (3) alternative definition. The primary output of the model consists of tables of waste loads and contaminant profiles at facilities, as well as contaminant air releases for each treatment and storage facility at each site for each waste stream. The model is implemented in Microsoft{reg_sign} FoxPro{reg_sign} for MS-DOS{reg_sign} version 2.5 and requires a microcomputer with at least a 386 processor and a minimum 6 Mbytes of memory and 10 Mbytes of disk space for temporary storage.

  11. Use of Positron Emission Tomography/Computed Tomography in Radiation Treatment Planning for Lung Cancer

    Directory of Open Access Journals (Sweden)

    Kezban Berberoğlu

    2016-06-01

    Full Text Available Radiotherapy (RT plays an important role in the treatment of lung cancer. Accurate diagnosis and staging are crucial in the delivery of RT with curative intent. Target miss can be prevented by accurate determination of tumor contours during RT planning. Currently, tumor contours are determined manually by computed tomography (CT during RT planning. This method leads to differences in delineation of tumor volume between users. Given the change in RT tools and methods due to rapidly developing technology, it is now more significant to accurately delineate the tumor tissue. F18 fluorodeoxyglucose positron emission tomography/CT (F18 FDG PET/CT has been established as an accurate method in correctly staging and detecting tumor dissemination in lung cancer. Since it provides both anatomic and biologic information, F18 FDG PET decreases interuser variability in tumor delineation. For instance, tumor volumes may be decreased as atelectasis and malignant tissue can be more accurately differentiated, as well as better evaluation of benign and malignant lymph nodes given the difference in FDG uptake. Using F18 FDG PET/CT, the radiation dose can be escalated without serious adverse effects in lung cancer. In this study, we evaluated the contribution of F18 FDG PET/CT for RT planning in lung cancer.

  12. Particle induced X-ray emission-computed tomography analysis of an adsorbent for extraction chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Satoh, Takahiro; Yokoyama, Akihito; Kitamura, Akane; Ohkubo, Takeru; Ishii, Yasuyuki [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, Watanuki-machi 1233, 370-1292 Takasaki (Japan); Takahatake, Yoko; Watanabe, Sou; Koma, Yoshikazu [Nuclear Fuel Cycle Engineering Laboratories, Japan Atomic Energy Agency, Muramatsu 4-33, 319-1194 Tokai-mura (Japan); Kada, Wataru [Graduate School of Science and Technology, Gunma University, Tenjin-machi 1-5-1, 376-8515 Kiryu (Japan)

    2016-03-15

    Nd, which simulates minor actinides (MAs), was used for investigating residual minor actinides produced during the extraction chromatography separation of spent fuel from fast neutron reactors. A cross-sectional distribution of Nd in a minute globular adsorbent having diameter less than 50 μm was obtained using particle induced X-ray emission-computed tomography with a 3-MeV proton microbeam. The measurement area was 150 × 150 μm{sup 2} corresponding to 128 × 128 imaging pixels in projection images with 9° resolution, image reconstruction was carried out by a modified ML-EM (maximum likelihood expectation maximization) method. As a result, the cross-sectional distribution of Nd in the adsorbent was successfully obtained, and it was first revealed that Nd existed both in the central region and on the outer surface even after an elution. This implies that the internal structure of the adsorbent must be modified for improving of the recovery of MAs.

  13. Pattern evoked cortical potential topography and positron emission computed tomography in cases with homonymous quadrantanopsia

    International Nuclear Information System (INIS)

    Kakisu, Yonetsugu; Adachi-Usami, Emiko; Kuroda, Noriko; Kawamura, Mitsuru; Yamazaki, Toshiro.

    1985-01-01

    Pattern evoked cortical potentials (PVECPs) and positron emission computed tomography (PET) were studied in two cases with lower homonymous quadrantanopsia caused by occlusion or hemorrhages of the artery of the optic radiation. Using 15 O 2 and C 15 O 2 as a tracer, PET was performed at rest under opened eye stimulation on 6 cm and 8 cm transverse section above the orbito-meatal line. On OM-6 level where the visual cortex of right and left hemisphere received the upper visual field information, symmetrical images of 15 O 2 and C 15 O 2 uptake were found. However, they were lateralized at the non-affected hemisphere in the images of OM-8 level, which corresponded to the anatomical lesion. The PVECP topogram recorded to the stimulation of the right and left lower quadrant visual field was studied by a 16 channel recording system. The positive maxima at the peak latency of P100 were found only at the non-affected hemisphere. It was, thus, proved that PVECP topogram and PET findings could demonstrate the functional abnormalities of the visual cortex in accordance with visual field defect measured by subjective perimetry. (author)

  14. Brain blood flow studies with single photon emission computed tomography in patients with plateau waves

    International Nuclear Information System (INIS)

    Hayashi, Minoru; Kobayashi, Hidenori; Kawano, Hirokazu; Handa, Yuji; Noguchi, Yoshiyuki; Shirasaki, Naoki; Hirose, Satoshi

    1986-01-01

    The authors studied brain blood flow with single photon emission computed tomography (SPECT) in two patients with plateau waves. The intracranial pressure and blood pressure were also monitored continuously in these patients. They included one patient with brain-tumor (rt. sphenoid ridge meningioma) and another with hydrocephalus after subarachnoid hemorrhage due to rupture of lt. internal carotid aneurysm. The intracranial pressure was monitored through an indwelling ventricular catheter attached to a pressure transducer. The blood pressure was recorded through an intraarterial catheter placed in the dorsalis pedis artery. Brain blood flow was studied with Headtome SET-011 (manufactured by Shimazu Co., Ltd.). For this flow measurement study, an intravenous injection of Xenon-133 of about 30 mCi was given via an antecubital vein. The position of the slice for the SPECT was selected so as to obtain information not only from the cerebral hemisphere but also from the brain stem : a cross section 25 deg over the orbito-meatal line, passing through the inferior aspect of the frontal horn, the basal ganglia, the lower recessus of the third ventricle and the brain stem. The results indicated that, in the cerebral hemisphere, plateau waves were accompanied by a decrease in blood flow, whereas, in the brain stem, the blood flow showed little change during plateau waves as compared with the interval phase between two plateau waves. These observations may explain why there is no rise in the blood pressure and why patients are often alert during plateau waves. (author)

  15. Estimation of 99mTc-dimercaptosuccinic acid renal uptake using single photon emission computed tomography

    International Nuclear Information System (INIS)

    Ohishi, Yukihiko; Machida, Toyohei; Kido, Akira

    1986-01-01

    Renal function was assessed by measurement of 99m Tc-dimercaptosuccinic acid (DMSA) uptake by the kidney based on the transectional tomographic image obtained by single photon emission computed tomography (SPECT). The renal uptake was expressed as percentage of the total radioactivity detected in the kidney, the volume of which was measured by convolution method, against the amount dosed. Absorption was corrected by GE-STAR method using cut off level of 42 %. In order to determine normal range, measurement was made for 40 kidneys of each of 10 male and female volunteers confirmed of having normal kidneys both morphologically and functionally. The average volume of the kidney was 220.4 ml for the right and 239.3 ml for the left for males, and 205.9 ml and 236.5 ml, respectively for females. The renal uptake of radioactivity (at 2 h after injection), was 26.8 % for the right and 27.6 % for the left for males, with corresponding figures for females being 26.4 % and 27.9 %, respectively. Distribution range of renal volume and renal uptake was obtained by bivariate analysis with 90 % and 95 % probability. From these results, our method of renal function determination based on renal uptake of 99m Tc-DMSA obtained from renal transactional tomogram by SPECT is considered to be accurate and potentially useful for clinical purpose. (author)

  16. Stress scintigraphy using single-photon emission computed tomography in the evaluation of coronary artery disease

    International Nuclear Information System (INIS)

    Nohara, R.; Kambara, H.; Suzuki, Y.; Tamaki, S.; Kadota, K.; Kawai, C.; Tamaki, N.; Torizuka, K.

    1984-01-01

    Twenty-seven patients with angina pectoris, 24 with postmyocardial infarction angina and 7 with normal coronary arteries were examined by exercise thallium-201 emission computed tomography (SPECT) and planar scintigraphy. Exercise SPECT was compared with the reperfusion imaging obtained approximately 2 to 3 hours after exercise. The sensitivity and specificity of demonstrating involved coronary arteries by identifying the locations of myocardial perfusion defects were 96 and 87% for right coronary artery, 88 and 89% for left anterior descending artery (LAD) and 78 and 100% for left circumflex artery (LC). These figures are higher than those for planar scintigraphy (85 and 87% for right coronary artery, 73 and 89% for LAD and 39 and 100% for LC arteries). In patients with 3-vessel disease, sensitivity of SPECT (100, 88 and 75% for right coronary artery, LAD and LC, respectively) was higher than planar imaging (88, 63 and 31%, respectively), with a significant difference for LC (p less than 0.05). In 1, 2 and 0-vessel disease the sensitivity and specificity of the 2 techniques were comparable. Multivessel disease was more easily identified as multiple coronary involvement than planar imaging with a significant difference in 3-vessel disease (p less than 0.05). In conclusion, stress SPECT provides useful information for the identification of LC lesions in coronary heart disease, including 3-vessel involvement

  17. Estimation of myocardial viability and clinical significance of reverse redistribution in resting technetium-99m sestamibi myocardial single photon emission computed tomography in patients with acute myocardial infarction

    International Nuclear Information System (INIS)

    Itagane, Hiroshi; Otsuka, Masato; Suto, Yayoi; Kajiwara, Kenji; Naruko, Takahiko; Tojo, Osamu; Okumachi, Fukumaru; Haze, Kazuo; Yamagishi, Hiroyuki.

    1997-01-01

    The clinical significance of reverse redistribution of Tc-99m sestamibi (MIBI) was investigated in 36 patients with acute myocardial infarction and angiographically confirmed single-vessel disease, but without previous infarction using resting MIBI myocardial SPECT and exercise-reinjection Tl-201 (Tl) myocardial SPECT. MIBI myocardial SPECT was performed 90 min and 300 min after injection of MIBI 370 MBq at rest. Four hours after exercise Tl imaging was completed, reinjection imaging was obtained. Wall motion abnormalities on left ventriculograms were analyzed at the onset of infarction and 1 month later. The severity scores on the MIBI early image, MIBI delayed image and Tl reinjection image were 98±18, 170±22 and 90±18, respectively. The reverse redistribution of MIBI was marked in acute infarction. A significant correlation of severity score was found between the MIBI early image and Tl reinjection image. In 18 patients with significant stenosis of an infarct-related artery, there was a significant correlation between the degree of reverse redistribution and that of Tl redistribution. A good correlation was found between the severity score on the MIBI early image and wall motion abnormality at 1 month after infarction. There was a significant correlation between the degree of reverse redistribution and wall motion improvement. Despite stenosis of the infarct-related artery, the wall motion abnormality was less in 22 patients with marked reverse redistribution than the other 14 patients. (K.H.)

  18. Low-Computation Strategies for Extracting CO2 Emission Trends from Surface-Level Mixing Ratio Observations

    Science.gov (United States)

    Shusterman, A.; Kim, J.; Lieschke, K.; Newman, C.; Cohen, R. C.

    2017-12-01

    Global momentum is building for drastic, regulated reductions in greenhouse gas emissions over the coming decade. With this increasing regulation comes a clear need for increasingly sophisticated monitoring, reporting, and verification (MRV) strategies capable of enforcing and optimizing emissions-related policy, particularly as it applies to urban areas. Remote sensing and/or activity-based emission inventories can offer MRV insights for entire sectors or regions, but are not yet sophisticated enough to resolve unexpected trends in specific emitters. Urban surface monitors can offer the desired proximity to individual greenhouse gas sources, but due to the densely-packed nature of typical urban landscapes, surface observations are rarely representative of a single source. Most previous efforts to decompose these complex signals into their contributing emission processes have involved inverse atmospheric modeling techniques, which are computationally intensive and believed to depend heavily on poorly understood a priori estimates of error covariance. Here we present a number of transparent, low-computation approaches for extracting source-specific emissions estimates from signals with a variety of nearfield influences. Using observations from the first several years of the BErkeley Atmospheric CO2 Observation Network (BEACO2N), we demonstrate how to exploit strategic pairings of monitoring "nodes," anomalous wind conditions, and well-understood temporal variations to hone in on specific CO2 sources of interest. When evaluated against conventional, activity-based bottom-up emission inventories, these strategies are seen to generate quantitatively rigorous emission estimates. With continued application as the BEACO2N data set grows in time and space, these approaches offer a promising avenue for optimizing greenhouse gas mitigation strategies into the future.

  19. Motor Vehicle Emission Modeling and Software Simulation Computing for Roundabout in Urban City

    Directory of Open Access Journals (Sweden)

    Haiwei Wang

    2013-01-01

    Full Text Available In urban road traffic systems, roundabout is considered as one of the core traffic bottlenecks, which are also a core impact of vehicle emission and city environment. In this paper, we proposed a transport control and management method for solving traffic jam and reducing emission in roundabout. The platform of motor vehicle testing system and VSP-based emission model was established firstly. By using the topology chart of the roundabout and microsimulation software, we calculated the instantaneous emission rates of different vehicle and total vehicle emissions. We argued that Integration-Model, combing traffic simulation and vehicle emission, can be performed to calculate the instantaneous emission rates of different vehicle and total vehicle emissions at the roundabout. By contrasting the exhaust emissions result between no signal control and signal control in this area at the rush hour, it draws a conclusion that setting the optimizing signal control can effectively reduce the regional vehicle emission. The proposed approach has been submitted to a simulation and experiment that involved an environmental assessment in Satellite Square, a roundabout in medium city located in China. It has been verified that setting signal control with knowledge engineering and Integration-Model is a practical way for solving the traffic jams and environmental pollution.

  20. Degenerative dementia: nosological aspects and results of single photon emission computed tomography; Les demences degeneratives: aspects nosologiques et resultats de la tomographie d'emission monophotonique

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, B.; Habert, M.O. [Hopital Pitie-Salpetriere, 75 - Paris (France)

    1999-12-01

    Ten years ago, the diagnosis discussion of a dementia case for the old patient was limited to two pathologies: the Alzheimer illness and the Pick illness. During these last years, the frame of these primary degenerative dementia has fallen into pieces. The different diseases and the results got with single photon emission computed tomography are discussed. for example: fronto-temporal dementia, primary progressive aphasia, progressive apraxia, visio-spatial dysfunction, dementia at Lewy's bodies, or cortico-basal degeneration. (N.C.)

  1. Whole-body magnetic resonance imaging and positron emission tomography-computed tomography in oncology.

    Science.gov (United States)

    Schmidt, Gerwin P; Kramer, Harald; Reiser, Maximilian F; Glaser, Christian

    2007-06-01

    The advent of positron emission tomography-computed tomography (PET-CT) and whole-body magnetic resonance imaging (WB-MRI) has introduced tumor imaging with a systemic and functional approach compared with established sequential, multimodal diagnostic algorithms.Whole-body PET with [18F]-fluoro-2-desoxy-glucose is a useful imaging procedure for tumor staging and monitoring that can visualize active tumor tissue by detecting pathological glucose metabolism. The combination of PET with the detailed anatomical information of multislice computed tomography as dual-modality scanners has markedly increased lesion localization and diagnostic accuracy compared with both modalities as standalone applications.Hardware innovations, such as the introduction of multi-receiver channel whole-body MRI scanners at 1.5 and, recently, 3 T, combined with acquisition acceleration techniques, have made high-resolution WB-MRI clinically feasible. Now, a dedicated assessment of individual organs with various soft tissue contrast, spatial resolution, and contrast media dynamics can be combined with whole-body anatomical coverage in a multiplanar imaging approach. More flexible protocols (eg, T1-weighted turbo spin-echo and short inversion recovery imaging, dedicated lung imaging or dynamic contrast-enhanced studies of the abdomen) can be performed within 45 minutes.Whole-body magnetic resonance imaging has recently been proposed for tumor screening of asymptomatic individuals, and potentially life-changing diagnoses, such as formerly unknown malignancy, have been reported. However, larger patient cohort studies will have to show the cost efficiency and the clinical effectiveness of such an approach.For initial tumor staging, PET-CT has proved more accurate for the definition of T-stage and lymph node assessment, mainly because of the missing metabolic information in WB-MRI. However, new applications, such as magnetic resonance whole-body diffusion-weighted imaging or lymphotropic contrast

  2. Role of Positron Emission Tomography-Computed Tomography in the Management of Anal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Mistrangelo, Massimiliano, E-mail: mistrangelo@katamail.com [Digestive and Colorectal Surgical Department, Centre of Minimal Invasive Surgery, University of Turin, Molinette Hospital, Turin (Italy); Pelosi, Ettore [PET Center IRMET spa, Turin (Italy); Bello, Marilena [Department of Nuclear Medicine, University of Turin, Molinette Hospital (Italy); Ricardi, Umberto [Department of Radiotherapy, University of Turin, Molinette Hospital (Italy); Milanesi, Enrica [Oncological Centre for Gastrointestinal Neoplasms, University of Turin, Molinette Hospital (Italy); Cassoni, Paola [Department of Biomedical Sciences and Human Oncology, University of Turin, Molinette Hospital (Italy); Baccega, Massimo [Department of Nuclear Medicine, Molinette Hospital (Italy); Filippini, Claudia [Anaesthesia and Intensive Care Unit, University of Turin, Molinette Hospital (Italy); Racca, Patrizia [Oncological Centre for Gastrointestinal Neoplasms, University of Turin, Molinette Hospital (Italy); Lesca, Adriana [Department of Nuclear Medicine, Molinette Hospital (Italy); Munoz, Fernando H. [Department of Radiotherapy, University of Turin, Molinette Hospital (Italy); Fora, Gianluca [Oncological Centre for Gastrointestinal Neoplasms, University of Turin, Molinette Hospital (Italy); Skanjeti, Andrea [Department of Nuclear Medicine, University of Turin, Molinette Hospital (Italy); Cravero, Francesca; Morino, Mario [Digestive and Colorectal Surgical Department, Centre of Minimal Invasive Surgery, University of Turin, Molinette Hospital, Turin (Italy)

    2012-09-01

    Purpose: Pre- and post-treatment staging of anal cancer are often inaccurate. The role of positron emission tomograpy-computed tomography (PET-CT) in anal cancer is yet to be defined. The aim of the study was to compare PET-CT with CT scan, sentinel node biopsy results of inguinal lymph nodes, and anal biopsy results in staging and in follow-up of anal cancer. Methods and Materials: Fifty-three consecutive patients diagnosed with anal cancer underwent PET-CT. Results were compared with computed tomography (CT), performed in 40 patients, and with sentinel node biopsy (SNB) (41 patients) at pretreatment workup. Early follow-up consisted of a digital rectal examination, an anoscopy, a PET-CT scan, and anal biopsies performed at 1 and 3 months after the end of treatment. Data sets were then compared. Results: At pretreatment assessment, anal cancer was identified by PET-CT in 47 patients (88.7%) and by CT in 30 patients (75%). The detection rates rose to 97.9% with PET-CT and to 82.9% with CT (P=.042) when the 5 patients who had undergone surgery prior to this assessment and whose margins were positive at histological examination were censored. Perirectal and/or pelvic nodes were considered metastatic by PET-CT in 14 of 53 patients (26.4%) and by CT in 7 of 40 patients (17.5%). SNB was superior to both PET-CT and CT in detecting inguinal lymph nodes. PET-CT upstaged 37.5% of patients and downstaged 25% of patients. Radiation fields were changed in 12.6% of patients. PET-CT at 3 months was more accurate than PET-CT at 1 month in evaluating outcomes after chemoradiation therapy treatment: sensitivity was 100% vs 66.6%, and specificity was 97.4% vs 92.5%, respectively. Median follow-up was 20.3 months. Conclusions: In this series, PET-CT detected the primary tumor more often than CT. Staging of perirectal/pelvic or inguinal lymph nodes was better with PET-CT. SNB was more accurate in staging inguinal lymph nodes.

  3. Relationship of computed tomography perfusion and positron emission tomography to tumour progression in malignant glioma

    International Nuclear Information System (INIS)

    Yeung, Timothy P C; Yartsev, Slav; Lee, Ting-Yim; Wong, Eugene; He, Wenqing; Fisher, Barbara; VanderSpek, Lauren L; Macdonald, David; Bauman, Glenn

    2014-01-01

    Introduction: This study aimed to explore the potential for computed tomography (CT) perfusion and 18-Fluorodeoxyglucose positron emission tomography (FDG-PET) in predicting sites of future progressive tumour on a voxel-by-voxel basis after radiotherapy and chemotherapy. Methods: Ten patients underwent pre-radiotherapy magnetic resonance (MR), FDG-PET and CT perfusion near the end of radiotherapy and repeated post-radiotherapy follow-up MR scans. The relationships between these images and tumour progression were assessed using logistic regression. Cross-validation with receiver operating characteristic (ROC) analysis was used to assess the value of these images in predicting sites of tumour progression. Results: Pre-radiotherapy MR-defined gross tumour; near-end-of-radiotherapy CT-defined enhancing lesion; CT perfusion blood flow (BF), blood volume (BV) and permeability-surface area (PS) product; FDG-PET standard uptake value (SUV); and SUV:BF showed significant associations with tumour progression on follow-up MR imaging (P < 0.0001). The mean sensitivity (±standard deviation), specificity and area under the ROC curve (AUC) of PS were 0.64 ± 0.15, 0.74 ± 0.07 and 0.72 ± 0.12 respectively. This mean AUC was higher than that of the pre-radiotherapy MR-defined gross tumour and near-end-of-radiotherapy CT-defined enhancing lesion (both AUCs = 0.6 ± 0.1, P ≤ 0.03). The multivariate model using BF, BV, PS and SUV had a mean AUC of 0.8 ± 0.1, but this was not significantly higher than the PS only model. Conclusion: PS is the single best predictor of tumour progression when compared to other parameters, but voxel-based prediction based on logistic regression had modest sensitivity and specificity

  4. Role of positron emission tomography-computed tomography in endometrial cancer

    Science.gov (United States)

    Erdemoğlu, Evrim; Çerçi, Sevim Süreyya; Erdemoğlu, Ebru; Yalçın, Yakup; Tatar, Burak

    2017-01-01

    Objective: The efficacy of preoperative 18F-fluoro-D-glucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) in endometrium cancer is controversial. We examined the efficacy of PET-CT and the association between maximum standardized uptake value (SUVmax) and prognostic factors in endometrial cancer. Materials and Methods: Thirty patients with endometrial cancer underwent preoperative 18F-FDG/PET-CT. The patients were treated with abdominal hysterectomy with bilateral salpingo-oophorectomy, and bilateral systemic pelvic lymphadenectomy was planned for all patients; paraaortic lymphadenectomy was performed in patients with intermediate and high risk. Tumor histology, grade, depth of myometrial invasion, maximum tumor diameter, lymphovascular invasion, nodal status, and ovarian/adnexal metastases were recorded. Results: The mean primary tumor diameter was reported smaller in PET-CT and the effect size of PET-CT was -0.60. The kappa value was 0.06 for myometrial invasion. Pelvic lymph node metastasis was reported in 22.2% of patients in PET-CT. However, 3.7% of patients had pelvic lymph node metastasis. The kappa value for pelvic lymph node metastasis was 0.23, and sensitivity, specificity, and positive and negative predictive values were 100%, 80.7%, 16.6%, and 100%, respectively. Paraaortic lymph node metastasis in PET-CT was suspected in 10%. However, paraaortic lymph node metastasis was found in 6.7% in histopathologic analyses. The kappa value was 0.15. The sensitivity, specificity, and positive and negative predictive values of PET-CT for detecting paraaortic lymph node metastases were 100%, 93.7%, 66.6%, and 100%, respectively. Myometrial invasion and tumor diameter were the only important prognostic factors affecting SUVmax. Conclusion: According to our results, PET-CT has a limited role and diagnostic efficacy in endometrial cancer. The indications of FDG/PET-CT in endometrium cancer should be studied further and revised. PMID:29379661

  5. Effect of caffeine on ischemia detection by adenosine single-photon emission computed tomography perfusion imaging.

    Science.gov (United States)

    Zoghbi, Gilbert J; Htay, Thien; Aqel, Raed; Blackmon, Linda; Heo, Jaekyeong; Iskandrian, Ami E

    2006-06-06

    The purpose of this research was to study the effect of one cup of coffee taken 1 h before adenosine stress on the results of myocardial perfusion imaging. Caffeine is believed to attenuate the coronary hyperemic response to adenosine by competitive blockade of the A2a receptor. Caffeine is commonly withheld before adenosine single-photon emission computed tomography (SPECT) perfusion imaging so as not to mask ischemia detection. We studied the effect of one 8-oz cup of coffee taken 1 h before adenosine stress in patients who had demonstrable reversible defects on adenosine SPECT perfusion imaging performed while off caffeine. There were 22 men and 8 women, age 64 +/- 9 years. The blood level of caffeine 1 h after intake was 3.1 +/- 1.6 mg/l. There were two patients with ST-segment depression before and one after caffeine intake (p = NS). The summed stress score (SSS) based on 17 segments (scale of 0 to 3, 3 being normal) was 44 +/- 5 before and 45 +/- 5 after caffeine (p = NS). The summed difference score was 3.8 +/- 1.9 before and. 3.9 +/- 2.3 after caffeine (p = NS), reflecting that around 50% of the perfusion abnormality was reversible before and after caffeine. Using polar maps, the perfusion abnormality was 12 +/- 10% at baseline and 12 +/- 10% after caffeine (p = NS) in agreement with SSS. The left ventricular ejection fraction by gated SPECT was 50 +/- 13% at baseline and 51 +/- 13 % after caffeine (p = NS). A cup of coffee does not mask the presence or severity of reversible defects induced by adenosine SPECT imaging.

  6. Effectiveness of revascularization surgery evaluated by proton magnetic resonance spectroscopy and single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Uno, Masaaki; Ueda, Shin; Hondo, Hideki; Matsumoto, Keizo; Harada, Masafumi [Tokushima Univ. (Japan). School of Medicine

    1996-08-01

    Proton magnetic resonance spectroscopy (MRS) and single photon emission computed tomography (SPECT) were used to evaluate chronic ischemic regions in 26 stroke patients before and 1, 3, and 6 months after revascularization surgery. The volume of interest for proton MRS was placed in an area including part of the frontal and temporal opercula, insular cortex, and basal ganglia. Twenty healthy volunteers served as controls for proton MRS. Patients were divided into three groups according to the preoperative proton MRS. Group A (n=12) had significantly lower N-acetylaspartate/choline (NAA/Cho) and N-acetylaspartate/creatine (NAA/Cr) ratios on the operative side compared to those on the contralateral side, and also lower than those in normal subjects. In seven patients in Group A, postoperative serial proton MRS demonstrated no recovery of these ratios on the operative side. However, proton MRS of the other five patients indicated gradual improvement in these ratios on the operative side at 3 to 6 months after surgery, and SPECT indicated an increase in cerebral blood flow on the operative side in four of these five patients. In Group B (n=9), proton MRS and SPECT showed no laterality before revascularization and no remarkable change during the postoperative course. In Group C (n=5), NAA/Cho or NAA/Cr decreased on the contralateral side preoperatively. Two patients showed fluctuating values of NAA/Cho or NAA/Cr during the postoperative period. Serial proton MRS and SPECT Studies may be useful for the evaluation of revascularization surgery on ischemic regions. The efficacy of revascularization surgery on the metabolism may appear gradually within 3-6 months. (author)

  7. Regional cerebral blood flow in status epileptics measured by single photon emission computed tomography (SPECT)

    International Nuclear Information System (INIS)

    Ichiseki, Hajime; Terashi, Akiro; Hamamoto, Makoto; Miyazaki, Tokuzo.

    1995-01-01

    We have performed single photon emission computed tomography (SPECT) with 99m Tc-hexamethylpropylene amineoxime (HM-PAO) to evaluate regional cerebral blood flow (rCBF) in status epileptics (SE) caused by a cerebral vascular accident. In addition, we have discussed the neurophysiology of SE based on the SPECT findings. A total of sixteen patients (5 males and 11 females, average age; 78.2 years old) with SE who were suffering from prolonged consciousness disturbance were investigated. When SPECT was performed in the ictal state, there was a remarkable increase in radio isotope (RI) uptake at the focus which correlated well with EEG findings. However, in other cortical regions, basal ganglia and thalamus, there was a relatively demonstrated decrease in RI uptake compared with that of the focus. Additionally in the interictal state, we found a decrease in RI uptake in the epileptic foci and normal recovery of the RI uptake level in other cerebral regions. We speculate that these characteristic patterns of cerebral blood flow distribution shown by SPECT scans in the ictal state reflect the state of consciousness disturbance due to SE. In general, in the elderly, it is difficult to make a differential diagnosis between prolonged consciousness disturbance due to nonconvulsive SE and other diseases such as cardiovascular diseases, dehydration, metabolic disorder, etc. Nevertheless, nonconvulsive SE causes diffuse cell loss and irreversible brain damage. Therefore the elderly who have suffered from prolonged consciousness disturbance due to SE need an exact diagnosis and immediate medical treatment. When we diagnose a nonconvulsive SE, the characteristic findings of SPECT scans in the ictal state are very clear and useful. In conclusion, SPECT is a very simple and non-invasive method that demonstrates abnormalities of brain function exactly. Therefore, we should perform not only EEC but also SPECT scans when making a diagnosis of SE. (author)

  8. Cerebellar hemangioblastomas with computed tomographic, angiographic, and positron-emission tomographic evaluations

    International Nuclear Information System (INIS)

    Kikuchi, Kenji; Sakamoto, Tetsuya; Kowada, Masayoshi; Tamakawa, Yoshiharu; Uemura, Kazuo.

    1986-01-01

    Ten patients with cerebellar hemangioblastomas were reviewed, and evaluations were made by computed tomography (CT), vertebral angiography, and positron-emission tomography (PET). Cerebellar hemangioblastomas were classified into three types on the basis of their CT appearances: Type I: a cystic tumor without a demonstrable mural nodule; Type II: a cystic tumor with a mural nodule, and Type III: a solid tumor without any cyst formation. All of the cystic tumors classified here as Types I and II were associated with a shift and deformity of the fourth ventricule and an enlarged lateral ventricle, and yet no low-density area in the adjacent cerebellar tissue indicating perifocal edema was demonstrated. By contrast, in the solid hemangioblastomas designated as Type III, finger-shaped, low-density areas were visualized around the enhancing mass lesion, extending to the white matter of the entire affected cerebellar hemisphere. The vertebral angiographic classification of cerebellar hemangioblastomas was also attempted as follows: Type I: an avascular tumor without a demonstrable mural nodule; Type II: an avascular tumor with a mural nodule, and Type III: a solid vascular tumor with enlarged feeding arteries and distinct draining veins. In Type II, a relatively small mural nodule was visualized, fed mostly by a single feeding artery, and the tumor stain was at its peak at the arterial phase. No draining vein was opacified in most cases. In contrast, solid tumors classified as Type III were demonstrated to be hypervascular tumors with a multiplicity of feeding arteries and draining veins. The vascular mass remained to be opacified through the venous phase with delayed blood circulation. PET was performed on a 31-year-old male with a solid hemangioblastoma. (J.P.N)

  9. Emission computed tomography using rotating gamma cameras for stress 201Tl myocardial imaging

    International Nuclear Information System (INIS)

    Takeda, Kan; Maeda, Hisato; Nakagawa, Tsuyoshi; Yamaguchi, Nobuo; Taguchi, Mitsuo

    1983-01-01

    The purpose of this study is to evaluate the efficacy of emission computed tomography (ECT) for stress 201 Tl myocardial imaging to localize coronary artery disease (CAD) in comparison with planar (PL) images. In a series of 14 normal subjects and 53 patients with CAD proved coronary arteriography, ECT and PL imaging were performed successively. ECT data were collected for 90 projections in a 64 x 64 matrix form with a total aquisition time of 6 munutes over 180 0 of opposed dual cameras ratation and tomographic sections oriented perpendicular and parallel to the long axis of left ventricle were reconstructed. PL images were obtained for left lateral, left anterior oblique (30 0 and 45 0 ) and anterior projections. Both ECT and PL myocardial images were divided into 8 segments and segmental analysis was performed by visual interpretation. The ECT images remarkably increased sensitivity over the PL images in left anterior descending (LAD) artery (from 56% to 76%), right coronary artery (RCA) (from 50% to 96%), and circumflex artery (CX) (from 56% to 69%) lesions. The specificity for ECT images, as compared with PL images, was higher in LAD (88% against 85%) but slightly lower in RCA (70% ag ainst 72%) and CX (84% against 88%). Overall accuracy, therefore, was improved in LAD (from 67% to 81%) and RCA (from 64% to 79%) but equal in CX (81%). We conclude that stress 201 Tl ECT imaging result in a remarkable improvement in the localization of CAD, especially in patients with RCA lesions and multi-vessel disease. (author)

  10. Reverse redistribution in dipyridamole-loading thallium-201 images using single photon emission computed tomography

    International Nuclear Information System (INIS)

    Mori, Kiyoo; Masuda, Masanosuke; Bunko, Hisashi.

    1986-01-01

    Dipyridamole was infused intravenously at a rate of 0.142 mg/kg per min for four min, and a stress image was obtained 10 min after the injection of two mCi 201 Tl. The myocardial image of Tl was analyzed by single photon emission computed tomography and its washout rate was calculated by the segmental ROI method. Myocardial function and the motion of the left ventricular wall were analyzed by 99m Tc-RBC-gated cardiac pool imaging. Reverse redistribution was noted in 27 (21.6 %) of 125 consecutive Tl dipyridamole and redistribution myocardial imaging studies. The stress image demonstrated normal perfusion (group 1) and reduced perfusion (group 2) of Tl. Group 1 consisted of 17 patients with diabetes mellitus, supraventricular arrhythmias, hypertension, and others. Group 2 consisted of 10 patients with subendocardial infarction, diabetes mellitus, and hypertension, and others. The percentage prevalence of reverse redistribution among patients with supraventricular arrhythmia was 62.5 % (five of eight patients), with subendocardial infarction 60.0 % (three of five), with hypertension 42.8 % (six of 14), and with diabetes mellitus 40.0 % (eight of 20), while in those with transmyocardial infarction and angina pectoris no reverse redistribution percentage was found. The washout rate of Tl in normal perfusion areas was 44.0 ± 12.8 %, the reverse redistribution of group 1 was 47.4 ± 12.8 %, and of group 2 was 51.2 ± 8.2 %. The washout rate of the reverse redistribution of group 2 was significantly greater than that of the normal areas. In gated cardiac pool imaging, patients in group 2 had significantly larger areas showing abnormal contraction of the left ventricular wall and significantly lower ejection fraction than did group 1. In the electrocardiogram ST segment depression was noted more frequently in group 2 than group 1. No Q wave was present in the corresponding reverse redistribution area. (J.P.N.)

  11. Positron emission tomography combined with computed tomography for diagnosis of synchronous and metachronous tumors

    International Nuclear Information System (INIS)

    Zlatareva, D.; Garcheva, M.; Hadjiiska, V.

    2013-01-01

    Full text: Introduction: Positron emission tomography combined computed tomography (PET/CT) has proved to be the method of choice in oncology for diagnosis and staging, planning and determining the effect of treatment. Aim of the study was to determine the diagnostic capabilities of PET/CT for the detection of synchronous and metachronous tumors. Materials and Methods: The study was conducted with 18F FDG on Discovery, GE Healthcare under standard protocol. 18F FDG is dosed per kg body weight applying before a meal in blood sugar within reference values. The survey was conducted 60 min after application, in addition to visual assessment using quantitative indicators. For a period of a year (2012) 1408 patients were studied. In 11 (2 men, 9 women) of them synchronous and metachronous unsuspected tumors were found. Results: The most common as the second tumors are found processes in the head and neck, followed by lung cancer and colorectal cancer. In four of the cases operational or histological verification was made. In others cases due to refusal or advanced disease indications for systemic therapy the verification wasn't made. Diagnosis of the second tumor has changed the approach to patients as the therapeutic effect was detected at 3 patients over a period of nine months by repeated PET/CT study. Conclusion: The hybrid PET/CT, combining information about structural changes (CT) and metabolic changes (PET) plays an important role in the diagnosis of synchronous and metachronous tumors. This can significantly change the therapeutic management and prognosis of patients

  12. Relationship of computed tomography perfusion and positron emission tomography to tumour progression in malignant glioma

    Energy Technology Data Exchange (ETDEWEB)

    Yeung, Timothy P C [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Robarts Research Institute, The University of Western Ontario, Ontario, Canada, N6A 5B7 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Yartsev, Slav [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Lee, Ting-Yim [Robarts Research Institute, The University of Western Ontario, Ontario, Canada, N6A 5B7 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Department of Medical Imaging, The University of Western Ontario, London Health Sciences Centre, Victoria Hospital, Ontario, Canada, N6A 5W9 (Australia); Lawson Health Research Institute, St. Joseph' s Health Care London, Ontario, Canada, N6A 4V2 (Canada); Wong, Eugene [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Department of Physics and Astronomy, The University of Western Ontario, Ontario, Canada, N6A 3K7 (Canada); He, Wenqing [Department of Statistical and Actuarial Sciences, The University of Western Ontario, Ontario, Canada, N6A 5B7 (Canada); Fisher, Barbara; VanderSpek, Lauren L [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Macdonald, David [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada); Department of Clinical Neurological Sciences, The University of Western Ontario, London Health Sciences Centre, University Hospital, Ontario, Canada, N6A 5A5 (Canada); Bauman, Glenn, E-mail: glenn.bauman@lhsc.on.ca [London Regional Cancer Program, London Health Sciences Centre, Ontario, Canada, N6A 4L6 (Canada); Department of Medical Biophysics, The University of Western Ontario, Ontario, Canada, N6A 5C1 (Canada); Department of Oncology, The University of Western Ontario, London Health Sciences Centre, London Regional Cancer Program, Ontario, Canada, N6A 4L6 (Canada)

    2014-02-15

    Introduction: This study aimed to explore the potential for computed tomography (CT) perfusion and 18-Fluorodeoxyglucose positron emission tomography (FDG-PET) in predicting sites of future progressive tumour on a voxel-by-voxel basis after radiotherapy and chemotherapy. Methods: Ten patients underwent pre-radiotherapy magnetic resonance (MR), FDG-PET and CT perfusion near the end of radiotherapy and repeated post-radiotherapy follow-up MR scans. The relationships between these images and tumour progression were assessed using logistic regression. Cross-validation with receiver operating characteristic (ROC) analysis was used to assess the value of these images in predicting sites of tumour progression. Results: Pre-radiotherapy MR-defined gross tumour; near-end-of-radiotherapy CT-defined enhancing lesion; CT perfusion blood flow (BF), blood volume (BV) and permeability-surface area (PS) product; FDG-PET standard uptake value (SUV); and SUV:BF showed significant associations with tumour progression on follow-up MR imaging (P < 0.0001). The mean sensitivity (±standard deviation), specificity and area under the ROC curve (AUC) of PS were 0.64 ± 0.15, 0.74 ± 0.07 and 0.72 ± 0.12 respectively. This mean AUC was higher than that of the pre-radiotherapy MR-defined gross tumour and near-end-of-radiotherapy CT-defined enhancing lesion (both AUCs = 0.6 ± 0.1, P ≤ 0.03). The multivariate model using BF, BV, PS and SUV had a mean AUC of 0.8 ± 0.1, but this was not significantly higher than the PS only model. Conclusion: PS is the single best predictor of tumour progression when compared to other parameters, but voxel-based prediction based on logistic regression had modest sensitivity and specificity.

  13. Myocardial involvement in muscular dystrophy evaluated by thallium-201 emission computed tomography

    International Nuclear Information System (INIS)

    Yamamoto, Shuhei; Matsushima, Hideo; Kawai, Naoki; Sotobata, Iwao

    1986-01-01

    The clinical usefulness of thallium-201 myocardial emission computed tomography (ECT) for evaluating left ventricular myocardial fibrosis was assessed in 47 patients with Duchenne (MD), facio-scapulo-humeral (FSH), limb-girdle (LG) and myotonic (MT) dystrophy. 1. Trans-, long- and short-axial images were interpreted quantitatively by circumferential profile analysis, and the extent of fibrotic tissue (%FIB) was estimated by integrating hypoperfused areas in six to eight consecutive short-axial slices. Lung/mediastinum count ratio (L/M ratio), LV cavity dilatation, aneurysm formation and cardiac malrotation were also assessed with ECT. 2. Distinct ECT defects were demonstrated in 95 of a total of 235 LV segments (40 %) and in 37 of 47 cases (85 % of DMD, 71 % of FSH, 50 % of MT and 60 % of LG). They were observed specifically in the posterior wall (82 %) and the apex (65 %) in DMD, and were scattered in all LV wall segments in FSH, LG, and MT. 3. There was a significant correlation between %FIB and the L/M ratio (r = 0.79, p < 0.001), and the L/M ratio was significantly higher in DMD than in MT (0.67 ± 0.36 vs 0.34 ± 0.25, p < 0.05). 4. ECT showed marked LV dilatation in seven (15 %), apical aneurysm in five (11 %) and vertical heart in 12 (26 %) of the 47 patients. 5. There were no significant correlations between age or clinical stage scores and numbers of defect segments or %FIB in each group. 6. During the one-year follow-up period of these patients, a DMD boy with the largest %FIB (54 %) and the highest L/M ratio (1.4) together with LV dilatation had complications of refractory heart failure and he died eight months following the ECT examination. 7. Thallium-201 planar imaging and standard 12-lead ECG underestimated the perfusion defects which were evaluated with ECT. (author)

  14. F18-fluorodeoxyglucose-positron emission tomography/computed tomography screening in Li-Fraumeni syndrome.

    Science.gov (United States)

    Masciari, Serena; Van den Abbeele, Annick D; Diller, Lisa R; Rastarhuyeva, Iryna; Yap, Jeffrey; Schneider, Katherine; Digianni, Lisa; Li, Frederick P; Fraumeni, Joseph F; Syngal, Sapna; Garber, Judy E

    2008-03-19

    Individuals with Li-Fraumeni syndrome (LFS) have an inherited cancer predisposition to a diverse array of malignancies beginning early in life; survivors of one cancer have a markedly elevated risk of additional primary tumors. The underlying genetic defect in the majority of the families is a germline mutation in the TP53 tumor suppressor gene. The diversity of tumors and rarity of families have contributed to the difficulty in devising effective screening recommendations for members of LFS kindreds. To gather preliminary data with which to evaluate F18-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) imaging as a potential surveillance modality to detect early malignancies in asymptomatic members of LFS kindreds. Members of LFS families with documented germline TP53 mutations or obligate carrier status, no history of cancer within 5 years of enrollment, and no symptoms of cancer or ill-health were offered FDG-PET/CT scanning as a screening test in a comprehensive US cancer center from 2006 to 2007. Scans were initially reviewed clinically, then centrally reviewed by an expert radiologist. The primary outcome was the detection of new primary cancers using FDG-PET/CT scanning. Of 15 individuals, baseline FDG-PET/CT scan identified asymptomatic cancers in 3 (20%). Two individuals had papillary thyroid cancers (stage II and stage III) and one individual had stage II esophageal adenocarcinoma. These preliminary data provide the first evidence for a potential cancer surveillance strategy that may be worthy of further investigation for patients with LFS. Concerns about radiation exposure and other challenges inherent in screening high-risk patients will require further consideration.

  15. [18F]2-fluoro-2-deoxyglucose positron emission tomography/computed tomography in predicting radiation pneumonitis.

    Science.gov (United States)

    Song, Hao; Yu, Jin-ming; Kong, Feng-ming; Lu, Jie; Bai, Tong; Ma, Li; Fu, Zheng

    2009-06-05

    Prevention is presently the only available method to limit radiation-induced lung morbidity. A good predictor is the key point of prevention. This study aimed to investigate if [(18)F]2-fluoro-2-deoxyglucose (FDG) uptake changes in the lung after radiotherapy could be used as a new predictor for acute radiation pneumonitis (RP). Forty-one patients with lung cancer underwent FDG positron emission tomography/computed tomography (FDG-PET/CT) imaging before and after radiotherapy. The mean standardized uptake value (SUV) was measured for the isodose regions of 0 - 9 Gy, 10 - 19 Gy, 20 - 29 Gy, 30 - 39 Gy, 40 - 49 Gy. The mean SUV of these regions after radiotherapy was compared with baseline. The mean SUV in patients who developed RP was also compared with that in those who did not. The statistical difference was determined by matched pair t test. The Radiation Therapy Oncology Group (RTOG) criteria were used for diagnosis and grading of RP. With a median follow-up of 12 months, 11 (26.8%) of the 41 patients developed grade 2 and above acute RP. The mean SUV of regions (10 - 19 Gy, 20 - 29 Gy, 30 - 39 Gy, 40 - 49 Gy) increased after radiation therapy in all 41 patients. The mean SUVs after radiation therapy were 0.54, 0.68, 1.31, 1.74 and 2.27 for 0 - 9 Gy, 10 - 19 Gy, 20 - 29 Gy, 30 - 39 Gy and 40 - 49 Gy, respectively. Before the radiation therapy, the mean SUV in each region was 0.53, 0.52, 0.52, 0.53 and 0.54, respectively. These patients had significantly higher FDG activities in regions receiving 10 Gy or more (P acute RP subsequently. The mean SUV of the lung tissue may be a useful predictor for the acute RP. FDG-PET/CT may play a new role in the study of the radiation damage of the lung.

  16. Evaluation of regional cerebral circulation and metabolism in moyamoya disease using positron emission computed tomography

    International Nuclear Information System (INIS)

    Kuwabara, Yasuo

    1986-01-01

    Regional cerebral blood flow, oxygen extraction fraction, metabolic rate of oxygen, blood volume and transit time were evaluated in 11 patients with moyamoya disease and 3 with suspected moyamoya disease using positron emission computed tomography. Eight of them were examined before and after EC-IC bypass surgery. Moyamoya patients were classified into four groups, namely, pediatric bilateral chronic type (over 5 years from onset), pediatric bilateral early type (within 5 years from onset), pediatric unilateral early type and adult type, according to age, duration of disease from onset and angiographic findings. These four groups showed different patterns on PET images; diffusely decreased CBF and CMRO2 in pediatric bilateral chronic type, decreased CBF and increased OEF in the frontal or temporoparietal region in pediatric bilateral early type, diffusely decreased CBF and increased OEF in the unilateral cerebral hemisphere in pediatric unilateral cerebral hemisphere in pediatric unilateral early type, and decreased CBF and CMRO2 in adult type. An increase of rCBV was demonstrated in frontal regions or basal ganglia in all groups, more prominently in pediatric patients. This was thought to be a common finding in moyamoya disease, corresponding to moyamoya vessels. Staging of moyamoya disease by PET was presented and compared to the angiographic staging. They were significantly correlated, and the stage 3 on PET image with decreased CMRO2 corresponded to the stage 3 or 4 on angiography, the most active stage of moyamoya disease. PET revealed increased CBF in the cortical area around EC-IC bypass but no remarkable changes in mean values of rCBF, OEF, CMRO2 and CBV in cerebral hemisphere. Some patients showed decreased rCBV in the basal ganglia. (J.P.N.)

  17. Enhancement of positron emission tomography-computed tomography image quality using the principle of stochastic resonance

    International Nuclear Information System (INIS)

    Pandey, Anil Kumar; Sharma, Sanjay Kumar; Sharma, Punit; Singh, Harmandeep; Patel, Chetan; Sarkar, Kaushik; Kumar, Rakesh; Bal, Chandra Sekhar

    2014-01-01

    Acquisition of higher counts improves visual perception of positron emission tomography-computed tomography (PET-CT) image. Larger radiopharmaceutical doses (implies more radiation dose) are administered to acquire this count in a short time period. However, diagnostic information does not increase after a certain threshold of counts. This study was conducted to develop a post processing method based on principle of “stochastic resonance” to improve visual perception of the PET-CT image having a required threshold counts. PET-CT images (JPEG file format) with low, medium, and high counts in the image were included in this study. The image was corrupted with the addition of Poisson noise. The amplitude of the Poisson noise was adjusted by dividing each pixel by a constant 1, 2, 4, 8, 16, and 32. The best amplitude of the noise that gave best images quality was selected based on high value of entropy of the output image, high value of structural similarity index and feature similarity index. Visual perception of the image was evaluated by two nuclear medicine physicians. The variation in structural and feature similarity of the image was not appreciable visually, but statistically images deteriorated as the noise amplitude increases although maintaining structural (above 70%) and feature (above 80%) similarity of input images in all cases. We obtained the best image quality at noise amplitude “4” in which 88% structural and 95% feature similarity of the input images was retained. This method of stochastic resonance can be used to improve the visual perception of the PET-CT image. This can indirectly lead to reduction of radiation dose

  18. Fluorodeoxyglucose positron emission tomography/computed tomography findings in a patient with cerebellar mutism after operation in posterior fossa

    Directory of Open Access Journals (Sweden)

    Gonca Kara Gedik

    2017-03-01

    Full Text Available Cerebellar mutism is a transient period of speechlessness that evolves after posterior fossa surgery in children. Although direct cerebellar and brain stem injury and supratentorial dysfunction have been implicated in the mediation of mutism, the pathophysiological mechanisms involved in the evolution of this kind of mutism remain unclear. Magnetic resonance imaging revealed dentatothalamocortical tract injuries and single photon emission computed tomography showed cerebellar and cerebral hypoperfusion in patients with cerebellar mutism. However, findings with 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT in this group of patients have not been documented previously. In this clinical case, we report a patient who experienced cerebellar mutism after undergoing a posterior fossa surgery. Right cerebellar and left frontal lobe hypometabolism was shown using FDG PET/CT. The FDG metabolism of both the cerebellum and the frontal lobe returned to normal levels after the resolution of the mutism symptoms.

  19. Head and neck: normal variations and benign findings in FDG positron emission tomography/computed tomography imaging.

    Science.gov (United States)

    Højgaard, Liselotte; Berthelsen, Anne Kiil; Loft, Annika

    2014-04-01

    Positron emission tomography (PET)/computed tomography with FDG of the head and neck region is mainly used for the diagnosis of head and neck cancer, for staging, treatment evaluation, relapse, and planning of surgery and radio therapy. This article is a practical guide of imaging techniques, including a detailed protocol for FDG PET in head and neck imaging, physiologic findings, and pitfalls in selected case stories. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. EEG, transmission computed tomography, and positron emission tomography with fluorodeoxyglucose 18F. Their use in adults with gliomas

    International Nuclear Information System (INIS)

    Newmark, M.E.; Theodore, W.H.; Sato, S.; De La Paz, R.; Patronas, N.; Brooks, R.; Jabbari, B.; Di Chiro, G.

    1983-01-01

    We evaluated the relationship between findings from EEG, transmission computed tomography (CT), and positron emission tomography in 23 adults with gliomas. The cortical metabolic rate was suppressed in patients with and without focal slowing. Focal delta activity was not related to involvement of gray or white matter. Rhythmic delta activity and focal attenuation of background amplitude on EEG, however, were correlated with involvement of the thalamus

  1. Retroperitoneal Endometriosis: A Possible Cause of False Positive Finding at 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography

    International Nuclear Information System (INIS)

    Maffione, Anna Margherita; Panzavolta, Riccardo; Lisato, Laura Camilla; Ballotta, Maria; D'Isanto, Mariangela Zanforlini; Rubello, Domenico

    2015-01-01

    Endometriosis is a frequent and clinically relevant problem in young women. Laparoscopy is still the gold standard for the diagnosis of endometriosis, but frequently both morphologic and functional imaging techniques are involved in the diagnostic course before achieving a conclusive diagnosis. We present a case of a patient affected by infiltrating retroperitoneal endometriosis falsely interpreted as a malignant mass by contrast-enhanced magnetic resonance imaging and 18 F-fluorodeoxyglucose positron emission tomography/computed tomography

  2. Positron emission tomography/computed tomography imaging features of renal cell carcinoma and pulmonary metastases in a dog.

    Science.gov (United States)

    Song, Sun-Hye; Park, Noh-Won; Eom, Ki-Dong

    2014-05-01

    A 9-year-old spayed female cocker spaniel dog was referred for hematuria. A large abdominal mass and multiple pulmonary nodules were identified radiographically. A whole-body 2-deoxy-2-[(18)F]fluoro-d-glucose positron emission tomography/computed tomography (PET/CT) scan revealed intensely increased uptake in a renal mass and the pulmonary nodules. Renal cell carcinoma was diagnosed on histological examination.

  3. Positron emission tomography/computed tomography imaging features of renal cell carcinoma and pulmonary metastases in a dog

    OpenAIRE

    Song, Sun-Hye; Park, Noh-Won; Eom, Ki-Dong

    2014-01-01

    A 9-year-old spayed female cocker spaniel dog was referred for hematuria. A large abdominal mass and multiple pulmonary nodules were identified radiographically. A whole-body 2-deoxy-2-[18F]fluoro-d-glucose positron emission tomography/computed tomography (PET/CT) scan revealed intensely increased uptake in a renal mass and the pulmonary nodules. Renal cell carcinoma was diagnosed on histological examination.

  4. Utility of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography in a child with chronic granulomatous disease

    International Nuclear Information System (INIS)

    Garg, Gunjan; DaSilva, Raphaella; Bhalakia, Avni; Milstein, David M.

    2016-01-01

    We report the fluorodeoxyglucose positron emission tomography/computed tomography (FDG - PET/CT) findings in an 11-month-old boy with suspected milk protein allergy, presented to the hospital with 2-month history of fever of unknown origin and failure to thrive. It showed FDG avid lymphadenopathy above and below the diaphragm and splenic focus, which could represent diffuse inflammatory process or lymphoma. Subsequent jejunal biopsy showed non-necrotizing granulomas

  5. In Vivo Treatment Sensitivity Testing With Positron Emission Tomography/Computed Tomography After One Cycle of Chemotherapy for Hodgkin Lymphoma

    DEFF Research Database (Denmark)

    Hutchings, Martin; Kostakoglu, Lale; Zaucha, Jan Maciej

    2014-01-01

    PURPOSE: Negative [(18)F]fluorodeoxyglucose (FDG) -positron emission tomography (PET)/computed tomography (CT) after two cycles of chemotherapy indicates a favorable prognosis in Hodgkin lymphoma (HL). We hypothesized that the negative predictive value would be even higher in patients responding....... In the absence of precise pretherapeutic predictive markers, PET1 is the best method for response-adapted strategies designed to select patients for less intensive treatment....

  6. A Study on GPU-based Iterative ML-EM Reconstruction Algorithm for Emission Computed Tomographic Imaging Systems

    International Nuclear Information System (INIS)

    Ha, Woo Seok; Kim, Soo Mee; Park, Min Jae; Lee, Dong Soo; Lee, Jae Sung

    2009-01-01

    The maximum likelihood-expectation maximization (ML-EM) is the statistical reconstruction algorithm derived from probabilistic model of the emission and detection processes. Although the ML-EM has many advantages in accuracy and utility, the use of the ML-EM is limited due to the computational burden of iterating processing on a CPU (central processing unit). In this study, we developed a parallel computing technique on GPU (graphic processing unit) for ML-EM algorithm. Using Geforce 9800 GTX+ graphic card and CUDA (compute unified device architecture) the projection and backprojection in ML-EM algorithm were parallelized by NVIDIA's technology. The time delay on computations for projection, errors between measured and estimated data and backprojection in an iteration were measured. Total time included the latency in data transmission between RAM and GPU memory. The total computation time of the CPU- and GPU-based ML-EM with 32 iterations were 3.83 and 0.26 sec, respectively. In this case, the computing speed was improved about 15 times on GPU. When the number of iterations increased into 1024, the CPU- and GPU-based computing took totally 18 min and 8 sec, respectively. The improvement was about 135 times and was caused by delay on CPU-based computing after certain iterations. On the other hand, the GPU-based computation provided very small variation on time delay per iteration due to use of shared memory. The GPU-based parallel computation for ML-EM improved significantly the computing speed and stability. The developed GPU-based ML-EM algorithm could be easily modified for some other imaging geometries

  7. Positron emission tomography/computed tomography surveillance in patients with Hodgkin lymphoma in first remission has a low positive predictive value and high costs.

    Science.gov (United States)

    El-Galaly, Tarec Christoffer; Mylam, Karen Juul; Brown, Peter; Specht, Lena; Christiansen, Ilse; Munksgaard, Lars; Johnsen, Hans Erik; Loft, Annika; Bukh, Anne; Iyer, Victor; Nielsen, Anne Lerberg; Hutchings, Martin

    2012-06-01

    The value of performing post-therapy routine surveillance imaging in patients with Hodgkin lymphoma is controversial. This study evaluates the utility of positron emission tomography/computed tomography using 2-[18F]fluoro-2-deoxyglucose for this purpose and in situations with suspected lymphoma relapse. We conducted a multicenter retrospective study. Patients with newly diagnosed Hodgkin lymphoma achieving at least a partial remission on first-line therapy were eligible if they received positron emission tomography/computed tomography surveillance during follow-up. Two types of imaging surveillance were analyzed: "routine" when patients showed no signs of relapse at referral to positron emission tomography/computed tomography, and "clinically indicated" when recurrence was suspected. A total of 211 routine and 88 clinically indicated positron emission tomography/computed tomography studies were performed in 161 patients. In ten of 22 patients with recurrence of Hodgkin lymphoma, routine imaging surveillance was the primary tool for the diagnosis of the relapse. Extranodal disease, interim positron emission tomography-positive lesions and positron emission tomography activity at response evaluation were all associated with a positron emission tomography/computed tomography-diagnosed preclinical relapse. The true positive rates of routine and clinically indicated imaging were 5% and 13%, respectively (P = 0.02). The overall positive predictive value and negative predictive value of positron emission tomography/computed tomography were 28% and 100%, respectively. The estimated cost per routine imaging diagnosed relapse was US$ 50,778. Negative positron emission tomography/computed tomography reliably rules out a relapse. The high false positive rate is, however, an important limitation and a confirmatory biopsy is mandatory for the diagnosis of a relapse. With no proven survival benefit for patients with a pre-clinically diagnosed relapse, the high costs and low

  8. Positron Emission Tomography Computed Tomography: A Guide for the General Radiologist.

    Science.gov (United States)

    Beadsmoore, Clare; Newman, David; MacIver, Duncan; Pawaroo, Davina

    2015-11-01

    Cancer remains a leading cause of death in Canada and worldwide. Whilst advances in anatomical imaging to detect and monitor malignant disease have continued over the last few decades, limitations remain. Functional imaging, such as positron emission tomography (PET), has improved the sensitivity and specificity in detecting malignant disease. In combination with computed tomography (CT), PET is now commonly used in the oncology setting and is an integral part of many cancer patients' pathways. Although initially the CT component of the study was purely for attenuation of the PET imaging and to provide anatomical coregistration, many centers now combine the PET study with a diagnostic quality contrast enhanced CT to provide one stop staging, thus refining the patient's pathway. The commonest tracer used in everyday practice is FDG (F18-fluorodeoxyglucose). There are many more tracers in routine clinical practice and those with emerging roles, such as 11C-choline, useful in the imaging of prostate cancer; 11C-methionine, useful in imaging brain tumours; C11-acetate, used in imaging hepatocellular carcinomas; 18F-FLT, which can be used as a marker of cellular proliferation in various malignancies; and F18-DOPA and various 68Ga-somatostatin analogues, used in patients with neuroendocrine tumours. In this article we concentrate on FDG PETCT as this is the most commonly available and widely utilised tracer now used to routinely stage a number of cancers. PETCT alters the stage in approximately one-third of patients compared to anatomical imaging alone. Increasingly, PETCT is being used to assess early metabolic response to treatment. Metabolic response can be seen much earlier than a change in the size/volume of the disease which is measured by standard CT imaging. This can aid treatment decisions in both in terms of modifying therapy and in addition to providing important prognostic information. Furthermore, it is helpful in patients with distorted anatomy from surgery

  9. Budget impact from the incorporation of positron emission tomography – computed tomography for staging lung cancers

    Directory of Open Access Journals (Sweden)

    Aline Navega Biz

    2015-01-01

    Full Text Available OBJECTIVE To estimate the budget impact from the incorporation of positron emission tomography (PET in mediastinal and distant staging of non-small cell lung cancer.METHODS The estimates were calculated by the epidemiological method for years 2014 to 2018. Nation-wide data were used about the incidence; data on distribution of the disease´s prevalence and on the technologies’ accuracy were from the literature; data regarding involved costs were taken from a micro-costing study and from Brazilian Unified Health System (SUS database. Two strategies for using PET were analyzed: the offer to all newly-diagnosed patients, and the restricted offer to the ones who had negative results in previous computed tomography (CT exams. Univariate and extreme scenarios sensitivity analyses were conducted to evaluate the influence from sources of uncertainties in the parameters used.RESULTS The incorporation of PET-CT in SUS would imply the need for additional resources of 158.1 BRL (98.2 USD million for the restricted offer and 202.7 BRL (125.9 USD million for the inclusive offer in five years, with a difference of 44.6 BRL (27.7 USD million between the two offer strategies within that period. In absolute terms, the total budget impact from its incorporation in SUS, in five years, would be 555 BRL (345 USD and 600 BRL (372.8 USD million, respectively. The costs from the PET-CT procedure were the most influential parameter in the results. In the most optimistic scenario, the additional budget impact would be reduced to 86.9 BRL (54 USD and 103.8 BRL (64.5 USD million, considering PET-CT for negative CT and PET-CT for all, respectively.CONCLUSIONS The incorporation of PET in the clinical staging of non-small cell lung cancer seems to be financially feasible considering the high budget of the Brazilian Ministry of Health. The potential reduction in the number of unnecessary surgeries may cause the available resources to be more efficiently allocated.

  10. ¹⁸F-fluorodeoxyglucose positron emission tomography-computed tomography for the evaluation of bone metastasis in patients with gastric cancer.

    Science.gov (United States)

    Ma, Dae Won; Kim, Jie-Hyun; Jeon, Tae Joo; Lee, Yong Chan; Yun, Mijin; Youn, Young Hoon; Park, Hyojin; Lee, Sang In

    2013-09-01

    The roles of positron emission tomography and bone scanning in identifying bone metastasis in gastric cancer are unclear. We compared the usefulness of positron emission tomography-computed tomography and scanning in detecting bone metastasis in gastric cancer. Data from 1485 patients diagnosed with gastric cancer who had undergone positron emission tomography-computed tomography and scanning were reviewed. Of 170 enrolled patients who were suspected of bone metastasis in either positron emission tomography or scanning, 81.2% were confirmed to have bone metastasis. The sensitivity, specificity, and accuracy were 93.5%, 25.0%, and 80.6%, respectively, for positron emission tomography and 93.5%, 37.5%, and 82.9%, respectively, for scanning. 87.7% of patients with bone metastasis showed positive findings on two modalities. 15.0% of solitary bone metastases were positive on positron emission tomography only. Positron emission tomography was superior to scanning for the detection of synchronous bone metastasis, but the two modalities were similar for the detection of metachronous bone metastasis. The concordance rate of response assessment after treatment between two modalities was moderate. Positron emission tomography-computed tomography may be more effective for the diagnosis of bone metastasis in the initial staging workup. Conversely, bone scanning and positron emission tomography-computed tomography may be similarly effective for the detection of metachronous bone metastasis. Copyright © 2013 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  11. Post-exercise diastolic stunning detected by velocity vector imaging is a useful marker for induced ischemia in ischemic heart disease.

    Science.gov (United States)

    Kurosawa, Koji; Watanabe, Hiroyuki; Aikawa, Masaru; Mihara, Hirotsugu; Iguchi, Nobuo; Asano, Ryuta; Umemura, Jun; Kurabayashi, Masahiko; Sumiyoshi, Tetsuya

    2013-06-01

    Recently, post-exercise diastolic stunning (PES) has been reported as a new clinical marker of induced ischemia. Velocity vector imaging (VVI) has been developed to visualize regional wall motion abnormalities based on vectors detected by the tissue tracking technique, which has the potential to visualize PES. Thus, the aim of this study was to evaluate the usefulness of PES detection by VVI as an objective marker of ischemia compared to stress thallium-201 (Tl-201) single photon emission computed tomography (SPECT). We studied consecutive patients who were scheduled to undergo exercise stress Tl-201 SPECT for the diagnosis of ischemic heart disease. Transthoracic echocardiography was recorded digitally before and 20 min after exercise for Tl-201 SPECT, and the data were used subsequently for VVI analysis. We defined PES regions as those with new abnormal vectors observed during isovolumic relaxation. After excluding 14 patients with old myocardial infarction and/or atrial fibrillation, echocardiograms suitable for VVI analysis were obtained from 62 of 65 patients (feasibility, 95 %; 44 men; mean age, 64 ± 11 years). SPECT revealed induced ischemia in 20 patients, whereas VVI identified PES in 18 patients. VVI detected inducible ischemia with 85 % sensitivity and 98 % specificity compared to SPECT. VVI detection of PES is a new clinical tool for induced ischemia. Regional diastolic wall motion abnormalities following induced ischemia can be noninvasively detected by VVI.

  12. Computed tomography and (18)F-fluorodeoxyglucose positron emission tomography/computed tomography findings in adrenal candidiasis and histoplasmosis: two cases.

    Science.gov (United States)

    Altinmakas, Emre; Guo, Ming; Kundu, Uma R; Habra, Mouhammed Amir; Ng, Chaan

    2015-01-01

    We report the contrast-enhanced computed tomography (CT) and (18)F-fluorodeoxyglucose positron emission tomography findings in adrenal histoplasmosis and candidiasis. Both demonstrated bilateral hypermetabolic heterogeneous adrenal masses with limited wash-out on delayed CT. Adrenal candidiasis has not been previously reported, nor have the CT wash-out findings in either infection. The adrenal imaging findings are indistinguishable from malignancy, which is more common; but in this setting, physicians should be alert to the differential diagnosis of fungal infections, since it can be equally deadly. Published by Elsevier Inc.

  13. A computable general equilibrium assessment of a developing country joining an Annex B emission permit market

    Energy Technology Data Exchange (ETDEWEB)

    Kemfert, C.; Kremers, H. [Scientific Pool of Environmental Economic Disciplines SPEED, School of Computing Science, Business Administration, Economics and Law, University of Oldenburg, Oldenburg (Germany)

    2003-10-01

    The rejection of the United States to verify the Kyoto Protocol has focussed some attention on the contribution of the developing countries in mitigating the consequences of climate change on the economy. While the USA insisted on an important role for the developing countries, for example by voluntarily accepting an emission target in 2012, the developing countries themselves found their growth hampered by such measures. This paper focusses on the consequences of setting emission targets for developing countries, here China. We consider some proposals for setting such targets. One of these proposals follows the USA by letting China accept its projected 'Business-as-Usual' emission level for 2012 as its target. A proposal by the Center for Clean Air Policy takes more consideration for the viewpoint of the developing countries by imposing a so-called 'growth-baseline' for China, where a target is set on its emission efficiency.

  14. 18 F-fluorodeoxyglucose positron emission tomography-computed tomography for preoperative lymph node staging in patients undergoing radical cystectomy for bladder cancer: a prospective study.

    Science.gov (United States)

    Hitier-Berthault, Maryam; Ansquer, Catherine; Branchereau, Julien; Renaudin, Karine; Bodere, Françoise; Bouchot, Olivier; Rigaud, Jérôme

    2013-08-01

    The objective of our study was to analyze the diagnostic performance of (18) F-fluorodeoxyglucose positron emission tomography-computed tomography for lymph node staging in patients with bladder cancer before radical cystectomy and to compare it with that of computed tomography. A total of 52 patients operated on between 2005 and 2010 were prospectively included in this prospective, mono-institutional, open, non-randomized pilot study. Patients who had received neoadjuvant chemotherapy or radiotherapy were excluded. (18) F-fluorodeoxyglucose positron emission tomography-computed tomography in addition to computed tomography was carried out for lymph node staging of bladder cancer before radical cystectomy. Lymph node dissection during radical cystectomy was carried out. Findings from (18) F-fluorodeoxyglucose positron emission tomography-computed tomography and computed tomography were compared with the results of definitive histological examination of the lymph node dissection. The diagnostic performance of the two imaging modalities was assessed and compared. The mean number of lymph nodes removed during lymph node dissection was 16.5 ± 10.9. Lymph node metastasis was confirmed on histological examination in 22 cases (42.3%). This had been suspected in five cases (9.6%) on computed tomography and in 12 cases (23.1%) on (18) F-fluorodeoxyglucose positron emission tomography-computed tomography. Sensitivity, specificity, positive predictive value, negative predictive value, relative risk and accuracy were 9.1%, 90%, 40%, 57.4%, 0.91 and 55.7%, respectively, for computed tomography, and 36.4%, 86.7%, 66.7%, 65%, 2.72, 65.4%, respectively, for (18) F-fluorodeoxyglucose positron emission tomography-computed tomography. (18) F-fluorodeoxyglucose positron emission tomography-computed tomography is more reliable than computed tomography for preoperative lymph node staging in patients with invasive bladder carcinoma undergoing radical cystectomy. © 2012 The Japanese

  15. Combined computed tomography and fluorodeoxyglucose positron emission tomography in the diagnosis of prosthetic valve endocarditis: a case series.

    Science.gov (United States)

    Bartoletti, Michele; Tumietto, Fabio; Fasulo, Giovanni; Giannella, Maddalena; Cristini, Francesco; Bonfiglioli, Rachele; Raumer, Luigi; Nanni, Cristina; Sanfilippo, Silvia; Di Eusanio, Marco; Scotton, Pier Giorgio; Graziosi, Maddalena; Rapezzi, Claudio; Fanti, Stefano; Viale, Pierluigi

    2014-01-13

    The diagnosis of prosthetic valve endocarditis is challenging. The gold standard for prosthetic valve endocarditis diagnosis is trans-esophageal echocardiography. However, trans-esophageal echocardiography may result in negative findings or yield images difficult to differentiate from thrombus in patients with prosthetic valve endocarditis. Combined computed tomography and fluorodeoxyglucose positron emission tomography is a potentially promising diagnostic tool for several infectious conditions and it has also been employed in patients with prosthetic valve endocarditis but data are still scant. We reviewed the charts of 6 patients with prosthetic aortic valves evaluated for suspicion of prosthetic valve endocarditis, at two different hospital, over a 3-year period. We found 3 patients with early-onset PVE cases and blood cultures yielding Pseudomonas aeruginosa, Staphylococcus epidermidis and Staphylococcus lugdunensis, respectively; and 3 late-onset cases in the remaining 3 patients with isolation in the blood of Streptococcus bovis, Candida albicans and P. aeruginosa, respectively. Initial trans-esophageal echocardiography was negative in all the patients, while fluorodeoxyglucose positron emission tomography showed images suspicious for prosthetic valve endocarditis. In 4 out of 6 patients valve replacement was done with histology confirming the prosthetic valve endocarditis diagnosis. After an adequate course of antibiotic therapy fluorodeoxyglucose positron emission tomography showed resolution of prosthetic valve endocarditis in all the patients. Our experience confirms the potential role of fluoroseoxyglucose positron emission tomography in the diagnosis and follow-up of prosthetic valve endocarditis.

  16. Description and application of the EAP computer program for calculating life-cycle energy use and greenhouse gas emissions of household consumption items

    NARCIS (Netherlands)

    Benders, R.M.J.; Wilting, H.C.; Kramer, K.J.; Moll, H.C.

    2001-01-01

    Focusing on reduction in energy use and greenhouse gas emissions, a life-cycle-based analysis tool has been developed. The energy analysis program (EAP) is a computer program for determining energy use and greenhouse gas emissions related to household consumption items, using a hybrid calculation

  17. Detection of impaired fatty acid metabolism in right ventricular hypertrophy. Assessment by I-123 β-methyl iodophenyl pentadecanoic acid (BMIPP) myocardial single-photon emission computed tomography

    International Nuclear Information System (INIS)

    Kim, Yong-ih; Goto, Hideki; Kobayashi, Katsuhiro; Sawada, Yoshihiro; Miyake, Yoshitaka; Fujiwara, Go; Chiba, Hiroshi; Okada, Tomoya; Nishimura, Tsunehiko.

    1997-01-01

    The subjects consisted of 6 patients with chronic obstructive pulmonary disease, 4 with primary pulmonary hypertension, 2 each with refractory pulmonary tuberculosis, tricuspid insufficiency, pulmonary embolism, 1 each with atrial septal defect, ventricular septal defect (Eisenmenger complex), Ebstein anomaly, and endocardial defect, and 7 healthy controls. SPECT imaging with Tl-201 (Tl) and I-123 BMIPP, and Tc-99m RBC first pass and gated blood pool scintigraphy were performed. Based on Tl planar images, the subjects were classified into 3 groups: 7 patients with no RV visualization (Group A), 11 with moderate RV visualization (Group B) and 9 with marked RV visualization (Group C). As a semi-quantitative evaluation by a myocardial SPECT, 3 regions in 3 representative short axial images were divided into 9 segments, each of which was graded from 0 to +3, and their sum was calculated as the RV score. The right ventricular ejection fraction (RVEF and the left ventricular ejection fraction were obtained by Tc-99m RBC cardiac scintigraphy. The groups with marked visualization of the right ventricle had lower RVEF, and there was a good correlation between the RVEF and the RV score with both a and BMIPP. Although a good correlation was demonstrated between the RV score with Tl and BMIPP in Groups A and B, in Group C, in which there was marked RV Tl visualization, the RV score with BMIPP was significantly smaller than with Tl. These findings suggest that impaired fatty acid metabolism may exist in severely hypertrophic right ventricle due to RV overload. (K.H.)

  18. A method for calculating regional cerebral blood flow from emission computed tomography of inert gas concentrations

    DEFF Research Database (Denmark)

    Celsis, P; Goldman, T; Henriksen, L

    1981-01-01

    Emission tomography of positron or gamma emitting inert gases allows calculation of regional cerebral blood flow (rCBF) in cross-sectional slices of human brain. An algorithm is presented for rCBF calculations from a sequence of time averaged tomograms using inhaled 133Xe. The approach is designed...... of four 1 min pictures and using a fixed value for the brain:blood partition coefficient, lambda. The method is essentially based on the bolus distribution principle, and it allows the estimation of blood flow in ischemic areas. Application to positron emission tomography is discussed....

  19. Use of computed tomography and positron emission tomography/computed tomography for staging of local extent in patients with malignant pleural mesothelioma.

    Science.gov (United States)

    Frauenfelder, Thomas; Kestenholz, Peter; Hunziker, Roger; Nguyen, Thi Dan Linh; Fries, Martina; Veit-Haibach, Patrick; Husmann, Lars; Stahel, Rolf; Weder, Walter; Opitz, Isabelle

    2015-01-01

    The objective of this study was to determine the diagnostic value of computed tomography (CT) and positron emission tomography (PET)/CT for staging of malignant pleural mesothelioma (MPM) in patients undergoing induction chemotherapy. Sixty-two patients (median age, 61 years; female: n = 9) with proven MPM underwent CT after induction chemotherapy. Of these, 28 underwent additional PET/CT. Extrapleural pneumonectomy was performed for pathological TNM staging. Clinical TNM stage was assessed by 3 independent readers. Relative and absolute underestimation and overestimation were compared with pathological tumor stage. Sensitivity, specificity, and accuracy for differentiation between stages T2 and T3 were assessed. Interobserver agreement between the readers was analyzed (κ). Positron emission tomography/CT and CT underestimated T stage in up to 30% of the cases. Positron emission tomography/CT had a higher accuracy for tumor extent compared with CT (PET/CT: 0.92; CT: 0.84). The accuracy for nodal staging was higher for CT than for PET/CT (PET/CT: 0.78; CT: 0.87). Concerning International Mesothelioma Interest Group classification, PET/CT improved the accuracy of preoperative staging compared with CT (PET/CT: 0.91; CT: 0.82). Interobserver agreement was moderate for CT (0.48-0.62) and good for PET/CT (0.64-0.83) for T staging. For nodal staging, interobserver agreement was fair to moderate for CT and good for PET/CT (CT: 0.37-0.51; PET/CT: 0.73-0.76). Positron emission tomography/CT is more accurate and has a lower interobserver variability for clinical intrathoracic staging of MPM compared with CT. Nevertheless PET/CT underestimated tumor stage in a substantial number of cases, showing the need for a more accurate imaging technology or approach.

  20. Evaluative studies in nuclear medicine research. Emission-computed tomography assessment. Progress report 1 January-15 August 1981

    International Nuclear Information System (INIS)

    Potchen, E.J.

    1981-01-01

    Questions regarding what imaging performance goals need to be met to produce effective biomedical research using positron emission computer tomography, how near those performance goals are to being realized by imaging systems, and the dependence of currently-unachieved performance goals on design and operational factors have been addressed in the past year, along with refinement of economic estimates for the capital and operating costs of a PECT research facility. The two primary sources of information have been solicitations of expert opinion and review of current literature

  1. Effect of expression of P-glycoprotein on technetium-99m methoxyisobutylisonitrile single photon emission computed tomography of brain tumors

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, Yasushi; Matsumura, Akira; Nose, Tadao [Tsukuba Univ., Ibaraki (Japan). Inst. of Clinical Medicine

    2002-08-01

    The expression of P-glycoprotein was investigated imunohistochemically in 26 brain tumor tissues and compared with the findings of technetium-99m methoxyisobutylisonitrile single photon emission computed tomography ({sup 99m}Tc-MIBI SPECT) to clarify the effect of P-glycoprotein on the diagnostic accuracy. P-glycoprotein labeling index of both tumor cells and vascular endothelial cells showed no clear relationship with the findings of {sup 99m}Tc-MIBI SPECT imaging. Expression of P-glycoprotein has no effect on the diagnostic accuracy of {sup 99m}Tc-MIBI SPECT. (author)

  2. Positron emission tomography/computed tomography and biomarkers for early treatment response evaluation in metastatic colon cancer

    DEFF Research Database (Denmark)

    Engelmann, Bodil E.; Loft, Annika; Kjær, Andreas

    2014-01-01

    BACKGROUND: Treatment options for metastatic colon cancer (mCC) are widening. We prospectively evaluated serial 2-deoxy-2-[18F]fluoro-d-glucose positron-emission tomography/computed tomography (PET/CT) and measurements of tissue inhibitor of metalloproteinases-1 (TIMP-1), carcinoembryonic antigen...... evaluated by PET/CT before treatment, after one and four treatment series. Morphological and metabolic response was independently assessed according to Response Evaluation Criteria in Solid Tumors and European Organization for Research and Treatment of Cancer PET criteria. Plasma TIMP-1, plasma u...

  3. Spectrum of fluorodeoxyglucose-positron emission tomography/computed tomography and magnetic resonance imaging findings of ovarian tumors.

    Science.gov (United States)

    Kitajima, Kazuhiro; Ueno, Yoshiko; Maeda, Tetsuo; Murakami, Koji; Kaji, Yasushi; Kita, Masato; Suzuki, Kayo; Sugimura, Kazuro

    2011-11-01

    The purpose of this article is to review fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) and magnetic resonance imaging (MRI) findings in a variety of benign, malignant, and borderline malignant ovarian tumors. It is advantageous to become familiar with the wide variety of FDG-PET/CT findings of this entity. Benign ovarian tumors generally have faint uptake, whereas endometriomas, fibromas, and teratomas show mild to moderate uptake. Malignant ovarian tumors generally have intense uptake, whereas tumors with a small solid component often show minimal uptake.

  4. Modeling and Computation of Transboundary Industrial Pollution with Emission Permits Trading by Stochastic Differential Game.

    Directory of Open Access Journals (Sweden)

    Shuhua Chang

    Full Text Available Transboundary industrial pollution requires international actions to control its formation and effects. In this paper, we present a stochastic differential game to model the transboundary industrial pollution problems with emission permits trading. More generally, the process of emission permits price is assumed to be stochastic and to follow a geometric Brownian motion (GBM. We make use of stochastic optimal control theory to derive the system of Hamilton-Jacobi-Bellman (HJB equations satisfied by the value functions for the cooperative and the noncooperative games, respectively, and then propose a so-called fitted finite volume method to solve it. The efficiency and the usefulness of this method are illustrated by the numerical experiments. The two regions' cooperative and noncooperative optimal emission paths, which maximize the regions' discounted streams of the net revenues, together with the value functions, are obtained. Additionally, we can also obtain the threshold conditions for the two regions to decide whether they cooperate or not in different cases. The effects of parameters in the established model on the results have been also examined. All the results demonstrate that the stochastic emission permits prices can motivate the players to make more flexible strategic decisions in the games.

  5. PABS: A Computer Program to Normalize Emission Probabilities and Calculate Realistic Uncertainties

    International Nuclear Information System (INIS)

    Caron, D.S.; Browne, E.; Norman, E.B.

    2009-01-01

    The program PABS normalizes relative particle emission probabilities to an absolute scale and calculates the relevant uncertainties on this scale. The program is written in Java using the JDK 1.6 library. For additional information about system requirements, the code itself, and compiling from source, see the README file distributed with this program. The mathematical procedures used are given.

  6. Biomass Burning Emissions in the Cerrado of Brazil Computed with Remote Sensing Data and GIS

    Science.gov (United States)

    Guild, Liane S.; Brass, James A.; Chatfield, Robert B.; Hlavka, Christine A.; Riggan, Philip J.; Setzer, Alberto; Pereira, Joao A. Raposo; Peterson, David L. (Technical Monitor)

    1994-01-01

    Biomass burnin is a common force in much of the developing tropical world where it has wide-ranging environmental impacts. Fire is a component of tropical deforestation and is 0 p often used to clear broad expanses of land for shifting agriculture and cattle ranching. Frequent burning in the tropical savannas is a distinct problem from that of primary forest. In Brazil, most of the burning occurs in the cerrado which occupies approximately 1,800,000 km2, primarily on the great plateau in central Brazil. Wildland and agricultural fires are dramatic sources of regional air pollution in central Brazil. Biomass burning is an important source of a large number of trace gases including greenhouse gases and other chemically active species. Knowledge of trace gas emissions from biomass burning in Brazil is limited by a number of factors, most notably relative emission factors for gases from specific fire types/fuels and accurate estimates of temporal and spatial distribution and extent of fire activity. Estimates of trace gas emissions during September 1992 will be presented that incorporates a digital map of vegetation classes, pyrogenic emission factors calculated from ground and aircraft missions, and Instituto Nacional de Pesquisas Espaciais (INPE) fire products derived from Advanced Very High Resolution Radiometer (AVHRR) data. The regional emissions calculated from National Oceanographic and Atmospheric Administration (NOAA) AVHRR estimates of fire activity will provide an independent estimate for comparison with results obtained by the National Aeronautics and Space Administration (NASA) Transport and Atmospheric Chemistry Near the Equator - Atlantic (TRACE-A) experiments.

  7. Data on analysis of coronary atherosclerosis on computed tomography and 18F-sodium fluoride positron emission tomography

    Directory of Open Access Journals (Sweden)

    Toshiro Kitagawa

    2017-08-01

    Full Text Available This article contains the data showing illustrative examples of plaque classification on coronary computed tomography angiography (CCTA and measurement of 18F-sodium fluoride (18F-NaF uptake in coronary atherosclerotic lesions on positron emission tomography (PET. We divided the lesions into one of three plaque types on CCTA (calcified plaque, non-calcified plaque, partially calcified plaque. Focal 18F-NaF uptake of each lesion was quantified using maximum tissue-to-background ratio. This article also provides a representative case with a non-calcified coronary plaque detected on CCTA and identified on 18F-NaF PET/non-contrast computed tomography based on a location of a vessel branch as a landmark. These complement the data reported by Kitagawa et al. (2017 [1].

  8. Contrast-enhanced fluorodeoxyglucose positron emission tomography/contrast-enhanced computed tomography in mediastinal T-cell lymphoma with superior vena cava syndrome

    International Nuclear Information System (INIS)

    Santhosh, Sampath; Gorla, Arun Kumar Reddy; Bhattacharya, Anish; Varma, Subhash Chander; Mittal, Bhagwant Rai

    2016-01-01

    Positron emission tomography-computed tomography (PET/CT) is a routine investigation for the staging of lymphomas. Contrast-enhanced computed tomography is mandatory whenever parenchymal lesions, especially in the liver and spleen are suspected. We report a rare case of primary mediastinal T-cell lymphoma evaluated with contrast-enhanced PET/CT that showed features of superior vena cava syndrome

  9. Lung Cancer in Patients With Tuberculous Fibrothorax and Empyema: Computed Tomography and 18F-Fluorodeoxyglucose Positron Emission Tomography Findings.

    Science.gov (United States)

    Xu, Hai; Koo, Hyun Jung; Lee, Han Na; Lim, Soyeoun; Lee, Jae Wook; Choi, Chang-Min; Kim, Mi Young

    The aim of this study was to describe the characteristics of lung cancers in patients with tuberculous fibrothorax or empyema. We retrospectively evaluated 138 consecutive patients with a diagnosis of lung cancer combined with fibrothorax (n = 127) or empyema (n = 11) from January 2005 to May 2015. All patients underwent computed tomography, and 105 underwent F-fluorodeoxyglucose positron emission tomography. Clinical, pathologic, and computed tomography characteristics and maximum standardized uptake values on positron emission tomography of 76 cancers ipsilateral to the fibrothorax or empyema (group 1) were compared with those of 62 contralateral cancers (group 2). The median age at diagnosis of patients was 70 years, with a male-to-female ratio of 8.9:1. The most common type was squamous cell carcinoma (41.3%) followed by adenocarcinoma (39.1%). Most were in the peripheral lung (70.3%), and half abutted the pleura. The median maximum standardized uptake value was 8.9. Tumors in group 1 were larger (median, 48.5 vs 42.8 mm, P = 0.036) and more advanced (T3 or T4) (P = 0.014) than those in group 2. Lung cancers ipsilateral to tuberculous fibrothorax or empyema presented larger and advanced T stages, and the diagnosis could be delayed. The most common type cancer was squamous cell carcinoma.

  10. Estimation of right ventricular pressure in children by thallium-201 myocardial imaging using single-photon emission computed tomography.

    Science.gov (United States)

    Akiba, T; Yoshikawa, M; Otaki, S; Nakasato, M; Suzuki, H; Sato, S; Sato, T

    1992-03-01

    Thallium-201 myocardial imaging using single-photon emission computed tomography was performed to estimate right ventricular (RV) systolic pressure in 34 children (aged 4.1 to 16.1 years, mean 7.9 +/- 2.9). Acquisition of the images was performed using a semicircular arc of 180 degrees. On a short-axis slice, a line drawn perpendicular to the ventricular septum so as to cross the RV free wall showing maximum uptake was defined as the region of interest. Thallium-201 counts in regions of interest over both RV and left ventricular (LV) free walls were measured. The ratio of RV-to-LV peak thallium-201 counts was compared with RV peak systolic pressure and the ratio of RV-to-LV peak systolic pressure measured at cardiac catheterization. Both RV peak systolic pressure and the ratio of RV-to-LV peak systolic pressure correlated well with the ratio of RV-to-LV peak thallium-201 counts (r = 0.95 and 0.96, respectively). The ratio of RV-to-LV peak thallium-201 counts greater than or equal to 0.45 could predict RV pressure overloading with a sensitivity of 92%, and a specificity of 88%. Thus, the quantitative analysis of thallium-201 myocardial imaging using single-photon emission computed tomography permits the noninvasive and accurate estimation of RV systolic pressure in children.

  11. Clinical value of whole body fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography in the detection of metastatic bladder cancer.

    Science.gov (United States)

    Yang, Zhongyi; Pan, Lingling; Cheng, Jingyi; Hu, Silong; Xu, Junyan; Ye, Dingwei; Zhang, Yingjian

    2012-07-01

    To investigate the value of whole-body fluorine-18 2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography for the detection of metastatic bladder cancer. From December 2006 to August 2010, 60 bladder cancer patients (median age 60.5 years old, range 32-96) underwent whole body positron emission tomography/computed tomography positron emission tomography/computed tomography. The diagnostic accuracy was assessed by performing both organ-based and patient-based analyses. Identified lesions were further studied by biopsy or clinically followed for at least 6 months. One hundred and thirty-four suspicious lesions were identified. Among them, 4 primary cancers (2 pancreatic cancers, 1 colonic and 1 nasopharyngeal cancer) were incidentally detected, and the patients could be treated on time. For the remaining 130 lesions, positron emission tomography/computed tomography detected 118 true positive lesions (sensitivity = 95.9%). On the patient-based analysis, the overall sensitivity and specificity resulted to be 87.1% and 89.7%, respectively. There was no difference of sensitivity and specificity in patients with or without adjuvant treatment in terms of detection of metastatic sites by positron emission tomography/computed tomography. Compared with conventional imaging modality, positron emission tomography/computed tomography correctly changed the management in 15 patients (25.0%). Positron emission tomography/computed tomography has excellent sensitivity and specificity in the detection of metastatic bladder cancer and it provides additional diagnostic information compared to standard imaging techniques. © 2012 The Japanese Urological Association.

  12. Clinical value of whole body fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography in the detection of metastatic bladder cancer

    International Nuclear Information System (INIS)

    Yang Zhongyi; Pan Lingling; Cheng Jingyi; Hu Silong; Xu Junyan; Zhang Yingjian; Ye Dingwei

    2012-01-01

    The objective of this study was to investigate the value of whole-body fluorine-18 2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography for the detection of metastatic bladder cancer. From December 2006 to August 2010, 60 bladder cancer patients (median age 60.5 years old, range 32-96) underwent whole body positron emission tomography/computed tomography positron emission tomography/computed tomography. The diagnostic accuracy was assessed by performing both organ-based and patient-based analyses. Identified lesions were further studied by biopsy or clinically followed for at least 6 months. One hundred and thirty-four suspicious lesions were identified. Among them, 4 primary cancers (2 pancreatic cancers, 1 colonic and 1 nasopharyngeal cancer) were incidentally detected, and the patients could be treated on time. For the remaining 130 lesions, positron emission tomography/computed tomography detected 118 true positive lesions (sensitivity=95.9%). On the patient-based analysis, the overall sensitivity and specificity resulted to be 87.1% and 89.7%, respectively. There was no difference of sensitivity and specificity in patients with or without adjuvant treatment in terms of detection of metastatic sites by positron emission tomography/computed tomography. Compared with conventional imaging modality, positron emission tomography/computed tomography correctly changed the management in 15 patients (25.0%). Positron emission tomography/computed tomography has excellent sensitivity and specificity in the detection of metastatic bladder cancer and it provides additional diagnostic information compared to standard imaging techniques. (author)

  13. Position emission tomography with or without computed tomography in the primary staging of Hodgkin's lymphoma

    DEFF Research Database (Denmark)

    Hutchings, Martin; Loft, Annika; Hansen, Mads

    2006-01-01

    BACKGROUND AND OBJECTIVES: In order to receive the most appropriate therapy, patients with Hodgkin's lymphoma (HL) must be accurately stratified into different prognostic staging groups. Computed tomography (CT) plays a pivotal role in the conventional staging. The aim of the present study...

  14. Development of a technique for three-dimensional image reconstruction from emission computed tomograms (ECT)

    International Nuclear Information System (INIS)

    Gerischer, R.

    1987-01-01

    The described technique for three-dimensional image reconstruction from ECT sections is based on a simple procedure, which can be carried out with the aid of any standard-type computer used in nuclear medicine and requires no sophisticated arithmetic approach. (TRV) [de

  15. Modelling and computing the peaks of carbon emission with balanced growth

    International Nuclear Information System (INIS)

    Chang, Shuhua; Wang, Xinyu; Wang, Zheng

    2016-01-01

    Highlights: • We use a more practical utility function to quantify the society’s welfare. • A so-called discontinuous Galerkin method is proposed to solve the ordinary differential equation satisfied by the consumption. • The theoretical results of the discontinuous Galerkin method are obtained. • We establish a Markov model to forecast the energy mix and the industrial structure. - Abstract: In this paper, we assume that under the balanced and optimal economic growth path, the economic growth rate is equal to the consumption growth rate, from which we can obtain the ordinary differential equation governing the consumption level by solving an optimal control problem. Then, a novel numerical method, namely a so-called discontinuous Galerkin method, is applied to solve the ordinary differential equation. The error estimation and the superconvergence estimation of this method are also performed. The model’s mechanism, which makes our assumption coherent, is that once the energy intensity is given, the economic growth is determined, followed by the GDP, the energy demand and the emissions. By applying this model to China, we obtain the conclusion that under the balanced and optimal economic growth path the CO 2 emission will reach its peak in 2030 in China, which is consistent with the U.S.-China Joint Announcement on Climate Change and with other previous scientific results.

  16. Computation and measurement of a plasma temperature using the emission lines of copper

    International Nuclear Information System (INIS)

    Sassi, M.; Pierre, L.; Benard, J.; Cahen, C.

    1994-01-01

    The use of copper emission lines for temperature measurement in plasma environments is presented. The article features the problems encountered with such a measurement method when used in a stationary and a non-stationary plasma. In the first case, we were concerned with the temperature measurements in the jet of a 2 MW industrial plasma torche. The plasma was stationary and the measurement geometry allowed the use of the Abel inversion method to recover the temperature profiles in the plasma jet. The limitations of the measurement method on the jet boundaries as well as the cooling of the plasma by entrainement of cold air are discussed. In the second case, a non-stationary plasma in a 1.4 MW electric furnace was studied. This study allowed to feature the role of the detector dynamics as related to the dynamics of the observed medium. The obtained measurements show only a probable temperature in the immediate proximity of the arc. Finally, we conclude on the validity of copper as a tracer and the use of spontaneous emission spectroscopy, and easy method to implement, compared to other sophisticated temperature measurement methods. (orig.)

  17. Os Trigonum – Sheer Incidental or Quite Significant? Single Photon Emission Computed Tomography/Computed Tomography's Role in a Case of Ankle Impingement

    International Nuclear Information System (INIS)

    Chokkappan, Kabilan; Srinivasan, Sivasubramanian; Subramanian, Manickam; Kannivelu, Anbalagan

    2015-01-01

    Accessory ossicles are widely prevalent in the ankle and foot. Although they are often asymptomatic, they can present clinically with symptoms at times. When they occur bilaterally in a patient who presents with unilateral complaints, it is clinically difficult to attribute the symptoms to the presence of these common anatomic variants. One needs specific imaging to assess the clinical relevance of the accessory ossicles, in order to tailor the treatment plan. The case presented in this article is one such example, where the patient presented with chronic unilateral ankle pain and initial radiographs revealed bilateral os trigonum and os subtibiale. He underwent a technetium-99m methyl diphosphonate (Tc-99m MDP) bone scan and single photon emission computed tomography/computed tomography (SPECT/CT). The Tc-99m MDP scan showed a focal uptake in the ankle of concern. SPECT/CT complemented the finding by exactly localizing the uptake to the posterior subtalar joint and around the os trigonum, thereby pointing to the diagnosis of os trigonum syndrome

  18. The use of filtering methods to compensate for constant attenuation in single-photon emission computed tomography

    International Nuclear Information System (INIS)

    Gullberg, G.T.; Budinger, T.F.

    1981-01-01

    A back projection of filtered projection (BKFIL) reconstruction algorithm is presented that is applicable to single-photon emission computed tomography (ECT) in the presence of a constant attenuating medium such as the brain. The filters used in transmission computed tomography (TCT)-comprised of a ramp multiplied by window functions-are modified so that the single-photon ECT filter is a function of the constant attenuation coefficient. The filters give good reconstruction results with sufficient angular and lateral sampling. With continuous samples the BKFIL algorithm has a point spread function that is the Hankel transform of the window function. The resolution and statistical properties of the filters are demonstrated by various simulations which assume an ideal detector response. Statistical formulas for the reconstructed image show that the square of the percent-root-mean-square (percent-rms) uncertainty of the reconstruction is inversely proportional to the total measured counts. The results indicate that constant attenuation can be compensated for by using an attenuation-dependent filter that reconstructs the transverse section reliably. Computer time requirements are two times that of conventional TCT or positron ECT and there is no increase in memory requirements

  19. Routine positron emission tomography and positron emission tomography/computed tomography in melanoma staging with positive sentinel node biopsy is of limited benefit.

    Science.gov (United States)

    Constantinidou, Anastasia; Hofman, Michael; O'Doherty, Michael; Acland, Katharine M; Healy, Ciaran; Harries, Mark

    2008-02-01

    Positron emission tomography (PET) is increasingly used for the staging and management of melanoma. The aim of this study was to evaluate the role of PET or PET/ computed tomography (CT) as a routine procedure in patients with positive sentinel node biopsy (SNB). Thirty patients with melanoma of Breslow thickness greater than 1 mm who had PET or PET/CT scans performed within 100 days after a positive SNB were reviewed retrospectively. Two patients (6%) had a positive PET scan, none of which were melanoma related. The first patient had a synchronous neuroendocrine thyroid tumour and the second patient had increased uptake in the chest wall, which proved to be old trauma. Lymph node dissection was positive in five cases (16%). With a median follow-up of 24 months, 21 patients remained disease free. In none of the 30 cases did the early PET scan after a positive SNB alter subsequent melanoma management. The role of PET scanning soon after a positive sentinel node biopsy seems to be of limited benefit. It is questionable whether any imaging is beneficial at this stage. The results of this review suggest that PET scanning might not be indicated for this group of patients.

  20. A case of skeletal tuberculosis and psoas abscess: disease activity evaluated using (18) F-fluorodeoxyglucose positron emission tomography-computed tomography.

    Science.gov (United States)

    Kimizuka, Yoshifumi; Ishii, Makoto; Murakami, Koji; Ishioka, Kota; Yagi, Kazuma; Ishii, Ken; Watanabe, Kota; Soejima, Kenzo; Betsuyaku, Tomoko; Hasegawa, Naoki

    2013-11-14

    Psoas abscess complicating tuberculous spondylitis is a rare morbidity in extrapulmonary tuberculosis. There are no established guidelines for evaluating the clinical response of psoas abscess. Although several studies have shown that positron emission tomography-computed tomography with 18 F-fluorodeoxyglucose can play a potential role in diagnosing multifocal tuberculosis and monitoring the clinical response of pulmonary tuberculosis, to our knowledge, this is the first report demonstrating that positron emission tomography-computed tomography is useful for evaluating local inflammation and disease activity of a tuberculous psoas abscess. We report a case of multifocal bone and lymph node tuberculosis with concomitant lumbar psoas abscess in a 77-year-old man, along with a literature review. An initial positron emission tomography-computed tomography scan showed intense 18 F-fluorodeoxyglucose accumulation in the sternum, ribs, vertebrae, and lymph nodes. The patient was successfully treated with antitubercular agents and computed tomography-guided drainage therapy. A follow-up positron emission tomography-computed tomography after abscess drainage and 9 months of antitubercular drug treatment revealed that the majority of lesions improved; however, protracted inflammation surrounding the psoas abscess was still observed. These results indicate that disease activity of psoas abscess can remain, even after successful drainage and antitubercular medication regime of appropriate duration. We have successfully followed up the extent of skeletal tuberculosis complicated with psoas abscess by positron emission tomography-computed tomography. In this patient, positron emission tomography-computed tomography is useful for evaluating the disease activity of tuberculous psoas abscess and for assessing the appropriate duration of antitubercular drug therapy in psoas abscess.

  1. A case of skeletal tuberculosis and psoas abscess: disease activity evaluated using 18 F-fluorodeoxyglucose positron emission tomography-computed tomography

    International Nuclear Information System (INIS)

    Kimizuka, Yoshifumi; Hasegawa, Naoki; Ishii, Makoto; Murakami, Koji; Ishioka, Kota; Yagi, Kazuma; Ishii, Ken; Watanabe, Kota; Soejima, Kenzo; Betsuyaku, Tomoko

    2013-01-01

    Psoas abscess complicating tuberculous spondylitis is a rare morbidity in extrapulmonary tuberculosis. There are no established guidelines for evaluating the clinical response of psoas abscess. Although several studies have shown that positron emission tomography-computed tomography with 18 F-fluorodeoxyglucose can play a potential role in diagnosing multifocal tuberculosis and monitoring the clinical response of pulmonary tuberculosis, to our knowledge, this is the first report demonstrating that positron emission tomography-computed tomography is useful for evaluating local inflammation and disease activity of a tuberculous psoas abscess. We report a case of multifocal bone and lymph node tuberculosis with concomitant lumbar psoas abscess in a 77-year-old man, along with a literature review. An initial positron emission tomography-computed tomography scan showed intense 18 F-fluorodeoxyglucose accumulation in the sternum, ribs, vertebrae, and lymph nodes. The patient was successfully treated with antitubercular agents and computed tomography-guided drainage therapy. A follow-up positron emission tomography-computed tomography after abscess drainage and 9 months of antitubercular drug treatment revealed that the majority of lesions improved; however, protracted inflammation surrounding the psoas abscess was still observed. These results indicate that disease activity of psoas abscess can remain, even after successful drainage and antitubercular medication regime of appropriate duration. We have successfully followed up the extent of skeletal tuberculosis complicated with psoas abscess by positron emission tomography-computed tomography. In this patient, positron emission tomography-computed tomography is useful for evaluating the disease activity of tuberculous psoas abscess and for assessing the appropriate duration of antitubercular drug therapy in psoas abscess

  2. Improving the quantitative accuracy of optical-emission computed tomography by incorporating an attenuation correction: application to HIF1 imaging

    Science.gov (United States)

    Kim, E.; Bowsher, J.; Thomas, A. S.; Sakhalkar, H.; Dewhirst, M.; Oldham, M.

    2008-10-01

    Optical computed tomography (optical-CT) and optical-emission computed tomography (optical-ECT) are new techniques for imaging the 3D structure and function (including gene expression) of whole unsectioned tissue samples. This work presents a method of improving the quantitative accuracy of optical-ECT by correcting for the 'self'-attenuation of photons emitted within the sample. The correction is analogous to a method commonly applied in single-photon-emission computed tomography reconstruction. The performance of the correction method was investigated by application to a transparent cylindrical gelatin phantom, containing a known distribution of attenuation (a central ink-doped gelatine core) and a known distribution of fluorescing fibres. Attenuation corrected and uncorrected optical-ECT images were reconstructed on the phantom to enable an evaluation of the effectiveness of the correction. Significant attenuation artefacts were observed in the uncorrected images where the central fibre appeared ~24% less intense due to greater attenuation from the surrounding ink-doped gelatin. This artefact was almost completely removed in the attenuation-corrected image, where the central fibre was within ~4% of the others. The successful phantom test enabled application of attenuation correction to optical-ECT images of an unsectioned human breast xenograft tumour grown subcutaneously on the hind leg of a nude mouse. This tumour cell line had been genetically labelled (pre-implantation) with fluorescent reporter genes such that all viable tumour cells expressed constitutive red fluorescent protein and hypoxia-inducible factor 1 transcription-produced green fluorescent protein. In addition to the fluorescent reporter labelling of gene expression, the tumour microvasculature was labelled by a light-absorbing vasculature contrast agent delivered in vivo by tail-vein injection. Optical-CT transmission images yielded high-resolution 3D images of the absorbing contrast agent, and

  3. Computational fluid dynamics (CFD) simulation of CO2 emission from a thermal power plant in an urban environment.

    Science.gov (United States)

    Toja-Silva, Francisco; Chen, Jia; Hachinger, Stephan

    2017-04-01

    Climate change, a societal challenge for the European Union, is affecting all regions in Europe and has a profound impact on society and environment. It is now clear that the present global warming period is due to the strong anthropogenic greenhouse gas (GHG) emission, occurring at an unprecedented rate. Therefore, the identification and control of the greenhouse gas sources has a great relevance. Since the GHG emissions from cities are the largest human contribution to climate change, the present investigation focuses on the urban environment. Bottom-up annual emission inventories are compiled for most countries. However, a rigorous approach requires to perform experimental measurements in order to verify the official estimates. Measurements of column-averaged dry-air mole fractions of GHG (XGHG) can be used for this. To comprehensively detect and quantify GHG emission sources, these punctual column data, however, have to be extended to the surrounding urban map, requiring a deep understanding of the gas transport. The resulting emission estimation will serve several practical purposes, e.g. the verification of official emission rates and the determination of trends in urban emissions. They will enable the administration to make targeted and economically efficient decisions about mitigation options, and help to stop unintentional and furtive releases. With this aim, this investigation presents a completely new approach to the analysis of the carbon dioxide (CO2) emissions from fossil fuel thermal power plants in urban environments by combining differential column measurements with computational fluid dynamics (CFD) simulations in order to deeply understand the experimental conditions. The case study is a natural gas-fueled cogeneration (combined heat and power, CHP) thermal power plant inside the city of Munich (Germany). The software used for the simulations (OpenFOAM) was modified in order to use the most advanced RANS turbulence modeling (i.e. Durbin) and

  4. Three-dimensional single-photon emission computed tomography using cone beam collimation (CB-SPECT)

    International Nuclear Information System (INIS)

    Jaszczak, R.J.; Floyd, C.E. Jr.; Manglos, S.H.; Greer, K.L.; Coleman, R.E.

    1986-01-01

    A simple and economically practical method of improving the sensitivity of camera-based SPECT was developed using converging (cone-beam) collimation. This geometry is particularly advantageous for SPECT devices using large field-of-view cameras in imaging smaller, centrally located activity distributions. Geometric sensitivities, spatial resolutions, and fields-of-view of a cone-beam collimator having a focal length of 48 cm and a similarly designed parallel hole collimator were compared analytically. At 15 cm from the collimator surface the point-source sensitivity of the cone-beam collimator was 2.4 times the sensitivity of the parallel-hole collimator. SPECT projection data (simulated using Monte Carlo methodology) were reconstructed using a 3-D filtered backprojection algorithm. Cone-beam emission CT (CB-SPECT) seems potentially useful for animal investigations, pediatric studies, and for brain imaging

  5. ACR-SPR-STR Practice Parameter for the Performance of Cardiac Positron Emission Tomography - Computed Tomography (PET/CT) Imaging.

    Science.gov (United States)

    Subramaniam, Rathan M; Janowitz, Warren R; Johnson, Geoffrey B; Lodge, Martin A; Parisi, Marguerite T; Ferguson, Mark R; Hellinger, Jeffrey C; Gladish, Gregory W; Gupta, Narainder K

    2017-12-01

    This clinical practice parameter has been developed collaboratively by the American College of Radiology (ACR), the Society for Pediatric Radiology (SPR), and the Society of Thoracic Radiology (STR). This document is intended to act as a guide for physicians performing and interpreting positron emission tomography-computed tomography (PET/CT) of cardiac diseases in adults and children. The primary value of cardiac PET/CT imaging include evaluation of perfusion, function, viability, inflammation, anatomy, and risk stratification for cardiac-related events such as myocardial infarction and death. Optimum utility of cardiac PET/CT is achieved when images are interpreted in conjunction with clinical information and laboratory data. Measurement of myocardial blood flow, coronary flow reserve and detection of balanced ischemia are significant advantages of cardiac PET perfusion studies. Increasingly cardiac PET/CT is used in diagnosis and treatment response assessment for cardiac sarcoidosis.

  6. Cerebral perfusion inhomogeneities in schizophrenia demonstrated with single photon emission computed tomography and Tc99m-hexamethylpropyleneamineoxim

    International Nuclear Information System (INIS)

    Bajc, M.; Basic, M.; Topuzovic, N.; Babic, C.; Medved, V.

    1989-01-01

    Cerebral blood flow was measured in relative terms with Tc99m-hexamethylpropyleneamineoxim (HMPAO) and single photon emission computed tomography (SPECT) in 28 female schizophrenic patients (20 acute and 8 chronic) classified according to DSM-III. Eleven normals served as controls. The acute patients were classified according to positive and negative symptoms. Patients with predominantly positive symptoms showed by and large normal and homogeneous cerebral isotope uptake. Those with negative symptoms, and the chronic patients, showed inhomogeneous tracer uptake with multiple regions of hypoperfusion in slices 4-6 cm above the orbitomeatal line. The findings support in principle the notion that schizophrenia with negative or chronic symptoms does not affect the whole brain homogeneously. Brain imaging with Tc99m-HMPAO and SPECT might be used to distinguish various types of schizophrenia. (author)

  7. Benign thyroid and neck lesions mimicking malignancy with false positive findings on positron emission tomography-computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Ye Ri; Kim, Shin Young; Lee, Sang Mi [Soonchunhyang University Cheonan Hospital, Cheonan (Korea, Republic of); Lee, Deuk Young [Dept. of Surgery, Younsei Angelot Women' s Clinic, Cheonan (Korea, Republic of)

    2017-02-15

    The increasing use of positron emission tomography-computed tomography (PET/CT) has led to the frequent detection of incidental thyroid and neck lesions with increased 18F-deoxyglucose (FDG) uptake. Although lesions with increased FDG uptake are commonly assumed to be malignant, benign lesions may also exhibit increased uptake. The purpose of this pictorial essay is to demonstrate that benign thyroid and neck lesions can produce false-positive findings on PET/CT, and to identify various difficulties in interpretation. It is crucial to be aware that differentiating between benign and malignant lesions is difficult in a considerable proportion of cases, when relying only on PET/CT findings. Correlation of PET/CT findings with additional imaging modalities is essential to avoid misdiagnosis.

  8. [18F]Fluorodeoxyglucose (FDG)-Positron Emission Tomography (PET)/Computed Tomography (CT) in Suspected Recurrent Breast Cancer

    DEFF Research Database (Denmark)

    Hildebrandt, Malene Grubbe; Gerke, Oke; Baun, Christina

    2016-01-01

    PURPOSE: To prospectively investigate the diagnostic accuracy of [(18)F]fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) with dual-time-point imaging, contrast-enhanced CT (ceCT), and bone scintigraphy (BS) in patients with suspected breast cancer recurrence....... PATIENTS AND METHODS: One hundred women with suspected recurrence of breast cancer underwent 1-hour and 3-hour FDG-PET/CT, ceCT, and BS within approximately 10 days. The study was powered to estimate the precision of the individual imaging tests. Images were visually interpreted using a four......-point assessment scale, and readers were blinded to other test results. The reference standard was biopsy along with treatment decisions and clinical follow-up (median, 17 months). RESULTS: FDG-PET/CT resulted in no false negatives and fewer false positives than the other imaging techniques. Accuracy of results...

  9. Usefulness of acute myocardial infarct size and localization using Tc-99m-pyrophosphate and single photon emission computed tomography

    International Nuclear Information System (INIS)

    Fujisue, Ryu; Ohyanagi, Mitsumasa; Todo, Yasuhiro

    1985-01-01

    Tc-99m-Pyrophosphate(PYP)myocardial emission computed tomography(ECT) was performed following standard planar imaging in 45 patients(pts) with acute myocardial infarction(AMI). All of them had clinical, electrocardiographic and enzymatic evidence of AMI. The planar imaging and ECT imaging were interpreted independently by two observers who had no knowledge of the clinical findings. 10 pts(22.2 %), who showed diffuse uptake on planar imaging, revealed focal uptake on ECT imaging without cardiac blood pool imaging. And there is no disagreement as to interpretation of the infarct location by two observers on ECT imaging. We conclude that ECT imaging with Tc-99m-PYP increases interobserver agreement in the diagnosis and localization of AMI and may lead to more accurate localization and sizing of AMI, espesically in cases of diffuse cardiac activity on planar imaging. (author)

  10. Imaging spectrum and pitfalls of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with tuberculosis.

    Science.gov (United States)

    Ito, Kimiteru; Morooka, Miyako; Minamimoto, Ryogo; Miyata, Yoko; Okasaki, Momoko; Kubota, Kazuo

    2013-08-01

    Mycobacterium tuberculosis (TB) is one of the most prominant diseases frequently causing false positive lesions in oncologic surveys using (18)F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT), since TB granulomas are composed of activated macrophages and lymphocytes with high affinity for glucose. These pitfalls of (18)F-FDG PET/CT are important for radiologists. Being familiar with (18)F-FDG images of TB could assist in preventing unfavorable clinical results based on misdiagnoses. In addition, (18)F-FDG PET/CT has the advantage of being able to screen the whole body, and can clearly detect harboring TB lesions as high uptake foci. This article details the spectrum and pitfalls of (18)F-FDG PET/CT imaging in TB.

  11. Polyneoplasias in uveal melanoma patients detected by positron emission tomography combined with computed tomography (two clinical cases

    Directory of Open Access Journals (Sweden)

    K. V. Avakyan

    2017-01-01

    Full Text Available In addition to abdominal ultrasound and chest X-ray, positron emission tomography combined with computed tomography (PET/CT has been increasingly used to diagnose metastatic disease in patients with uveal melanoma. We present two clinical cases of the second malignancy (synchronous polyneoplasia, colon cancer that was eventually found during PET/CT in uveal melanoma patients performed to exclude dissemination of the neoplasm. It was shown that hybrid PET/CT is the most informative method in the diagnosis and monitoring of uveal melanoma patients. During one diagnostic procedure it enables to diagnose early stages of secondary malignancies, in addition to the assessment of metastatic dissemination.

  12. Dermatomyositis in a Patient with Cholangiocarcinoma Detected by an [(18)F]-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography Scan.

    Science.gov (United States)

    Suh, Koung Jin; Park, Jin Kyun; Cho, Seongcheol; Park, Hyunkyung; Baek, Hae Woon; Lee, Kyoungbun; Lee, Dong Soo; Lee, Kyung-Hun

    2016-04-01

    Cholangiocarcinoma with paraneoplastic dermatomyositis (DM) is extremely rare, and the whole body positron emission tomography-computed tomography (PET-CT) finding of paraneoplastic DM is rarely reported. We report a 66-year-old woman with metastatic cholangiocarcinoma, initially presented with bilateral proximal muscle uptake on PET-CT without clinical muscle symptoms. The initial interpretation of the high muscle uptake was metastasis to the muscles. However, while awaiting for chemotherapy, muscle weakness evolved and rapidly progressed. The level of creatine phosphokinase was significantly elevated. Electromyography revealed moderate myopathy, and a muscle biopsy showed degenerating myofibers with variable sizes. The diagnosis of paraneoplastic dermatomyositis was made. This case highlights that, although rare, paraneoplastic dermatomyositis can be present with cholangiocarcinoma. Also, muscle inflammation can precede the clinical muscle symptoms, and paraneoplastic DM should be considered as a possible differential diagnosis in the assessment of cancer patients who present with abnormal muscle tracer uptake in PET-CT scans.

  13. Computer simulation of ICP spectra: A new tool for the study of excitation, emission, and line overlap

    International Nuclear Information System (INIS)

    Blades, M.W.; Burton, L.L.

    1986-01-01

    It is well known that the relatively high temperature of ICP sources provides an excitation environment relatively free from dissociation and vaporization interferences and, in addition, produces intense analyte line spectra and hence high analytical sensitivity. However, this feature also introduces the potential for spectral overlaps from sample concomitants. The degree to which an analyte spectral line intensity can be corrected for interfering spectral overlaps depends on many factors including spectrometer resolution, sample composition and ICP operating conditions. The authors have been using a computer program to assist them in the study of ICP analyte emission spectra. This program is being used to study the spectral distribution of line intensity information and also to do detailed investigations on spectral overlaps in complex sample mixtures. As input data the program uses tabulated wavelengths, transition probabilities (gA values), partition functions, excitation energies of the transitions, ionization energy, temperature, and Doppler and Stark linewidths

  14. Lynch Syndrome Associated Colon Adenocarcinoma Resembling Lymphoma on Fluoro-Deoxyglucose-Positron Emission Tomography/Computed Tomography

    International Nuclear Information System (INIS)

    Aparici, Carina Mari; Win, Aung Zaw

    2015-01-01

    The patient was a 46-year-old Asian male diagnosed with lynch syndrome associated colon adenocarcinoma in the right ascending colon. A presurgical staging 18-fluoro-deoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) found increased metabolic activity in the cervical, axillary, mediastinal, supraclavicular, para-aortic and mesenteric lymph nodes. This pattern of metastasis was very unusual for lynch syndrome associated colon adenocarcinoma and the involvement of those lymph nodes resembles the pattern of spread of lymphoma. He underwent right hemicolectomy and he was subsequently treated with 12 cycles of folinic acid (leucovorin), fluorouracil (5-FU), irinotecan. A restaging FDG-PET/CT at the end of the chemotherapy showed interval decrease in size and metabolic activity in the affected lymph nodes. FDG-PET/CT is a useful imaging modality in following-up the treatment response in colon adenocarcinoma

  15. Alterations of Regional Cerebral Blood Flow in Tinnitus Patients as Assessed Using Single-Photon Emission Computed Tomography.

    Directory of Open Access Journals (Sweden)

    Takashi Ueyama

    Full Text Available Tinnitus is the perception of phantom sound without an external auditory stimulus. Using neuroimaging techniques, such as positron emission tomography, electroencephalography, magnetoencephalography, and functional magnetic resonance imaging (fMRI, many studies have demonstrated that abnormal functions of the central nervous system are closely associated with tinnitus. In our previous research, we reported using resting-state fMRI that several brain regions, including the rectus gyrus, cingulate gyrus, thalamus, hippocampus, caudate, inferior temporal gyrus, cerebellar hemisphere, and medial superior frontal gyrus, were associated with tinnitus distress and loudness. To reconfirm these results and probe target regions for repetitive transcranial magnetic stimulation (rTMS, we investigated the regional cerebral blood flow (rCBF between younger tinnitus patients (<60 years old and the age-matched controls using single-photon emission computed tomography and easy Z-score imaging system. Compared with that of controls, the rCBF of tinnitus patients was significantly lower in the bilateral medial superior frontal gyri, left middle occipital gyrus and significantly higher in the bilateral cerebellar hemispheres and vermis, bilateral middle temporal gyri, right fusiform gyrus. No clear differences were observed between tinnitus patients with normal and impaired hearing. Regardless of the assessment modality, similar brain regions were identified as characteristic in tinnitus patients. These regions are potentially involved in the pathophysiology of chronic subjective tinnitus.

  16. Performance of Positron Emission Tomography and Positron Emission Tomography/Computed Tomography Using Fluorine-18-Fluorodeoxyglucose for the Diagnosis, Staging, and Recurrence Assessment of Bone Sarcoma

    Science.gov (United States)

    Liu, Fanxiao; Zhang, Qingyu; Zhu, Dezhi; Li, Zhenfeng; Li, Jianmin; Wang, Boim; Zhou, Dongsheng; Dong, Jinlei

    2015-01-01

    Abstract To investigate the performance of fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) and PET/computed tomography (CT) in the diagnosis, staging, restaging, and recurrence surveillance of bone sarcoma by systematically reviewing and meta-analyzing the published literature. To retrieve eligible studies, we searched the MEDLINE, Embase, and the Cochrane Central library databases using combinations of following Keywords: “positron emission tomography” or “PET,” and “bone tumor” or “bone sarcoma” or “sarcoma.” Bibliographies from relevant articles were also screened manually. Data were extracted and the pooled sensitivity, specificity, and diagnostic odds ratio (DOR), on an examination-based or lesion-based level, were calculated to appraise the diagnostic accuracy of 18F-FDG PET and PET/CT. All statistical analyses were performed using Meta-Disc 1.4. Forty-two trials were eligible. The pooled sensitivity and specificity of PET/CT to differentiate primary bone sarcomas from benign lesions were 96% (95% confidence interval [CI], 93–98) and 79% (95% CI, 63–90), respectively. For detecting recurrence, the pooled results on an examination-based level were sensitivity 92% (95% CI, 85–97), specificity 93% (95% CI, 88–96), positive likelihood ratio (PLR) 10.26 (95% CI, 5.99–17.60), and negative likelihood ratio (NLR) 0.11 (95% CI, 0.05–0.22). For detecting distant metastasis, the pooled results on a lesion-based level were sensitivity 90% (95% CI, 86–93), specificity 85% (95% CI, 81–87), PLR 5.16 (95% CI, 2.37–11.25), and NLR 0.15 (95% CI, 0.11–0.20). The accuracies of PET/CT for detecting local recurrence, lung metastasis, and bone metastasis were satisfactory. Pooled outcome estimates of 18F-FDG PET were less complete compared with those of PET/CT. 18F-FDG PET and PET/CT showed a high sensitivity for diagnosing primary bone sarcoma. Moreover, PET/CT demonstrated excellent accuracy for the staging

  17. EFFAIR: a computer program for estimating the dispersion of atmospheric emissions from a nuclear site

    International Nuclear Information System (INIS)

    Dormuth, K.W.; Lyon, R.B.

    1978-11-01

    Analysis of the transport of material through the turbulent atmospheric boundary layer is an important part of environmental impact assessments for nuclear plants. Although this is a complex phenomenon, practical estimates of ground level concentrations downwind of release are usually obtained using a simple Gaussian formula whose coefficients are obtained from empirical correlations. Based on this formula, the computer program EFFAIR has been written to provide a flexible tool for atmospheric dispersion calculations. It is considered appropriate for calculating dilution factors at distances of 10 2 to 10 4 metres from an effluent source if reflection from the inversion lid is negligible in that range. (author)

  18. Image reconstruction in single photon emission computed tomography for radioactive waste testing

    International Nuclear Information System (INIS)

    Pouletaut, P.

    1993-02-01

    The aim of this study is to reconstruct by tomography the spatial distribution of the activity of an object which emits photons. First, an analysis of the imaging qualities of a tomograph in terms of physical parameters related to the measurement process is proposed. Then, an algorithm which evaluates, the self-attenuation of the emitted photons and corrects for the collimator aperture angle is developed; this computation corresponds to a subdivision of the object into voxels and to a parallel geometry of the projections. Two algebraic reconstruction methods have been studied; one using a regularized least-squares technique, the other using a bayesian approach. We show by computer simulations the dependence of the reconstruction on the condition number of the self-attenuation matrix and on the estimation errors of this matrix. Then, the reconstruction is tested on experimental data; the images we reconstruct on a square grid of ten by ten voxels from one hundred twenty measurements show an accurate location of the sources; their activities are efficiently estimated when the collimator aperture angle is well taken into account in the self-attenuation matrix

  19. Myocardial blood flow quantification for evaluation of coronary artery disease by positron emission tomography, cardiac magnetic resonance imaging, and computed tomography.

    Science.gov (United States)

    Waller, Alfonso H; Blankstein, Ron; Kwong, Raymond Y; Di Carli, Marcelo F

    2014-05-01

    The noninvasive detection of the presence and functional significance of coronary artery stenosis is important in the diagnosis, risk assessment, and management of patients with known or suspected coronary artery disease. Quantitative assessment of myocardial perfusion can provide an objective and reproducible estimate of myocardial ischemia and risk prediction. Positron emission tomography, cardiac magnetic resonance, and cardiac computed tomography perfusion are modalities capable of measuring myocardial blood flow and coronary flow reserve. In this review, we will discuss the technical aspects of quantitative myocardial perfusion imaging with positron emission tomography, cardiac magnetic resonance imaging, and computed tomography, and its emerging clinical applications.

  20. Deep searches for broadband extended gravitational-wave emission bursts by heterogeneous computing

    Science.gov (United States)

    van Putten, Maurice H. P. M.

    2017-09-01

    We present a heterogeneous search algorithm for broadband extended gravitational-wave emission, expected from gamma-ray bursts and energetic core-collapse supernovae. It searches the (f,\\dot{f})-plane for long-duration bursts by inner engines slowly exhausting their energy reservoir by matched filtering on a graphics processor unit (GPU) over a template bank of millions of 1 s duration chirps. Parseval's theorem is used to predict the standard deviation σ of the filter output, taking advantage of the near-Gaussian noise in the LIGO S6 data over 350-2000 Hz. Tails exceeding a multiple of σ are communicated back to a central processing unit. This algorithm attains about 65% efficiency overall, normalized to the fast Fourier transform. At about one million correlations per second over data segments of 16 s duration (N=2^{16} samples), better than real-time analysis is achieved on a cluster of about a dozen GPUs. We demonstrate its application to the capture of high-frequency hardware LIGO injections. This algorithm serves as a starting point for deep all-sky searches in both archive data and real-time analysis in current observational runs.

  1. Diagnostic performance of fluorodeoxyglucose positron emission tomography/magnetic resonance imaging fusion images of gynecological malignant tumors. Comparison with positron emission tomography/computed tomography

    International Nuclear Information System (INIS)

    Nakajo, Kazuya; Tatsumi, Mitsuaki; Inoue, Atsuo

    2010-01-01

    We compared the diagnostic accuracy of fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) and PET/magnetic resonance imaging (MRI) fusion images for gynecological malignancies. A total of 31 patients with gynecological malignancies were enrolled. FDG-PET images were fused to CT, T1- and T2-weighted images (T1WI, T2WI). PET-MRI fusion was performed semiautomatically. We performed three types of evaluation to demonstrate the usefulness of PET/MRI fusion images in comparison with that of inline PET/CT as follows: depiction of the uterus and the ovarian lesions on CT or MRI mapping images (first evaluation); additional information for lesion localization with PET and mapping images (second evaluation); and the image quality of fusion on interpretation (third evaluation). For the first evaluation, the score for T2WI (4.68±0.65) was significantly higher than that for CT (3.54±1.02) or T1WI (3.71±0.97) (P<0.01). For the second evaluation, the scores for the localization of FDG accumulation showing that T2WI (2.74±0.57) provided significantly more additional information for the identification of anatomical sites of FDG accumulation than did CT (2.06±0.68) or T1WI (2.23±0.61) (P<0.01). For the third evaluation, the three-point rating scale for the patient group as a whole demonstrated that PET/T2WI (2.72±0.54) localized the lesion significantly more convincingly than PET/CT (2.23±0.50) or PET/T1WI (2.29±0.53) (P<0.01). PET/T2WI fusion images are superior for the detection and localization of gynecological malignancies. (author)

  2. Computer simulation of energy use, greenhouse gas emissions, and costs for alternative methods of processing fluid milk.

    Science.gov (United States)

    Tomasula, P M; Datta, N; Yee, W C F; McAloon, A J; Nutter, D W; Sampedro, F; Bonnaillie, L M

    2014-07-01

    Computer simulation is a useful tool for benchmarking electrical and fuel energy consumption and water use in a fluid milk plant. In this study, a computer simulation model of the fluid milk process based on high temperature, short time (HTST) pasteurization was extended to include models for processes for shelf-stable milk and extended shelf-life milk that may help prevent the loss or waste of milk that leads to increases in the greenhouse gas (GHG) emissions for fluid milk. The models were for UHT processing, crossflow microfiltration (MF) without HTST pasteurization, crossflow MF followed by HTST pasteurization (MF/HTST), crossflow MF/HTST with partial homogenization, and pulsed electric field (PEF) processing, and were incorporated into the existing model for the fluid milk process. Simulation trials were conducted assuming a production rate for the plants of 113.6 million liters of milk per year to produce only whole milk (3.25%) and 40% cream. Results showed that GHG emissions in the form of process-related CO₂ emissions, defined as CO₂ equivalents (e)/kg of raw milk processed (RMP), and specific energy consumptions (SEC) for electricity and natural gas use for the HTST process alone were 37.6g of CO₂e/kg of RMP, 0.14 MJ/kg of RMP, and 0.13 MJ/kg of RMP, respectively. Emissions of CO2 and SEC for electricity and natural gas use were highest for the PEF process, with values of 99.1g of CO₂e/kg of RMP, 0.44 MJ/kg of RMP, and 0.10 MJ/kg of RMP, respectively, and lowest for the UHT process at 31.4 g of CO₂e/kg of RMP, 0.10 MJ/kg of RMP, and 0.17 MJ/kg of RMP. Estimated unit production costs associated with the various processes were lowest for the HTST process and MF/HTST with partial homogenization at $0.507/L and highest for the UHT process at $0.60/L. The increase in shelf life associated with the UHT and MF processes may eliminate some of the supply chain product and consumer losses and waste of milk and compensate for the small increases in GHG

  3. False-positive 18-fluorodeoxyglucose positron emission tomography–computed tomography (FDG PET/CT scans mimicking malignancies

    Directory of Open Access Journals (Sweden)

    Zehra Yasar

    2015-02-01

    Full Text Available Aim 18-Fluorodeoxyglucose (FDG positron emission tomography–computed tomography (PET/CT is an imaging modality that is often used to help differentiate benign from malignant pulmonary lesions and it has been shown to be more efficacious than conventional chest computed tomography (CT. However, some benign lesions may also show increased metabolic activity which can lead to false-positive PET findings. We aim to illustrate false positive findings of PET scan that simulate lung cancer in a variety of diseases. Methods Patients referred to Yedikule Chest Diseases and Surgery Teaching and Research Hospital with increased FDG uptake for which histological results were available over a 2-year period (2013-2014 were reviewed. Seven patients with false-positive PET/CT findings were reported in this study. Results The majority of lesions showing increased metabolic activity were due to malignant diseases. However, increased 18 F-FDG uptake was also seen in benign lesions such as active pulmonary inflammation or infection, granulomatous processes and fibrotic lesions. Conclusion. The integration of clinical history, morphologic findings of lesions on the CT component, and metabolic activities of PET/CT scan can help reduce false interpretations. Interventional procedures.

  4. Development of a Simple Image Processing Application that Makes Abdominopelvic Tumor Visible on Positron Emission Tomography/Computed Tomography Image.

    Science.gov (United States)

    Pandey, Anil Kumar; Saroha, Kartik; Sharma, Param Dev; Patel, Chetan; Bal, Chandrashekhar; Kumar, Rakesh

    2017-01-01

    In this study, we have developed a simple image processing application in MATLAB that uses suprathreshold stochastic resonance (SSR) and helps the user to visualize abdominopelvic tumor on the exported prediuretic positron emission tomography/computed tomography (PET/CT) images. A brainstorming session was conducted for requirement analysis for the program. It was decided that program should load the screen captured PET/CT images and then produces output images in a window with a slider control that should enable the user to view the best image that visualizes the tumor, if present. The program was implemented on personal computer using Microsoft Windows and MATLAB R2013b. The program has option for the user to select the input image. For the selected image, it displays output images generated using SSR in a separate window having a slider control. The slider control enables the user to view images and select one which seems to provide the best visualization of the area(s) of interest. The developed application enables the user to select, process, and view output images in the process of utilizing SSR to detect the presence of abdominopelvic tumor on prediuretic PET/CT image.

  5. Lung Hot Spot Without Corresponding Computed Tomography Abnormality on Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography: Artifactual or Real, Iatrogenic or Pathologic?

    Science.gov (United States)

    Liu, Yiyan

    Focal lung uptake without corresponding lesions or abnormalities on computed tomography (CT) scan poses a dilemma in the interpretation of fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT). A limited number of case reports have previously suggested an artifactual or iatrogenic nature of the uptake. In the present study, 8 relevant cases were included within a retrospective search of the database. Medical records were reviewed for follow-up radiological and pathologic information. In 7 of 8 cases with focal increased FDG uptake but no corresponding lesions or abnormalities on CT scan, the lung hot spots were artifactual or iatrogenic upon follow-up diagnostic chest CT or repeated PET/CT or both the scans. Microemboli were most likely a potential cause of the pulmonary uptake, with or without partial paravenous injection. One case in the series had a real pulmonary lesion demonstrated on follow-up PET/CT scans and on surgical pathology, although the initial integrated CT and follow-up diagnostic chest CT scans revealed negative findings to demonstrate pulmonary abnormalities corresponding to the hot spot on the PET scan. In conclusion, the finding of a lung hot spot in the absence of anatomical abnormality on FDG PET/CT was most likely artifactual or iatrogenic, but it might also represent a real pulmonary lesion. Nonvisualization of anatomical abnormality could be because of its small size and position directly overlying a segmental vessel. Further image follow-up is necessary and important to clarify the nature of the uptake. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Novel application of quantitative single-photon emission computed-tomography/computed tomography to predict early response to methimazole in Graves' disease

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Joo; Bang, Ji In; Kim, Ji Young; Moon, Jae Hoon [Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam (Korea, Republic of); So, Young [Dept. of Nuclear Medicine, Konkuk University Medical Center, Seoul (Korea, Republic of); Lee, Won Woo [Institute of Radiation Medicine, Medical Research Center, Seoul National University, Seoul (Korea, Republic of)

    2017-06-15

    Since Graves' disease (GD) is resistant to antithyroid drugs (ATDs), an accurate quantitative thyroid function measurement is required for the prediction of early responses to ATD. Quantitative parameters derived from the novel technology, single-photon emission computed tomography/computed tomography (SPECT/CT), were investigated for the prediction of achievement of euthyroidism after methimazole (MMI) treatment in GD. A total of 36 GD patients (10 males, 26 females; mean age, 45.3 ± 13.8 years) were enrolled for this study, from April 2015 to January 2016. They underwent quantitative thyroid SPECT/CT 20 minutes post-injection of {sup 99m}Tc-pertechnetate (5 mCi). Association between the time to biochemical euthyroidism after MMI treatment and uptake, standardized uptake value (SUV), functional thyroid mass (SUVmean × thyroid volume) from the SPECT/CT, and clinical/biochemical variables, were investigated. GD patients had a significantly greater %uptake (6.9 ± 6.4%) than historical control euthyroid patients (n = 20, 0.8 ± 0.5%, p < 0.001) from the same quantitative SPECT/CT protocol. Euthyroidism was achieved in 14 patients at 156 ± 62 days post-MMI treatment, but 22 patients had still not achieved euthyroidism by the last follow-up time-point (208 ± 80 days). In the univariate Cox regression analysis, the initial MMI dose (p = 0.014), %uptake (p = 0.015), and functional thyroid mass (p = 0.016) were significant predictors of euthyroidism in response to MMI treatment. However, only uptake remained significant in a multivariate Cox regression analysis (p = 0.034). A uptake cutoff of 5.0% dichotomized the faster responding versus the slower responding GD patients (p = 0.006). A novel parameter of thyroid uptake from quantitative SPECT/CT is a predictive indicator of an early response to MMI in GD patients.

  7. The Added Value of a Single-photon Emission Computed Tomography-Computed Tomography in Sentinel Lymph Node Mapping in Patients with Breast Cancer and Malignant Melanoma

    International Nuclear Information System (INIS)

    Bennie, George; Vorster, Mariza; Buscombe, John; Sathekge, Mike

    2015-01-01

    Single-photon emission computed tomography-computed tomography (SPECT-CT) allows for physiological and anatomical co-registration in sentinel lymph node (SLN) mapping and offers additional benefits over conventional planar imaging. However, the clinical relevance when considering added costs and radiation burden of these reported benefits remains somewhat uncertain. This study aimed to evaluate the possible added value of SPECT-CT and intra-operative gamma-probe use over planar imaging alone in the South African setting. 80 patients with breast cancer or malignant melanoma underwent both planar and SPECT-CT imaging for SLN mapping. We assessed and compared the number of nodes detected on each study, false positive and negative findings, changes in surgical approach and or patient management. In all cases where a sentinel node was identified, SPECT-CT was more accurate anatomically. There was a significant change in surgical approach in 30 cases - breast cancer (n = 13; P 0.001) and malignant melanoma (n = 17; P 0.0002). In 4 cases a node not identified on planar imaging was seen on SPECT-CT. In 16 cases additional echelon nodes were identified. False positives were excluded by SPECT-CT in 12 cases. The addition of SPECT-CT and use of intra-operative gamma-probe to planar imaging offers important benefits in patients who present with breast cancer and melanoma. These benefits include increased nodal detection, elimination of false positives and negatives and improved anatomical localization that ultimately aids and expedites surgical management. This has been demonstrated in the context of industrialized country previously and has now also been confirmed in the setting of a emerging-market nation

  8. Single photon emission computed tomography/spiral computed tomography fusion imaging for the diagnosis of bone metastasis in patients with known cancer

    International Nuclear Information System (INIS)

    Zhao, Zhen; Li, Lin; Li, Fanglan; Zhao, Lixia

    2010-01-01

    To evaluate single photon emission computed tomography (SPECT)/spiral computed tomography (CT) fusion imaging for the diagnosis of bone metastasis in patients with known cancer and to compare the diagnostic efficacy of SPECT/CT fusion imaging with that of SPECT alone and with SPECT + CT. One hundred forty-one bone lesions of 125 cancer patients (with nonspecific bone findings on bone scintigraphy) were investigated in the study. SPECT, CT, and SPECT/CT fusion images were acquired simultaneously. All images were interpreted independently by two experienced nuclear medicine physicians. In cases of discrepancy, consensus was obtained by a joint reading. The final diagnosis was based on biopsy proof and radiologic follow-up over at least 1 year. The final diagnosis revealed 63 malignant bone lesions and 78 benign lesions. The diagnostic sensitivity of SPECT, SPECT + CT, and SPECT/CT fusion imaging for malignant lesions was 82.5%, 93.7%, and 98.4%, respectively. Specificity was 66.7%, 80.8%, and 93.6%, respectively. Accuracy was 73.8%, 86.5%, and 95.7%, respectively. The specificity and accuracy of SPECT/CT fusion imaging for the diagnosis malignant bone lesions were significantly higher than those of SPECT alone and of SPECT + CT (P 2 = 9.855, P = 0.002). The numbers of equivocal lesions were 37, 18, and 5 for SPECT, SPECT + CT, and SPECT/CT fusion imaging, respectively, and 29.7% (11/37), 27.8% (5/18), and 20.0% (1/5) of lesions were confirmed to be malignant by radiologic follow-up over at least 1 year. SPECT/spiral CT is particularly valuable for the diagnosis of bone metastasis in patients with known cancer by providing precise anatomic localization and detailed morphologic characteristics. (orig.)

  9. Differentiation of myocardial ischemia and infarction assessed by dynamic computed tomography perfusion imaging and comparison with cardiac magnetic resonance and single-photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Tanabe, Yuki; Kido, Teruhito; Kurata, Akira; Miyagawa, Masao; Mochizuki, Teruhito [Ehime University Graduate School of Medicine, Department of Radiology, Toon, Ehime (Japan); Uetani, Teruyoshi; Kono, Tamami; Ogimoto, Akiyoshi [Ehime University Graduate School of Medicine, Department of Cardiology, Pulmonology, Hypertension and Nephrology, Toon, Ehime (Japan); Soma, Tsutomu [FUJIFILM RI Pharma Co., Ltd., QMS Group, Quality Assurance Department, Tokyo (Japan); Graduate School of Medicine, University of Tokyo, Department of Radiology, Tokyo (Japan); Murase, Kenya [Osaka University Graduate School of Medicine, Department of Medical Physics and Engineering, Division of Medical Technology and Science, Faculty of Health Science, Osaka (Japan); Iwaki, Hirotaka [Ehime University Graduate School of Medicine, Center for Clinical Research Data and Biostatistics, Toon, Ehime (Japan)

    2016-11-15

    To evaluate the feasibility of myocardial blood flow (MBF) by computed tomography from dynamic CT perfusion (CTP) for detecting myocardial ischemia and infarction assessed by cardiac magnetic resonance (CMR) or single-photon emission computed tomography (SPECT). Fifty-three patients who underwent stress dynamic CTP and either SPECT (n = 25) or CMR (n = 28) were retrospectively selected. Normal and abnormal perfused myocardium (ischemia/infarction) were assessed by SPECT/CMR using 16-segment model. Sensitivity and specificity of CT-MBF (mL/g/min) for detecting the ischemic/infarction and severe infarction were assessed. The abnormal perfused myocardium and severe infarction were seen in SPECT (n = 90 and n = 19 of 400 segments) and CMR (n = 223 and n = 36 of 448 segments). For detecting the abnormal perfused myocardium, sensitivity and specificity were 80 % (95 %CI, 71-90) and 86 % (95 %CI, 76-91) in SPECT (cut-off MBF, 1.23), and 82 % (95 %CI, 76-88) and 87 % (95 %CI, 80-92) in CMR (cut-off MBF, 1.25). For detecting severe infarction, sensitivity and specificity were 95 % (95 %CI, 52-100) and 72 % (95 %CI, 53-91) in SPECT (cut-off MBF, 0.92), and 78 % (95 %CI, 67-97) and 80 % (95 %CI, 58-86) in CMR (cut-off MBF, 0.98), respectively. Dynamic CTP has a potential to detect abnormal perfused myocardium and severe infarction assessed by SPECT/CMR using comparable cut-off MBF. (orig.)

  10. Correlation of uptake patterns on single-photon emission computed tomography/computed tomography (SPECT/CT)and treatment response in patients with knee pain

    Energy Technology Data Exchange (ETDEWEB)

    Koh, Geon; Hwang, Kyung Hoon; Lee, Hae Jin; Kim, Seog Gyun; Lee, Beom Koo [Gachon University Gil Hospital, Incheon (Korea, Republic of)

    2016-06-15

    To determine whether treatment response in patients with knee pain could be predicted using uptake patterns on single-photon emission computed tomography/computed tomography (SPECT/CT) images. Ninety-five patients with knee pain who had undergone SPECT/CT were included in this retrospective study. Subjects were divided into three groups: increased focal uptake (FTU), increased irregular tracer uptake (ITU), and no tracer uptake (NTU). A numeric rating scale (NRS-11) assessed pain intensity. We analyzed the association between uptake patterns and treatment response using Pearson's chi-square test and Fisher's exact test. Uptake was quantified from SPECT/CT with region of interest (ROI) counting, and an intraclass correlation coefficient (ICC) calculated agreement. We used Student' t-test to calculate statistically significant differences of counts between groups and the Pearson correlation to measure the relationship between counts and initial NRS-1k1. Multivariate logistic regression analysis determined which variables were significantly associated with uptake. The FTU group included 32 patients; ITU, 39; and NTU, 24. With conservative management, 64 % of patients with increased tracer uptake (TU, both focal and irregular) and 36 % with NTU showed positive response. Conservative treatment response of FTU was better than NTU, but did not differ from that of ITU. Conservative treatment response of TU was significantly different from that of NTU (OR 3.1; p 0.036). Moderate positive correlation was observed between ITU and initial NRS-11. Age and initial NRS-11 significantly predicted uptake. Patients with uptake in their knee(s) on SPECT/CT showed positive treatment response under conservative treatment.

  11. A tetrahedron beam computed tomography benchtop system with a multiple pixel field emission x-ray tube.

    Science.gov (United States)

    Xu, Xiaochao; Kim, Joshua; Laganis, Philip; Schulze, Derek; Liang, Yongguang; Zhang, Tiezhi

    2011-10-01

    To demonstrate the feasibility of Tetrahedron Beam Computed Tomography (TBCT) using a carbon nanotube (CNT) multiple pixel field emission x-ray (MPFEX) tube. A multiple pixel x-ray source facilitates the creation of novel x-ray imaging modalities. In a previous publication, the authors proposed a Tetrahedron Beam Computed Tomography (TBCT) imaging system which comprises a linear source array and a linear detector array that are orthogonal to each other. TBCT is expected to reduce scatter compared with Cone Beam Computed Tomography (CBCT) and to have better detector performance. Therefore, it may produce improved image quality for image guided radiotherapy. In this study, a TBCT benchtop system has been developed with an MPFEX tube. The tube has 75 CNT cold cathodes, which generate 75 x-ray focal spots on an elongated anode, and has 4 mm pixel spacing. An in-house-developed, 5-row CT detector array using silicon photodiodes and CdWO(4) scintillators was employed in the system. Hardware and software were developed for tube control and detector data acquisition. The raw data were preprocessed for beam hardening and detector response linearity and were reconstructed with an FDK-based image reconstruction algorithm. The focal spots were measured at about 1 × 2 mm(2) using a star phantom. Each cathode generates around 3 mA cathode current with 2190 V gate voltage. The benchtop system is able to perform TBCT scans with a prolonged scanning time. Images of a commercial CT phantom were successfully acquired. A prototype system was developed, and preliminary phantom images were successfully acquired. MPFEX is a promising x-ray source for TBCT. Further improvement of tube output is needed in order for it to be used in clinical TBCT systems.

  12. Quantitative exercise thallium-201 single photon emission computed tomography for the enhanced diagnosis of ischemic heart disease

    International Nuclear Information System (INIS)

    Mahmarian, J.J.; Boyce, T.M.; Goldberg, R.K.; Cocanougher, M.K.; Roberts, R.; Verani, M.S.

    1990-01-01

    The clinical utility of exercise thallium-201 single photon emission computed tomography was investigated in 360 consecutive patients who had concomitant coronary arteriography. Tomographic images were assessed visually and from computer-quantified polar maps. Sensitivity for detecting coronary artery disease was comparably high using quantitative and visual analysis, although specificity tended to improve using the former method (87% versus 76%, p = 0.09). Quantitative analysis was superior to the visual method for identifying left anterior descending (81% versus 68%, p less than 0.05) and circumflex coronary artery (77% versus 60%, p less than 0.05) stenoses and detected most patients (92%) with multivessel coronary artery disease. Multivessel involvement was correctly predicted in 65% of the patients with more than one critically stenosed vessel. Exercise variables in patients with significant coronary artery disease were similar whether the tomographic images were normal or abnormal. However, patients with coronary stenoses and normal versus abnormal tomograms had a trend toward more single vessel disease (79% versus 62%, p = 0.07) and moderate coronary stenosis (66% versus 28%, p less than 0.001), but had less proximal left anterior descending artery involvement (8% versus 34%, p = 0.05). Computer-quantified perfusion defect size was directly related to the extent of coronary artery disease. Intra- and interobserver agreement for quantifying defects were excellent (r = 0.98 and 0.97, respectively). In conclusion, quantitative thallium-201 tomography offers improved detection of coronary artery disease, localization of the anatomic site of coronary stenosis, prediction of multivessel involvement and accurate determination of perfusion defect size, while maintaining a high specificity

  13. Comparison of 18F-fluorodeoxyglucose positron emission tomography/computed tomography, hydro-stomach computed tomography, and their combination for detecting primary gastric cancer

    International Nuclear Information System (INIS)

    Jang, Hye Young; Chung, Woo Suk; Song, E Rang; Kim, Jin Suk

    2015-01-01

    To retrospectively compare the diagnostic accuracy for detecting primary gastric cancer on positron emission tomography/computed tomography (PET/CT) and hydro-stomach CT (S-CT) and determine whether the combination of the two techniques improves diagnostic performance. A total of 253 patients with pathologically proven primary gastric cancer underwent PET/CT and S-CT for the preoperative evaluation. Two radiologists independently reviewed the three sets (PET/CT set, S-CT set, and the combined set) of PET/CT and S-CT in a random order. They graded the likelihood for the presence of primary gastric cancer based on a 4-point scale. The diagnostic accuracy of the PET/CT set, the S-CT set, and the combined set were determined by the area under the alternative-free receiver operating characteristic curve, and sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Diagnostic accuracy, sensitivity, and NPV for detecting all gastric cancers and early gastric cancers (EGCs) were significantly higher with the combined set than those with the PET/CT and S-CT sets. Specificity and PPV were significantly higher with the PET/CT set than those with the combined and S-CT set for detecting all gastric cancers and EGCs. The combination of PET/CT and S-CT is more accurate than S-CT alone, particularly for detecting EGCs.

  14. Improvement of in vivo quantification of [123I]-Iodobenzovesamicol in single-photon emission computed tomography/computed tomography using anatomic image to brain atlas nonrigid registration.

    Science.gov (United States)

    Lamare, Frederic; Mazere, Joachim; Attila, Mathieu; Mayo, Willy; De Clermont-Gallerande, Henri; Meissner, Wassilios; Fernandez, Philippe; Allard, Michele

    2013-01-01

    Brain anatomy variability is a major problem in quantifying functional images in nuclear medicine, in particular relative to aging and neurodegenerative diseases. The aim of this study was to compare affine and elastic model-based methods for magnetic resonance imaging (MRI) to brain atlas registration and to assess their impact on the quantification of cholinergic neurotransmission. Patients with multiple system atrophy (MSA) and age-matched healthy subjects underwent an MRI and a single-photon emission computed tomographic (SPECT) examination using [123I]-iodobenzovesamicol (IBVM). Both affine and elastic methods were compared to register the subjects' MRI with the Montreal Neurological Institute brain atlas. Performance of the registration accuracy was quantitatively assessed and the impact on the IBVM quantification was studied. For both subject groups, elastic registration achieved better quantitative performance compared to the affine model. For patients suffering from neurogenerative disease, this study demonstrates the importance and relevance of MRI to atlas registration in quantification of neuronal integrity. In this context, in comparison with rigid registrations, an elastic model-based registration provides the best relocation of the brain structures to the atlas for accurately quantifying cholinergic neurotransmission.

  15. Comparison of {sup 18}F-fluorodeoxyglucose positron emission tomography/computed tomography, hydro-stomach computed tomography, and their combination for detecting primary gastric cancer

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Hye Young; Chung, Woo Suk; Song, E Rang; Kim, Jin Suk [Konyang University Myunggok Medical Research Institute, Konyang University Hospital, Konyang University College of Medicine, Daejeon (Korea, Republic of)

    2015-01-15

    To retrospectively compare the diagnostic accuracy for detecting primary gastric cancer on positron emission tomography/computed tomography (PET/CT) and hydro-stomach CT (S-CT) and determine whether the combination of the two techniques improves diagnostic performance. A total of 253 patients with pathologically proven primary gastric cancer underwent PET/CT and S-CT for the preoperative evaluation. Two radiologists independently reviewed the three sets (PET/CT set, S-CT set, and the combined set) of PET/CT and S-CT in a random order. They graded the likelihood for the presence of primary gastric cancer based on a 4-point scale. The diagnostic accuracy of the PET/CT set, the S-CT set, and the combined set were determined by the area under the alternative-free receiver operating characteristic curve, and sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Diagnostic accuracy, sensitivity, and NPV for detecting all gastric cancers and early gastric cancers (EGCs) were significantly higher with the combined set than those with the PET/CT and S-CT sets. Specificity and PPV were significantly higher with the PET/CT set than those with the combined and S-CT set for detecting all gastric cancers and EGCs. The combination of PET/CT and S-CT is more accurate than S-CT alone, particularly for detecting EGCs.

  16. An X-Ray computed tomography/positron emission tomography system designed specifically for breast imaging.

    Science.gov (United States)

    Boone, John M; Yang, Kai; Burkett, George W; Packard, Nathan J; Huang, Shih-ying; Bowen, Spencer; Badawi, Ramsey D; Lindfors, Karen K

    2010-02-01

    Mammography has served the population of women who are at-risk for breast cancer well over the past 30 years. While mammography has undergone a number of changes as digital detector technology has advanced, other modalities such as computed tomography have experienced technological sophistication over this same time frame as well. The advent of large field of view flat panel detector systems enable the development of breast CT and several other niche CT applications, which rely on cone beam geometry. The breast, it turns out, is well suited to cone beam CT imaging because the lack of bones reduces artifacts, and the natural tapering of the breast anteriorly reduces the x-ray path lengths through the breast at large cone angle, reducing cone beam artifacts as well. We are in the process of designing a third prototype system which will enable the use of breast CT for image guided interventional procedures. This system will have several copies fabricated so that several breast CT scanners can be used in a multi-institutional clinical trial to better understand the role that this technology can bring to breast imaging.

  17. Variabilities of Magnetic Resonance Imaging-, Computed Tomography-, and Positron Emission Tomography-Computed Tomography-Based Tumor and Lymph Node Delineations for Lung Cancer Radiation Therapy Planning.

    Science.gov (United States)

    Karki, Kishor; Saraiya, Siddharth; Hugo, Geoffrey D; Mukhopadhyay, Nitai; Jan, Nuzhat; Schuster, Jessica; Schutzer, Matthew; Fahrner, Lester; Groves, Robert; Olsen, Kathryn M; Ford, John C; Weiss, Elisabeth

    2017-09-01

    To investigate interobserver delineation variability for gross tumor volumes of primary lung tumors and associated pathologic lymph nodes using magnetic resonance imaging (MRI), and to compare the results with computed tomography (CT) alone- and positron emission tomography (PET)-CT-based delineations. Seven physicians delineated the tumor volumes of 10 patients for the following scenarios: (1) CT only, (2) PET-CT fusion images registered to CT ("clinical standard"), and (3) postcontrast T1-weighted MRI registered with diffusion-weighted MRI. To compute interobserver variability, the median surface was generated from all observers' contours and used as the reference surface. A physician labeled the interface types (tumor to lung, atelectasis (collapsed lung), hilum, mediastinum, or chest wall) on the median surface. Contoured volumes and bidirectional local distances between individual observers' contours and the reference contour were analyzed. Computed tomography- and MRI-based tumor volumes normalized relative to PET-CT-based volumes were 1.62 ± 0.76 (mean ± standard deviation) and 1.38 ± 0.44, respectively. Volume differences between the imaging modalities were not significant. Between observers, the mean normalized volumes per patient averaged over all patients varied significantly by a factor of 1.6 (MRI) and 2.0 (CT and PET-CT) (P=4.10 × 10 -5 to 3.82 × 10 -9 ). The tumor-atelectasis interface had a significantly higher variability than other interfaces for all modalities combined (P=.0006). The interfaces with the smallest uncertainties were tumor-lung (on CT) and tumor-mediastinum (on PET-CT and MRI). Although MRI-based contouring showed overall larger variability than PET-CT, contouring variability depended on the interface type and was not significantly different between modalities, despite the limited observer experience with MRI. Multimodality imaging and combining different imaging characteristics might be the best approach to define

  18. The added value of 18F-fluorodeoxyglucose positron emission tomography computed tomography in patients with neck lymph node metastases from an unknown primary malignancy.

    Science.gov (United States)

    Prowse, S J B; Shaw, R; Ganeshan, D; Prowse, P M; Hanlon, R; Lewis-Jones, H; Wieshmann, H

    2013-08-01

    The search for a primary malignancy in patients with a metastatic cervical lymph node is challenging yet ultimately of utmost clinical importance. This study evaluated the efficacy of positron emission tomography computed tomography in detecting the occult primary, within the context of a tertiary referral centre head and neck cancer multidisciplinary team tumour board meeting. Thirty-two patients (23 men and 9 women; mean and median age, 61 years) with a metastatic cervical lymph node of unknown primary origin, after clinical examination and magnetic resonance imaging, underwent positron emission tomography computed tomography. The primary tumour detection rate was 50 per cent (16/32). Positron emission tomography computed tomography had a sensitivity of 94 per cent (16/17) and a specificity of 67 per cent (10/15). Combining these results with those of 10 earlier studies of similar patients gave an overall detection rate of 37 per cent. Positron emission tomography computed tomography has become an important imaging modality. To date, it has the highest primary tumour detection rate, for head and neck cancer patients presenting with cervical lymph node metastases from an unknown primary.

  19. Preliminary experience with thallous chloride T1 201-labeled single-photon emission computed tomography scanning in head and neck cancer

    NARCIS (Netherlands)

    Gregor, R. T.; Valdés-Olmos, R.; Koops, W.; Balm, A. J.; Hilgers, F. J.; Hoefnagel, C. A.

    1996-01-01

    To test the feasibility of single-photon emission computed tomography (SPECT) scanning with the use of thallous chloride T1 201 in patients with head and neck cancer and to decide its possible applications to improve the diagnosis and staging of head and neck cancer. Findings from SPECT with the use

  20. [(18)F]-fluorocholine positron-emission/computed tomography for lymph node staging of patients with prostate cancer: preliminary results of a prospective study

    DEFF Research Database (Denmark)

    Poulsen, Mads H; Bouchelouche, Kirsten; Gerke, Oke

    2010-01-01

    Study Type - Diagnostic (case series) Level of Evidence 4 OBJECTIVES To evaluate prospectively [(18)F]-fluorocholine positron-emission/computed tomography (FCH PET/CT) for lymph node staging of prostate cancer before intended curative therapy, and to determine whether imaging 15 or 60 min after...

  1. Correction of an image size difference between positron emission tomography (PET) and computed tomography (CT) improves image fusion of dedicated PET and CT.

    NARCIS (Netherlands)

    Vogel, W.V.; Dalen, J.A. van; Schinagl, D.A.X.; Kaanders, J.H.A.M.; Huisman, H.J.; Corstens, F.H.M.; Oyen, W.J.G.

    2006-01-01

    AIM: Clinical work in software positron emission tomography/computed tomography (PET/CT) image fusion has raised suspicion that the image sizes of PET and CT differ slightly from each other, thus rendering the images suboptimal for image fusion. The aim of this study was to evaluate the extent of

  2. Assessment of neuroinflammation and microglial activation in Alzheimer's disease with radiolabelled PK11195 and single photon emission computed tomography - A Pilot Study

    NARCIS (Netherlands)

    Versijpt, JJ; Dumont, F; Van Laere, KJ; Decoo, D; Santens, P; Audenaert, K; Achten, E; Slegers, G; Dierckx, RA; Korf, J

    2003-01-01

    Objectives: Inflammation contributes to degeneration in Alzheimer's disease (AD), not simply as a secondary phenomenon, but primarily as a significant source of pathology. [I-123]iodo-PK11195 is a single photon emission computed tomography (SPECT) ligand for the peripheral benzodiazepine receptor,

  3. (18)F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography in Malignancies of the Thyroid and in Head and Neck Squamous Cell Carcinoma

    DEFF Research Database (Denmark)

    Lauridsen, Jeppe Kiilerich; Rohde, Max; Thomassen, Anders

    2015-01-01

    18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) is a valuable diagnostic tool in a spectrum of malignant and benign conditions, because of a high sensitivity to detect even very small lesions with increased metabolism. This review focuses on the use of FDG...

  4. Development of Laser Application Technology for Stable Isotope Production

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Do Young; Ko, Kwang Hoon; Kwon, Duck Hee [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)] (and others)

    2007-04-15

    Tl-203 is used as a source material to produce Tl-201 radioisotope which is produced in a cyclotron by irradiating the enriched Tl-203 target. Tl-201 is a radiopharmaceutical for SPECT (single photon emission computerized tomography) to diagnose heart diseases and tumors. This Project aim to develop laser application technology to product stable isotopes such as Tl-203, Yb-168, and Yb-176. For this, photoion extraction device, atomic beam generator, dye lasers, and high power IR lasers are developed.

  5. Comparing staging by positron emission tomography with contrast-enhanced computed tomography and by pathology in head and neck squamous cell carcinoma.

    Science.gov (United States)

    Qualliotine, J R; Mydlarz, W K; Chan, J Y K; Zhou, X; Wang, H; Agrawal, N

    2015-12-01

    This study aimed to evaluate the ability of positron emission tomography with contrast-enhanced computed tomography to correctly stage head and neck squamous cell carcinomas, in comparison with pathological staging. Positron emission tomography computed tomography was used to determine the tumour-node-metastasis classification and overall cancer stage in 85 head and neck squamous cell carcinoma patients who underwent pre-operative imaging using this modality and primary surgery between July 2010 and January 2013. Staging by positron emission tomography computed tomography was retrospectively compared with staging using pathological specimens. Agreement between imaging stage and pathological stage was examined by univariate and multivariate analysis both overall and for each primary tumour site. This imaging modality was 87.5 per cent sensitive and 44.8 per cent specific in identifying regional cervical metastases, and had false positive and false negative rates of 18.8 per cent and 8.2 per cent, respectively. The positive predictive and negative predictive values were 75.4 per cent and 65.0 per cent, respectively. Univariate and multivariate analyses revealed a significant agreement between positron emission tomography computed tomography and pathological node classification in older patients and for the oral cavity primary tumour site. There was significant agreement between both methods in the overall classification only for tumours classified as T3 or greater. Positron emission tomography computed tomography should be used with caution for the pre-operative staging of head and neck cancers because of its high false positive and false negative rates.

  6. DIAGNOSTIC ROLE OF FLUORINE-18 (18F) FLUORODEOXYGLUCOSE POSITRON EMISSION TOMOGRAPHY COMPUTED TOMOGRAPHY IN DETECTING RECURRENT DISEASE IN PATIENTS WITH COLORECTAL CANCER AND ELEVATED CARCINOEMBRYONIC ANTIGEN.

    Science.gov (United States)

    Matovina, Emil; Mihailović, Jasna; Nikoletić, Katarina; Srbovan, Dolores

    2015-01-01

    Early detection of recurrence is an important factor for long term survival of patients with colorectal cancer. Measurement of serum levels of carcinoembryonic antigen has been commonly used in the postoperative surveillance of colorectal cancer. The purpose of this study was to evaluate the ability of positron emission tomography-computed tomography to detect pathological substrate of elevated serum carcinoembryonic antigen in patients with colorectal cancer. The patients with colorectal cancer who underwent curative surgical resection and/ or chemotherapy, who were found in our database, were analyzed retrospectively. Forty-eight 18F-fluorodeoxyglucose positron emission tomography-computed tomography studies including 45 patients (14 women, 31 men; mean age: 62.93 years) with elevated serum, carcinoembryonic antigen levels, which had been performed between January 2011 and January 2014, were evaluated. Serum levels of carcinoembryonic antigen were measured within 3 months after positron emission tomography-computed tomography examination. Final diagnosis of recurrence was made by histopathological findings, radiology studies or clinical follow-up. Recurrences were diagnosed in 37 patients, the prevalence being 77.1%. Liver metastases were found in 18 patients, abdominal, pelvic and/or mediastinal lymph nodes were positive in 19 patients, 11 patients had loco regional recurrences and 4 patients had pulmonary metastasis, and bone metastases were found in one patient. One patient was diagnosed with metastasis in scar tissue. The overall sensitivity and specificity of positron emission tomography-computed tomography was 90.24% and 71.42%, respectively. The positive and negative predictive values were 94.87% and 55.56%, respectively. 18F-fluorodeoxyglucose positron emission tomography-computed tomography is a powerful tool that could be used in determining colorectal cancer recurrence in patients with elevated carcinoembryonic antigen levels and could have an

  7. New computer-aided diagnosis of dementia using positron emission tomography: brain regional sensitivity-mapping method.

    Directory of Open Access Journals (Sweden)

    Akihiro Kakimoto

    Full Text Available PURPOSE: We devised a new computer-aided diagnosis method to segregate dementia using one estimated index (Total Z score derived from the Brodmann area (BA sensitivity map on the stereotaxic brain atlas. The purpose of this study is to investigate its accuracy to differentiate patients with Alzheimer's disease (AD or mild cognitive impairment (MCI from normal adults (NL. METHODS: We studied 101 adults (NL: 40, AD: 37, MCI: 24 who underwent (18FDG positron emission tomography (PET measurement. We divided NL and AD groups into two categories: a training group with (Category A and a test group without (Category B clinical information. In Category A, we estimated sensitivity by comparing the standard uptake value per BA (SUVR between NL and AD groups. Then, we calculated a summated index (Total Z score by utilizing the sensitivity-distribution maps and each BA z-score to segregate AD patterns. To confirm the validity of this method, we examined the accuracy in Category B. Finally, we applied this method to MCI patients. RESULTS: In Category A, we found that the sensitivity and specificity of differentiation between NL and AD were all 100%. In Category B, those were 100% and 95%, respectively. Furthermore, we found this method attained 88% to differentiate AD-converters from non-converters in MCI group. CONCLUSIONS: The present automated computer-aided evaluation method based on a single estimated index provided good accuracy for differential diagnosis of AD and MCI. This good differentiation power suggests its usefulness not only for dementia diagnosis but also in a longitudinal study.

  8. Low Accuracy of Computed Tomography and Positron Emission Tomography to Detect Lung and Lymph Node Metastases of Colorectal Cancer.

    Science.gov (United States)

    Guerrera, Francesco; Renaud, Stéphane; Schaeffer, Mickaël; Nigra, Victor; Solidoro, Paolo; Santelmo, Nicola; Filosso, Pier Luigi; Falcoz, Pierre-Emmanuel; Ruffini, Enrico; Oliaro, Alberto; Massard, Gilbert

    2017-10-01

    Minimally invasive surgery, stereotactic radiotherapy, and radiofrequency ablation are commonly proposed in the case of pulmonary colorectal-metastasis as alternatives to conventional open surgery. Preoperative imaging assessment by computed tomography (CT) scan and fluorodeoxyglucose positron emission tomography (FDG-PET) are critical to guide oncologic radical treatment. Our aim was to investigate the accuracy of CT and FDG-PET for the evaluation of the number of pulmonary colorectal metastases and thoracic lymph nodal involvement (LNI). Patients who underwent lung surgical resection for pulmonary colorectal metastases from 2004 to 2014 were analyzed. Concordance between histology, CT scan, and FDG-PET findings were assessed. Data of 521 patients were analyzed. Of those, FDG-PET was performed in 435 (83.5%). A moderate agreement between both CT scan (kappa index: 0.42) and FDG-PET (kappa index: 0.42) findings and the histologically proven number of metastases was observed. The number of histologically proven metastases was correctly discriminated in 61.7% of cases with CT scan and in 61.8% of cases with FDG-PET. Multiple metastases were discovered in 20.9% of clinical single metastasis cases with CT scan, and in 24.4% of those cases with FDG-PET. One hundred fifty patients (29.1%) presented with pathologic LNI. A poor agreement was observed between LNI and CT scan findings (kappa index: 0.02), and a weak agreement was observed concerning LNI and FDG-PET findings (kappa index: 0.39). Computed tomography and FDG-PET have limitations if the objective is to detect all malignant nodules and to discriminate the LNI in cases of pulmonary metastases of colorectal cancer. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  9. New Computer-Aided Diagnosis of Dementia Using Positron Emission Tomography: Brain Regional Sensitivity-Mapping Method

    Science.gov (United States)

    Kakimoto, Akihiro; Kamekawa, Yuichi; Ito, Shigeru; Yoshikawa, Etsuji; Okada, Hiroyuki; Nishizawa, Sadahiko; Minoshima, Satoshi; Ouchi, Yasuomi

    2011-01-01

    Purpose We devised a new computer-aided diagnosis method to segregate dementia using one estimated index (Total Z score) derived from the Brodmann area (BA) sensitivity map on the stereotaxic brain atlas. The purpose of this study is to investigate its accuracy to differentiate patients with Alzheimer's disease (AD) or mild cognitive impairment (MCI) from normal adults (NL). Methods We studied 101 adults (NL: 40, AD: 37, MCI: 24) who underwent 18FDG positron emission tomography (PET) measurement. We divided NL and AD groups into two categories: a training group with (Category A) and a test group without (Category B) clinical information. In Category A, we estimated sensitivity by comparing the standard uptake value per BA (SUVR) between NL and AD groups. Then, we calculated a summated index (Total Z score) by utilizing the sensitivity-distribution maps and each BA z-score to segregate AD patterns. To confirm the validity of this method, we examined the accuracy in Category B. Finally, we applied this method to MCI patients. Results In Category A, we found that the sensitivity and specificity of differentiation between NL and AD were all 100%. In Category B, those were 100% and 95%, respectively. Furthermore, we found this method attained 88% to differentiate AD-converters from non-converters in MCI group. Conclusions The present automated computer-aided evaluation method based on a single estimated index provided good accuracy for differential diagnosis of AD and MCI. This good differentiation power suggests its usefulness not only for dementia diagnosis but also in a longitudinal study. PMID:21966405

  10. {sup 18}F-fluorodeoxyglucose positron emission tomography-computed tomography in the management of adult multisystem Langerhans cell histiocytosis

    Energy Technology Data Exchange (ETDEWEB)

    Obert, Julie [Universite Paris Diderot, Paris (France); Assistance Publique-Hopitaux de Paris, Centre National de Reference de l' Histiocytose Langerhansienne, Service de Pneumologie, Hopital Saint-Louis, Paris (France); Vercellino, Laetitia [Assistance Publique-Hopitaux de Paris, Service de Medecine Nucleaire, Hopital Saint-Louis, Paris (France); Van der Gucht, Axel [Universite Paris Diderot, Paris (France); Assistance Publique-Hopitaux de Paris, Service de Medecine Nucleaire, Hopital Saint-Louis, Paris (France); De Margerie-Mellon, Constance [Universite Paris Diderot, Paris (France); Assistance Publique-Hopitaux de Paris, Service de Radiologie, Hopital Saint-Louis, Paris (France); Bugnet, Emmanuelle; Lorillon, Gwenael [Assistance Publique-Hopitaux de Paris, Centre National de Reference de l' Histiocytose Langerhansienne, Service de Pneumologie, Hopital Saint-Louis, Paris (France); Chevret, Sylvie [Universite Paris Diderot, Paris (France); Assistance Publique-Hopitaux de Paris, Service de Biostatistique et Information Medicale, Hopital Saint-Louis, Paris (France); Biostatistics and Clinical Epidemiology Research Team, U1153 CRESS, Paris (France); Tazi, Abdellatif [Universite Paris Diderot, Paris (France); Assistance Publique-Hopitaux de Paris, Centre National de Reference de l' Histiocytose Langerhansienne, Service de Pneumologie, Hopital Saint-Louis, Paris (France); Biostatistics and Clinical Epidemiology Research Team, U1153 CRESS, Paris (France)

    2017-04-15

    The standard evaluation of multisystem Langerhans cell histiocytosis (LCH) includes a clinical evaluation, laboratory tests and a skeleton/skull X-ray survey, with chest high-resolution computed tomography (HRCT) in the case of pulmonary involvement. Preliminary reports suggest that {sup 18}F-fluorodeoxyglucose positron emission tomography-computed tomography ({sup 18}F-FDG PET-CT) may be useful for evaluating patients with LCH. Fourteen consecutive adult patients with multisystem LCH were included in this retrospective study, and were evaluated using standard procedures and {sup 18}F-FDG PET-CT. The two sets of findings were compared both at baseline and during follow-up. Serial HRCT and pulmonary function tests were used to evaluate outcome in patients with lung involvement. At the baseline evaluation, PET-CT identified every LCH localization found with the standard evaluation (except a mild cecum infiltration). PET-CT showed additional lesions in seven patients, mostly involving bones, and differentiated inactive from active lesions. Thyroid {sup 18}F-FDG uptake was identified in three cases. No pituitary stalk {sup 18}F-FDG uptake was observed in patients with pituitary LCH. Only 3/12 (25 %) patients with pulmonary LCH displayed moderate pulmonary {sup 18}F-FDG uptake. During follow-up, variations (≥50 % of maximum standardized uptake) in bone {sup 18}F-FDG uptake intensity were correlated with disease state and response to treatment. The absence of lung {sup 18}F-FDG uptake did not preclude lung function improvement after treatment. Except for cases with pulmonary and pituitary involvement, {sup 18}F-FDG PET-CT could replace the standard evaluation for staging of adult patients with multisystem LCH. Serial PET-CT scans are useful for evaluating treatment responses, particularly in cases with bone LCH involvement. (orig.)

  11. Increased fluoro-deoxy-D-glucose uptake on positron emission tomography-computed tomography postbronchoalveolar lavage: a potential cause of radiologic misinterpretation.

    LENUS (Irish Health Repository)

    Leong, Sum

    2011-08-01

    Cytologic analysis of bronchoalveolar lavage (BAL) fluid is used for lung cancer diagnosis. We describe a patient with a history of rectal carcinoma who presented with a new lung mass. BAL was performed, with positron emission tomography-computed tomography the following day. There was mildly increased fluoro-deoxy-D-glucose uptake in areas of the lung parenchyma with new ground-glass opacification. This created ambiguity in staging, clarified 2 weeks later by a computed tomography showing complete resolution of the ground-glass opacity. Clinicians should be aware that BAL may cause increased pulmonary fluoro-deoxy-D-glucose uptake, making accurate radiologic interpretation problematic. We suggest that to optimize positron emission tomography-computed tomography, studies should not be performed within 24 hours of BAL.

  12. Osseous vitality in single photon emission computed tomography/computed tomography (SPECT/CT) after balloon tibioplasty of the tibial plateau: a case series.

    Science.gov (United States)

    Jentzsch, Thorsten; Fritz, Yannick; Veit-Haibach, Patrick; Schmitt, Jürgen; Sprengel, Kai; Werner, Clément M L

    2015-11-17

    The minimally invasive, balloon-assisted reduction and cement-augmented internal fixation of the tibial plateau is an innovative surgical procedure for tibial plateau fractures. The close proximity of balloons and cement to the knee joint poses a potential risk for osteonecrosis; especially in the case of thin bone lamellae. However, there are no studies about the vitality of the cement-surrounding tissue after these tibioplasties. Therefore, our goal was to assess the osseous vitality after cement-augmented balloon tibioplasty using single photon emission computed tomography/computed tomography (SPECT/CT) in a series of patients. This case series evaluated available consecutive patients, whose tibial plateau fractures were treated with balloon-assisted, cement-augmented tibioplasty and received a SPECT/CT. Primary outcome variables were osseous vitality on SPECT/CTs according to the semiquantitative tracer activity analysis. The mean uptake of eight tibial regions of interest was referenced to the mean uptake count on the same region of the contralateral leg to obtain a count ratio. Osteonecrosis was defined as a photopenic area or cold defect. Secondary variables included clinical and radiological follow-up data. Statistics were carried out in a descriptive pattern. Ten patients with a mean age of 59 years and a mean follow up of 18 months were included. Calcium phosphate (CaP) substitute bone cement was used in 60% and polymethyl methacrylate mixed with hydroxyapatite (PMMA/HA) bone cement in 40%. Normal to high SPECT/CT activity without photopenic areas were observed in all patients and the mean tracer activity ratio was four, indicating vital bone in all patients. There were no postoperative infections and only one 57 year old patient with hemineglect and CaP cement showed failed osseous consolidation. The mean Tegner and Lysholm as well as the Lysholm scores were three and 80, respectively. This novel study about cement-augmented balloon tibioplasties showed

  13. Evaluative studies in nuclear medicine research: emission computed tomography assessment. Final report, January 1-December 31, 1981

    International Nuclear Information System (INIS)

    Potchen, E.J.; Harris, G.I.; Gift, D.A.; Reinhard, D.K.; Siebert, J.E.

    1981-12-01

    The report provides information on an assessment of the potential short and long term benefits of emission computed tomography (ECT) in biomedical research and patient care. Work during the past year has been augmented by the development and use of an opinion survey instrument to reach a wider representation of knowledgeable investigators and users of this technology. This survey instrument is reproduced in an appendix. Information derived from analysis of the opinion survey, and used in conjunction with results of independent staff studies of available sources, provides the basis for the discussions given in following sections of PET applications in the brain, of technical factors, and of economic implications. Projections of capital and operating costs on a per study basis were obtained from a computerized, pro forma accounting model and are compared with the survey cost estimates for both research and clinical modes of application. The results of a cash-flow model analysis of the relationship between projected economic benefit of PET research to disease management and the costs associated with such research are presented and discussed

  14. The association between heroin expenditure and dopamine transporter availability--a single-photon emission computed tomography study.

    Science.gov (United States)

    Lin, Shih-Hsien; Chen, Kao Chin; Lee, Sheng-Yu; Chiu, Nan Tsing; Lee, I Hui; Chen, Po See; Yeh, Tzung Lieh; Lu, Ru-Band; Chen, Chia-Chieh; Liao, Mei-Hsiu; Yang, Yen Kuang

    2015-03-30

    One of the consequences of heroin dependency is a huge expenditure on drugs. This underlying economic expense may be a grave burden for heroin users and may lead to criminal behavior, which is a huge cost to society. The neuropsychological mechanism related to heroin purchase remains unclear. Based on recent findings and the established dopamine hypothesis of addiction, we speculated that expenditure on heroin and central dopamine activity may be associated. A total of 21 heroin users were enrolled in this study. The annual expenditure on heroin was assessed, and the availability of the dopamine transporter (DAT) was assessed by single-photon emission computed tomography (SPECT) using [(99m)TC]TRODAT-1. Parametric and nonparametric correlation analyses indicated that annual expenditure on heroin was significantly and negatively correlated with the availability of striatal DAT. After adjustment for potential confounders, the predictive power of DAT availability was significant. Striatal dopamine function may be associated with opioid purchasing behavior among heroin users, and the cycle of spiraling dysfunction in the dopamine reward system could play a role in this association. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. The role of positron emission tomography/computed tomography imaging with radiolabeled choline analogues in prostate cancer.

    Science.gov (United States)

    Navarro-Pelayo Láinez, M M; Rodríguez-Fernández, A; Gómez-Río, M; Vázquez-Alonso, F; Cózar-Olmo, J M; Llamas-Elvira, J M

    2014-11-01

    prostate cancer is the most frequent solid malignant tumor in Western Countries. Positron emission tomography/x-ray computed tomography imaging with radiolabeled choline analogues is a useful tool for restaging prostate cancer in patients with rising prostate-specific antigen after radical treatment (in whom conventional imaging techniques have important limitations) as well as in the initial assessment of a selected group of prostate cancer patients. For this reason a literature review is necessary in order to evaluate the usefulness of this imaging test for the diagnosis and treatment of prostate cancer. a MEDLINE (PubMed way) literature search was performed using the search parameters: «Prostate cancer» and «Choline-PET/CT». Other search terms were «Biochemical failure» and/or «Staging» and/or «PSA kinetics». English and Spanish papers were selected; original articles, reviews, systematic reviews and clinical guidelines were included. according to available data, radiolabeled choline analogues plays an important role in the management of prostate cancer, especially in biochemical relapse because technique accuracy is properly correlated with prostate-specific antigen values and kinetics. Although is an emerging diagnostic technique useful in treatment planning of prostate cancer, final recommendations have not been submitted. Copyright © 2013 AEU. Published by Elsevier Espana. All rights reserved.

  16. The Medical Case for a Positron Emission Tomography and X-ray Computed Tomography Combined Service in Oman.

    Science.gov (United States)

    Al-Bulushi, Naima K; Bailey, Dale; Mariani, Giuliano

    2013-11-01

    The value of a positron emission tomography and X-ray computed tomography (PET/CT) combined service in terms of diagnostic accuracy, cost-effectiveness and impact on clinical decision-making is well-documented in the literature. Its role in the management of patients presenting with cancer is shifting from early staging and restaging to the early assessment of the treatment response. Currently, the application of PET/CT has extended to non-oncological specialties-mainly neurology, cardiology and rheumatology. A further emerging application for PET/CT is the imaging of infection/inflammation. This article illustrates some of the PET/CT applications in both oncological and non-oncological disorders. In view of the absence of this modality in Oman, this article aims to increase the awareness of the importance of these imaging modalities and their significant impact on diagnosis and management in both oncological and non-oncological specialties for patients of all age groups as well as the decision-makers.

  17. Seeing the Unseen—Bioturbation in 4D: Tracing Bioirrigation in Marine Sediment Using Positron Emission Tomography and Computed Tomography

    Science.gov (United States)

    Delefosse, Matthieu; Kristensen, Erik; Crunelle, Diane; Braad, Poul Erik; Dam, Johan Hygum; Thisgaard, Helge; Thomassen, Anders; Høilund-Carlsen, Poul Flemming

    2015-01-01

    Understanding spatial and temporal patterns of bioirrigation induced by benthic fauna ventilation is critical given its significance on benthic nutrient exchange and biogeochemistry in coastal ecosystems. The quantification of this process challenges marine scientists because faunal activities and behaviors are concealed in an opaque sediment matrix. Here, we use a hybrid medical imaging technique, positron emission tomography and computed tomography (PET/CT) to provide a qualitative visual and fully quantitative description of bioirrigation in 4D (space and time). As a study case, we present images of porewater advection induced by the well-studied lugworm (Arenicola marina). Our results show that PET/CT allows more comprehensive studies on ventilation and bioirrigation than possible using techniques traditionally applied in marine ecology. We provide a dynamic three-dimensional description of bioirrigation by the lugworm at very high temporal and spatial resolution. Results obtained with the PET/CT are in agreement with literature data on lugworm ventilation and bioirrigation. Major advantages of PET/CT over methods commonly used are its non-invasive and non-destructive approach and its capacity to provide information that otherwise would require multiple methods. Furthermore, PET/CT scan is versatile as it can be used for a variety of benthic macrofauna species and sediment types and it provides information on burrow morphology or animal behavior. The lack of accessibility to the expensive equipment is its major drawback which can only be overcome through collaboration among several institutions. PMID:25837626

  18. [Positron emission tomography combined with computed tomography in the initial evaluation and response assessment in primary central nervous system lymphoma].

    Science.gov (United States)

    Mercadal, Santiago; Cortés-Romera, Montserrat; Vélez, Patricia; Climent, Fina; Gámez, Cristina; González-Barca, Eva

    2015-06-08

    To evaluate the role of positron emission tomography combined with computed tomography (PET-CT) in the initial evaluation and response assessment in primary central nervous system lymphoma (PCNSL). Fourteen patients (8 males) with a median age 59.5 years diagnosed of PCNSL. A brain PET-CT and magnetic resonance imaging (MRI) were performed in the initial evaluation. In 7 patients a PET-CT after treatment was performed. PET-CT showed at diagnosis 31 hypermetabolic focuses and MRI showed 47 lesions, with a good grade of concordance between both (k = 0.61; P = .005). In the response assessment, correlation between both techniques was good, and PET-CT was helpful in the appreciation of residual MRI lesions. Overall survival at 2 years of negative vs. positive PET-CT at the end of treatment was 100 vs. 37.5%, respectively (P = .045). PET-CT can be useful in the initial evaluation of PCNSL, and especially in the assessment of response. Despite the fact that PET-CT detects less small lesions than MRI, a good correlation between MRI and PET-CT was observed. It is effective in the evaluation of residual lesions. Prospective studies are needed to confirm their possible prognostic value. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  19. Diagnostic accuracy of exercise thallium-201 single-photon emission computed tomography in patients with left bundle branch block

    International Nuclear Information System (INIS)

    Larcos, G.; Gibbons, R.J.; Brown, M.L.

    1991-01-01

    Recent reports have proposed that abnormal apical or anterior wall perfusion with exercise thallium-201 imaging may increase diagnostic accuracy for disease of the left anterior descending artery in patients with left bundle branch block (LBBB). To evaluate these suggestions, 83 patients with LBBB who underwent thallium-201 single-photon emission computed tomography and coronary angiography within an interval of 3 months were retrospectively reviewed. There were 59 men and 24 women aged 33 to 84 years (mean 65). Myocardial perfusion to the apex, anterior wall and anterior septum were scored qualitatively by consensus of 2 experienced observers and by quantitative analysis in comparison with a normal data base. The sensitivity, specificity and accuracy of perfusion defects in these segments were then expressed according to angiographic findings. Significant stenosis of vessels within the left anterior descending artery territory was present in 38 patients. By receiver-operator characteristic analysis, a fixed or reversible defect within the apex by the qualitative method was the best criterion for coronary artery disease. However, although highly sensitive (79 and 85% by the qualitative and quantitative methods, respectively), an apical defect was neither specific (38 and 16%, respectively), nor accurate (57 and 46%, respectively). Perfusion abnormalities in the anterior wall and septum were also of limited diagnostic accuracy. Thus, modified interpretative criteria in patients with LBBB are not clinically useful in the assessment of left anterior descending artery disease

  20. Safety of and tolerance to adenosine infusion for myocardial perfusion single-photon emission computed tomography in a Japanese population.

    Science.gov (United States)

    Hatanaka, Kunihiko; Doi, Masayuki; Hirohata, Satoshi; Kamikawa, Shigeshi; Kaji, Yoko; Katoh, Tsutomu; Kusachi, Shozo; Ninomiya, Yoshifumi; Ohe, Tohru

    2007-06-01

    Adenosine has been available for use in myocardial perfusion single-photon emission computed tomography (SPECT) in Japan since 2005. The purpose of this study was to evaluate the safety of and tolerance to thallium-201 myocardial perfusion SPECT with intravenous adenosine infusion in Japanese patients with suspected coronary artery disease. Two hundred and six consecutive patients who underwent an adenosine infusion (120 mug . kg(-1) . min(-1)) SPECT at Sumitomo Besshi Hospital (Niihama, Japan) were investigated. The effects of adenosine infusion were monitored for each patient. A coronary angiography was performed in 81 patients. Adenosine infusion significantly decreased blood pressure and increased heart rate. Adverse reactions were observed in 161 patients (78.2%). Most reactions were transient, disappearing soon after the termination of adenosine infusion. No serious adverse reactions, such as acute myocardial infarction or death, occurred. Adenosine infusion was terminated in 3 patients (1.5%) because of near syncope or sustained 2:1 atrioventricular block. Electrocardiographic changes occurred in 15 patients (7.3%). Self-assessed scoring after SPECT showed that the patients were very tolerant (74.6% of 177 patients) of adenosine infusion myocardial SPECT. The sensitivity and specificity were 75.0% and 69.7%, respectively. Adenosine infusion myocardial SPECT is safe and well tolerated in the Japanese population, despite the frequent occurrence of minor adverse reactions.

  1. Metabolic patterns of the shoulder joint on (18)F-fluorodeoxyglucose positron emission tomography/computed tomography in adhesive capsulitis.

    Science.gov (United States)

    Kim, Du Hwan; Sung, Duk Hyun; Ga, Hyo Yun; Choi, Joon Young

    2014-02-01

    The purpose of our study was to demonstrate metabolic patterns on (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) in patients with adhesive capsulitis (AC). We retrospectively reviewed (18)F-FDG PET/CT performed on 22 shoulders of 21 patients diagnosed with AC: 2 shoulders with stage I, 14 with stage II, and 6 with stage III. A clinical diagnosis of AC was retrospectively made based on clinical examination, clinical course, and imaging. The pattern of radiotracer uptake was analyzed. Standardized uptake values in rotator interval (RI), anterior joint capsule (AJC), axillary recess (AR), and greater tuberosity were measured and compared to those of the contralateral side and the control group consisting of 40 shoulders in 20 subjects without shoulder pain. Four patterns of uptake were noted: (1) glenoid type I (n = 16), with uptake in RI, AJC, and AR; (2) glenoid type II (n = 2),with uptake in AJC and AR; (3) glenoid type III (n = 2), with uptake in RI and AJC; (4) focal type (n = 2), with uptake in RI or AR. Affected side SUVmax for RI, AJC, and AR was significantly higher compared with the unaffected side and the control group. Two shoulders with stage I AC had patterns similar to the ones with stage II or III. Specific patterns of (18)F-FDG uptake with dominant uptake in RI, AJC, or AR may be related to AC.

  2. Imaging pancreas in healthy and diabetic rodent model using [18F]fallypride positron emission tomography/computed tomography.

    Science.gov (United States)

    Garcia, Adriana; Venugopal, Archana; Pan, Min-Liang; Mukherjee, Jogeshwar

    2014-10-01

    A noninvasive method of monitoring the loss of islet cells can provide an earlier and improved diagnosis for therapeutics development of preclinical phases of diabetes. The use of [(18)F]fallypride, a dopamine D2/D3 receptor radiotracer, has been developed as a surrogate marker to evaluate loss of pancreatic islet cells in a rodent model of type 1 diabetes. Healthy Sprague-Dawley rats were administered [(18)F]fallypride and imaged for 2 h in a positron emission tomography (PET)/computed tomography (CT) scan. Diabetes was then induced in the same rats by administration of streptozotocin, and a PET/CT scan was performed 4 days after establishing diabetes. Pancreata of a separate set of rats were evaluated by insulin immunostaining for loss of islet cells by streptozotocin. Blood glucose levels of 125 mg/dL and 550 mg/dL were established for those rats without and with diabetes, respectively. [(18)F]Fallypride uptake in the pancreas of both groups of rats was rapid, but the rats with diabetes showed a significantly lower uptake (less than 50%). The specific binding ratio was decreased by 77% in the diabetic rats. [(18)F]Fallypride can be a useful surrogate marker for monitoring changes in pancreatic islet cells, thus providing a noninvasive method to evaluate efficacy of therapeutics.

  3. A single photon emission computed tomograph based on a limited dumber of detectors for fluid flow visualization

    International Nuclear Information System (INIS)

    Legoupil, S.

    1999-01-01

    We present in this work a method for fluid flow visualization in a system using radioactive tracers. The method is based on single photon emission computed tomography techniques, applied to a limited number of discrete detectors. We propose in this work a method for the estimation of the transport matrix of photons, associated to the acquisition system. This method is based on the modelization of profiles acquired for a set of point sources located in the imaged volume. Monte Carlo simulations allow to separate scattered photons from those directly collected by the system. The influence of the energy tracer is exposed. The reconstruction method is based on the maximum likelihood - expectation maximization algorithm. An experimental device, based on 36 detectors was realised for the visualization of water circulation in a vessel. A video monitoring allows to visualize the dye water tracer. Dye and radioactive tracers are injected simultaneously in a water flow circulating in the vessel. Reconstructed and video images are compared. Quantitative and qualitative analysis show that fluid flow visualization is feasible with a limited number of detectors. This method can be applied for system involving circulations of fluids. (author)

  4. Positron emission tomography-computed tomography in the diagnostic evaluation of smoldering multiple myeloma: identification of patients needing therapy.

    Science.gov (United States)

    Siontis, B; Kumar, S; Dispenzieri, A; Drake, M T; Lacy, M Q; Buadi, F; Dingli, D; Kapoor, P; Gonsalves, W; Gertz, M A; Rajkumar, S V

    2015-10-23

    We studied 188 patients with a suspected smoldering multiple myeloma (MM) who had undergone a positron emission tomography-computed tomography (PET-CT) scan as part of their clinical evaluation. PET-CT was positive (clinical radiologist interpretation of increased bone uptake and/or evidence of lytic bone destruction) in 74 patients and negative in 114 patients. Of these, 25 patients with a positive PET-CT and 97 patients with a negative PET-CT were observed without therapy and formed the study cohort (n=122). The probability of progression to MM within 2 years was 75% in patients with a positive PET-CT observed without therapy compared with 30% in patients with a negative PET-CT; median time to progression was 21 months versus 60 months, respectively, P=0.0008. Of 25 patients with a positive PET-CT, the probability of progression was 87% at 2 years in those with evidence of underlying osteolysis (n=16) and 61% in patients with abnormal PET-CT uptake but no evidence of osteolysis (n=9). Patients with positive PET-CT and evidence of underlying osteolysis have a high risk of progression to MM within 2 years when observed without therapy. These observations support recent changes to imaging requirements in the International Myeloma Working Group updated diagnostic criteria for MM.

  5. The clinical meaning of gastric-wall hyperactivity observed on sestamibi cardiac single-photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Cote, C.; Dumont, M. [Centre Hospitalier Universitaire de Quebec, Dept. of Nuclear Medicine, Quebec, Quebec (Canada)]. E-mail: christian.cote@chuq.qc.ca

    2004-06-01

    To evaluate prospectively the incidence and clinical meaning, if any, of gastric-wall hyperactivity observed on sestamibi cardiac single-photon emission computed tomography (SPECT). This phenomenon is completely different from the well-known intraluminal gastric reflux of sestamibi. A group of 819 patients who underwent sestamibi cardiac SPECT was studied from January 2000 to October 2000. Gastric-wall activity was graded qualitatively. Only patients with gastric-wall activity near or equivalent to their heart activity were considered for subsequent analysis. The medical records of patient candidates were reviewed, and their family physicians were asked to respond to a questionnaire by telephone when further information was needed. We identified 13 patients with significant gastric-wall hyperactivity, which was more intense on rest images. Our review of the clinical data shows that all these patients were suffering from dyspepsia and were taking gastric medication. These 13 cases were assigned to 3 groups: gastroesophageal reflux, chronic functional dyspepsia and nonspecific gastritis. Significant gastric-wall hyperactivity is an infrequent observation on sestamibi cardiac SPECT. Our results indicate that the presence of significant gastric-wall hyperactivity is associated with dyspepsia. It is important to realize that this gastric-wall hyperactivity by its proximity to the inferior myocardial wall could in some circumstances lead to either false-negative or false-positive findings, representing a diagnostic problem. Although infrequent, this situation could be avoided by proper quality control, including a systematic review of the raw cine data before reading the images. (author)

  6. A computed tomography-based spatial normalization for the analysis of [18F] fluorodeoxyglucose positron emission tomography of the brain.

    Science.gov (United States)

    Cho, Hanna; Kim, Jin Su; Choi, Jae Yong; Ryu, Young Hoon; Lyoo, Chul Hyoung

    2014-01-01

    We developed a new computed tomography (CT)-based spatial normalization method and CT template to demonstrate its usefulness in spatial normalization of positron emission tomography (PET) images with [(18)F] fluorodeoxyglucose (FDG) PET studies in healthy controls. Seventy healthy controls underwent brain CT scan (120 KeV, 180 mAs, and 3 mm of thickness) and [(18)F] FDG PET scans using a PET/CT scanner. T1-weighted magnetic resonance (MR) images were acquired for all subjects. By averaging skull-stripped and spatially-normalized MR and CT images, we created skull-stripped MR and CT templates for spatial normalization. The skull-stripped MR and CT images were spatially normalized to each structural template. PET images were spatially normalized by applying spatial transformation parameters to normalize skull-stripped MR and CT images. A conventional perfusion PET template was used for PET-based spatial normalization. Regional standardized uptake values (SUV) measured by overlaying the template volume of interest (VOI) were compared to those measured with FreeSurfer-generated VOI (FSVOI). All three spatial normalization methods underestimated regional SUV values by 0.3-20% compared to those measured with FSVOI. The CT-based method showed slightly greater underestimation bias. Regional SUV values derived from all three spatial normalization methods were correlated significantly (p brain regions or highly variable within study population.

  7. Thallium-201 single photon emission computed tomography (SPECT) in patients with Duchenne's progressive muscular dystrophy. A histopathologic correlation study

    International Nuclear Information System (INIS)

    Nishimura, Toru; Yanagisawa, Atsuo; Sakata, Konomi; Shimoyama, Katsuya; Yoshino, Hideaki; Ishikawa, Kyozo; Sakata, Hitomi; Ishihara, Tadayuki

    2001-01-01

    The pathomorphologic mechanism responsible for abnormal perfusion imaging during thallium-201 myocardial single photon emission computed tomography ( 201 Tl-SPECT) in patients with Duchenne's progressive muscular dystrophy (DMD) was investigated. Hearts from 7 patients with DMD were evaluated histopathologically at autopsy and the results correlated with findings on initial and delayed resting 201 Tl-SPECT images. The location of segments with perfusion defects correlated with the histopathologically abnormal segments in the hearts. Both the extent and degree of myocardial fibrosis were severe, especially in the posterolateral segment of the left ventricle. Severe transmural fibrosis and severe fatty infiltration were common in segments with perfusion defects. In areas of redistribution, the degree of fibrosis appeared to be greater than in areas of normal perfusion; and intermuscular edema was prominent. Thus, the degree and extent of perfusion defects detected by 201 Tl-SPECT were compatible with the histopathology. The presence of the redistribution phenomenon may indicate ongoing fibrosis. Initial and delayed resting 201 Tl-SPECT images can predict the site and progress of myocardial degeneration in patients with DMD. (author)

  8. Usefulness of single photon emission computed tomography imaging in the detection of lumbar vertebral metastases from prostate cancer

    International Nuclear Information System (INIS)

    Nozaki, Tetsuo; Yasuda, Kenji; Akashi, Takuya; Fuse, Hideki

    2008-01-01

    To determine whether single photon emission computed tomography (SPECT) is useful in the detection of prostate cancer bone metastases in the lumbar vertebrae. Thirty-nine patients (12 with benign prostatic hyperplasia, 27 with prostate cancer) were considered and submitted to bone SPECT. All of them had increased uptake in lumbar vertebrae on bone scintigraphy. In those with prostate cancer, definitive diagnosis of bone metastases was established by magnetic resonance imaging (MRI). SPECT axial images were classified into five accumulation patterns: mosaic, large hot, diffuse, peripheral, and articular (or pediculate). Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of bone SPECT were calculated. Overall, 116 vertebral lesions (49 metastatic, 67 degenerative) were studied. Mosaic, large hot and diffuse patterns were more frequently associated with metastatic lesions (84.2%, 70.3%, and 63.1% of the cases, respectively). On the other hand, peripheral and articular (or pediculate) patterns were mostly ascribed to degenerative lesions (100% and 87.5% of the cases, respectively). Sensitivity, specificity, PPV and NPV of bone SPECT were 95.9% (47/49), 73.1% (49/67), 72.3% (47/65), and 96.1% (49/51), respectively. Bone SPECT provides better accuracy than bone scintigraphy in differential diagnosis of lumbar vertebral lesions from prostate cancer. (author)

  9. Single photon emission computed tomography and statistical parametric mapping analysis in cirrhotic patients with and without minimal hepatic encephalopathy

    International Nuclear Information System (INIS)

    Nakagawa, Yuri; Matsumura, Kaname; Iwasa, Motoh; Kaito, Masahiko; Adachi, Yukihiko; Takeda, Kan

    2004-01-01

    The early diagnosis and treatment of cognitive impairment in cirrhotic patients is needed to improve the patients' daily living. In this study, alterations of regional cerebral blood flow (rCBF) were evaluated in cirrhotic patients using statistical parametric mapping (SPM). The relationships between rCBF and neuropsychological test, severity of disease and biochemical data were also assessed. 99m Tc-ethyl cysteinate dimer single photon emission computed tomography was performed in 20 patients with non-alcoholic liver cirrhosis without overt hepatic encephalopathy (HE) and in 20 age-matched healthy subjects. Neuropsychological tests were performed in 16 patients; of these 7 had minimal HE. Regional CBF images were also analyzed in these groups using SPM. On SPM analysis, cirrhotic patients showed regions of significant hypoperfusion in the superior and middle frontal gyri, and inferior parietal lobules compared with the control group. These areas included parts of the premotor and parietal associated areas of the cortex. Among the cirrhotic patients, those with minimal HE had regions of significant hypoperfusion in the cingulate gyri bilaterally as compared with those without minimal HE. Abnormal function in the above regions may account for the relatively selective neuropsychological deficits in the cognitive status of patients with cirrhosis. These findings may be important in the identification and management of cirrhotic patients with minimal HE. (author)

  10. Corrected coronary opacification decrease from coronary computed tomography angiography: Validation with quantitative 13N-ammonia positron emission tomography.

    Science.gov (United States)

    Benz, Dominik C; Gräni, Christoph; Ferro, Paola; Neumeier, Luis; Messerli, Michael; Possner, Mathias; Clerc, Olivier F; Gebhard, Catherine; Gaemperli, Oliver; Pazhenkottil, Aju P; Kaufmann, Philipp A; Buechel, Ronny R

    2017-07-06

    To assess the functional relevance of a coronary artery stenosis, corrected coronary opacification (CCO) decrease derived from coronary computed tomography angiography (CCTA) has been proposed. The present study aims at validating CCO decrease with quantitative 13N-ammonia positron emission tomography (PET) myocardial perfusion imaging (MPI). This retrospective study consists of 39 patients who underwent hybrid CCTA/PET-MPI. From CCTA, attenuation in the coronary lumen was measured before and after a stenosis and corrected to the aorta to calculate CCO and its decrease. Relative flow reserve (RFR) was calculated by dividing the stress myocardial blood flow (MBF) of a vessel territory subtended by a stenotic coronary by the stress MBF of the reference territories without stenoses. RFR was abnormal in 11 vessel territories (27%). CCO decrease yielded a sensitivity, specificity, negative predictive value, positive predictive value, and accuracy for prediction of an abnormal RFR of 73%, 70%, 88%, 47%, and 70%, respectively. CCTA-derived CCO decrease has moderate diagnostic accuracy to predict an abnormal RFR in PET-MPI. However, its high negative predictive value to rule out functional relevance of a given lesion may confer clinical implications in the diagnostic work-up of patients with a coronary stenosis.

  11. Single photon emission computed tomography before and after treatment of anxiety using a selective serotonin reuptake inhibitor

    International Nuclear Information System (INIS)

    Warwick, J.M.; Heerden, B.B. van; Stein, D.J.; Niehaus, D.J.H.; Seedat, S.; Linden, G. van der; Harvey, B.A.

    2002-01-01

    Background: The selective serotonin reuptake inhibitors (SSRIs) are currently recommended as first line medications for a number of different anxiety disorders, including obsessive-compulsive disorder (OCD), posttraumatic stress disorder (PTSD), and social anxiety disorder (social phobia) (SAD). This raises the question of what effects these agents have on the functional neuroanatomy of anxiety disorders. Methods: Single photon emission computed tomography (SPECT) brain scanning was undertaken in patients with OCD, PTSD, and SAD before and after treatment with citalopram, the most selective of the SSRIs. Statistical parametric mapping (SPM) was used to compare scans (pre- vs post-medication, and responders vs nonresponders) in the combined group of subjects. Results: Citalopram pharmacotherapy resulted in significant deactivation within anterior and superior cingulate and left hippocampus. Deactivation within the anterior cingulate, left paracingular cortex, and right inferior frontal cortex was more marked in treatment responders. Baseline activation did not, however, predict response to pharmacotherapy. Conclusion: Although each of the anxiety disorders may be mediated by different neurocircuits, there are some overlaps in the functional neuroanatomy of their response to SSRI treatment. The current data is consistent with previous work demonstrating the importance of limbic circuits in this spectrum of disorders. These play a crucial role in cognitive-affective processing, and are innervated by serotonergic neurons

  12. Clinico-radiological correlation of Wilson's disease by magnetic resonance imaging, computed tomography and positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Ken; Sakata, Chigusa; Nemoto, Hiroshi; Yokoi, Fuji; Sunohara, Nobuhiko (National Center of Neurology and Psychiatry, Kodaira, Tokyo (Japan)); Iio, Masaaki

    1991-02-01

    Five patients with Wilson's disease received repeated magnetic resonance imaging (MRI) and computed tomography (CT) examinations at intervals from 6 to 29 months. Four patients, except for asymptomatic one, also underwent positron emission tomography (PET). The significance and limitations of these imaging modalities were examined in the light of their correlation with clinical manifestations and their therapeutic evaluation. The following focal regions, detected on MRI, had a strong positive correlation with clinical manifestations: the lenticular nuclei for dystonia, the brain stem for abnormality of smooth persuit eye movements, and the caudate and lenticular nuclei for severe dysarthria/dysphagia. Follow-up MRI for 3 patients showed an improvement of findings in the lenticular nuclei, lateral part of the putamen, and brain stem, that was in accordance with improved clinical or neurologic manifestations, such as dystonia and cerebellar symptoms. Severe abnormality in the caudate nucleus was associated with poor prognosis. Repeated CT failed to show serial changes in any of the patients. Regional blood flow and oxygen metabolic rate, obtained by PET examinations, were slightly decreased in the thalamus that had normal findings on both MRI and CT, as well as in the cerebral cortex and basal ganglia. PET was, however, inferior to MRI in detecting fine foci within the basal ganglia. In conclusion, there was a good correlation between MRI findings, particularly foci of the caudate and lenticular nuclei, and clinical manifestations. Repeated MRI examinations were the most useful approach to the evaluation of therapeutic effects and prognosis. (N.K.).

  13. Real-time axial motion detection and correction for single photon emission computed tomography using a linear prediction filter

    International Nuclear Information System (INIS)

    Saba, V.; Setayeshi, S.; Ghannadi-Maragheh, M.

    2011-01-01

    We have developed an algorithm for real-time detection and complete correction of the patient motion effects during single photon emission computed tomography. The algorithm is based on a linear prediction filter (LPC). The new prediction of projection data algorithm (PPDA) detects most motions-such as those of the head, legs, and hands-using comparison of the predicted and measured frame data. When the data acquisition for a specific frame is completed, the accuracy of the acquired data is evaluated by the PPDA. If patient motion is detected, the scanning procedure is stopped. After the patient rests in his or her true position, data acquisition is repeated only for the corrupted frame and the scanning procedure is continued. Various experimental data were used to validate the motion detection algorithm; on the whole, the proposed method was tested with approximately 100 test cases. The PPDA shows promising results. Using the PPDA enables us to prevent the scanner from collecting disturbed data during the scan and replaces them with motion-free data by real-time rescanning for the corrupted frames. As a result, the effects of patient motion is corrected in real time. (author)

  14. Detection of occult thymoma during exercise thallium 201, technetium 99m tetrofosmin imaging for coronary artery disease.

    Science.gov (United States)

    Paull, D E; Graham, J; Forgetta, J; Turissini, T; Saidman, B

    2000-08-01

    Thallium (Tl) 201 and technetium (Tc) 99m tetrofosmin single-photon emission CT are routinely used in the evaluation of coronary artery disease. Mediastinal tumors demonstrate Tl 201 and Tc 99m tetrofosmin uptake. We report a 56-year-old man who developed chest pain after a previously successful angioplasty and stent of the left anterior descending coronary artery. He underwent a Tl 201, Tc 99m tetrofosmin exercise study. Abnormal mediastinal activity was visualized in both the Tl 201 and Tc 99m tetrofosmin images. Subsequently, the patient underwent resection of a stage II thymoma. Unanticipated focal extracardiac accumulation during myocardial scintiscanning should lead to further investigation to exclude mediastinal tumor.

  15. COMPUTING

    CERN Document Server

    M. Kasemann

    Overview In autumn the main focus was to process and handle CRAFT data and to perform the Summer08 MC production. The operational aspects were well covered by regular Computing Shifts, experts on duty and Computing Run Coordination. At the Computing Resource Board (CRB) in October a model to account for service work at Tier 2s was approved. The computing resources for 2009 were reviewed for presentation at the C-RRB. The quarterly resource monitoring is continuing. Facilities/Infrastructure operations Operations during CRAFT data taking ran fine. This proved to be a very valuable experience for T0 workflows and operations. The transfers of custodial data to most T1s went smoothly. A first round of reprocessing started at the Tier-1 centers end of November; it will take about two weeks. The Computing Shifts procedure was tested full scale during this period and proved to be very efficient: 30 Computing Shifts Persons (CSP) and 10 Computing Resources Coordinators (CRC). The shift program for the shut down w...

  16. Vestibularis-schwannomers diagnostik og vaekst bedømt ved SPECT kombineret med TL-201 Thallium

    DEFF Research Database (Denmark)

    Charabi, S; Lassen, N A; Jacobsen, G K

    1999-01-01

    The value of SPECT scanning in diagnosis and growth potential of vestibular schwannoma (VS) was investigated in a series of 29 patients. SPECT demonstrated all tumours > 0.8 cm3, but had limitations as a diagnostic modality of small intracanalicular tumours, when compared to gadolinium DTPA enhan...

  17. Agreement of left ventricular ejection fraction and volumes between adenosine stress TL-201 gated SPECT and echocardiography

    Energy Technology Data Exchange (ETDEWEB)

    Pai, M. S. [College of Medicine, Univ. of Ewha, Seoul (Korea, Republic of); Moon, D. H.; Kim, H. M.; Yang, Y. J.; Kang, D. H. [Asan Medical Center, Seoul (Korea, Republic of)

    2003-07-01

    Electrocardiogram-gated TI-201 SPECT measurements of left ventricular ejection fraction (EF), end-diastolic volume (EDV), and end-systolic volume (ESV) have shown high correlation with conventional methods. However, how much these parameters measured by TI-201 gated SPECT differ from those by echocardiography has not been assessed. Adenosine stress (Ad-G) and redistribution TI-201 gated SPECT (Re-G) and resting echocardiography were conducted in 337 patients (184 male, 153 female). EDV, ESV and LVEF measured by QGS software were compared with the results by echocardiography. Patients with arrhythmia (atrial fibrillation or frequent premature contractions) or evidence of fixed or reversible perfusion defects on TI-201 SPECT were excluded. EF, EDV and ESV measured by Ad-G (63.3{+-}9.8,73.8{+-}30.2,29.1{+-}20.1) and Re-G (65.2{+-}11.6,69.1{+-}30.1,26.5{+-}20.3) correlated well with those by Echo (61.4{+-}7.9,78.3{+-}2.7, 30.7{+-} 17.5 ; r of Ad-G=0.547, 0.850, 0.827, p<0.001 ; r of Re-G=0.585, 0.838, 0.819, p<0.001). However the difference (mean, SD, SEE of Echo - gated SPECT) was statistically significant (EF: Ad-G=1.71, 8.92, 0.48, Re-G=3.59, 10.39, 0.56, p<0.001 ; EDV: Ad-G=4.75, 16.21, 0.88, Re-G=9.53, 16.77, 0.91, p<0.001 ; ESV: Ad-G=1.75, 11.35, 0.61, p<0.05, Re-G=4.29, 11.7, 0.63, p<0.001). Bland-Altman plots showed that the difference of EDV and ESV did not vary in any systematic way over the range of measurement, whereas the difference of EF increased with increasing average EF by Echo and gated-SPECT. The difference of EF, EDV, and ESV between Ad-G and Echo was significantly smaller than those between Re-G and Echo (p<0.001). Gated TI-201 SPECT underestimates EDV and ESV over a wide range of volume. As a result, EF by gated TI-201 SPECT is overestimated especially in patients with small LV volume. Ad-G is preferable to Re-G in assessing left ventricular ejection fraction and volume in place of Echo because of smaller bias.

  18. The effects of chemical and radioactive properties of Tl-201 on human erythrocyte glucose 6-phosphate dehydrogenase activity

    International Nuclear Information System (INIS)

    Sahin, Ali; Senturk, Murat; Ciftci, Mehmet; Varoglu, Erhan; Kufrevioglu, Omer Irfan

    2010-01-01

    Aim: The inhibitory effects of thallium-201 ( 201 Tl) solution on human erythrocyte glucose 6-phosphate dehydrogenase (G6PD) activity were investigated. Methods: For this purpose, erythrocyte G6PD was initially purified 835-fold at a yield of 41.7% using 2',5'-Adenosine diphosphate sepharose 4B affinity gel chromatography. The purification was monitored by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, which showed a single band for the final enzyme preparation. The in vitro and in vivo effects of the 201 Tl solution including Tl + , Fe +3 and Cu +2 metals and the in vitro effects of the radiation effect of the 201 Tl solution and non-radioactive Tl + , Fe +3 and Cu +2 metals on human erythrocyte G6PD enzyme were studied. Enzyme activity was determined with the Beutler method at 340 nm using a spectrophotometer. All purification procedures were carried out at +4 deg. C. Results: 201 Tl solution and radiation exposure had inhibitory effects on the enzyme activity. IC 50 value of 201 Tl solution was 36.86 μl ([Tl + ]: 0.0036 μM, [Cu +2 ]: 0.0116 μM, [Fe +3 ]: 0.0132 μM), of human erythrocytes G6PD. Seven human patients were also used for in vivo studies of 201 Tl solution. Furthermore, non-radioactive Tl + , Fe +3 and Cu +2 were found not to have influenced the enzyme in vitro. Conclusion: Human erythrocyte G6PD activity was inhibited by exposure for up to 10 minutes to 0.057 mCi/kg 201 Tl solution. It was detected in in vitro and in vivo studies that the human erythrocyte G6PD enzyme is inhibited due to the radiation effect of 201 Tl solution.

  19. Emissive computed tomography

    International Nuclear Information System (INIS)

    Franke, R.; Schoeppy, H.; Gambini, M.R.; Martone, R.J.; Kearns, D.S.; Enos, G.W.

    1987-01-01

    A medical diagnostic mechanism is described comprising: (a) an elongated structure defining a gantry travel path; (b) a gantry mounted on the structure for movement along the path of travel; (c) drive means connected to the gantry for driving the gantry along its path of travel; (d) a nuclear camera detector orbitally mounted on the gantry and positionable spaced from the gantry and proximate a patient for conducting nuclear medical diagnostic studies, and (e) means for facilitating rotation of at least a portion of the gantry and of the detector about an axis transverse to the travel path

  20. COMPUTING

    CERN Multimedia

    I. Fisk

    2011-01-01

    Introduction CMS distributed computing system performed well during the 2011 start-up. The events in 2011 have more pile-up and are more complex than last year; this results in longer reconstruction times and harder events to simulate. Significant increases in computing capacity were delivered in April for all computing tiers, and the utilisation and load is close to the planning predictions. All computing centre tiers performed their expected functionalities. Heavy-Ion Programme The CMS Heavy-Ion Programme had a very strong showing at the Quark Matter conference. A large number of analyses were shown. The dedicated heavy-ion reconstruction facility at the Vanderbilt Tier-2 is still involved in some commissioning activities, but is available for processing and analysis. Facilities and Infrastructure Operations Facility and Infrastructure operations have been active with operations and several important deployment tasks. Facilities participated in the testing and deployment of WMAgent and WorkQueue+Request...

  1. COMPUTING

    CERN Multimedia

    M. Kasemann

    Overview During the past three months activities were focused on data operations, testing and re-enforcing shift and operational procedures for data production and transfer, MC production and on user support. Planning of the computing resources in view of the new LHC calendar in ongoing. Two new task forces were created for supporting the integration work: Site Commissioning, which develops tools helping distributed sites to monitor job and data workflows, and Analysis Support, collecting the user experience and feedback during analysis activities and developing tools to increase efficiency. The development plan for DMWM for 2009/2011 was developed at the beginning of the year, based on the requirements from the Physics, Computing and Offline groups (see Offline section). The Computing management meeting at FermiLab on February 19th and 20th was an excellent opportunity discussing the impact and for addressing issues and solutions to the main challenges facing CMS computing. The lack of manpower is particul...

  2. COMPUTING

    CERN Multimedia

    P. McBride

    The Computing Project is preparing for a busy year where the primary emphasis of the project moves towards steady operations. Following the very successful completion of Computing Software and Analysis challenge, CSA06, last fall, we have reorganized and established four groups in computing area: Commissioning, User Support, Facility/Infrastructure Operations and Data Operations. These groups work closely together with groups from the Offline Project in planning for data processing and operations. Monte Carlo production has continued since CSA06, with about 30M events produced each month to be used for HLT studies and physics validation. Monte Carlo production will continue throughout the year in the preparation of large samples for physics and detector studies ramping to 50 M events/month for CSA07. Commissioning of the full CMS computing system is a major goal for 2007. Site monitoring is an important commissioning component and work is ongoing to devise CMS specific tests to be included in Service Availa...

  3. Multimodal imaging analysis of single-photon emission computed tomography and magnetic resonance tomography for improving diagnosis of Parkinson's disease

    International Nuclear Information System (INIS)

    Barthel, H.; Georgi, P.; Slomka, P.; Dannenberg, C.; Kahn, T.

    2000-01-01

    Parkinson's disease (PD) is characterized by a degeneration of nigrostriated dopaminergic neurons, which can be imaged with 123 I-labeled 2β-carbomethoxy-3β-(4-iodophenyl) tropane ([ 123 I]β-CIT) and single-photon emission computed tomography (SPECT). However, the quality of the region of interest (ROI) technique used for quantitative analysis of SPECT data is compromised by limited anatomical information in the images. We investigated whether the diagnosis of PD can be improved by combining the use of SPECT images with morphological image data from magnetic resonance imaging (MRI)/computed tomography (CT). We examined 27 patients (8 men, 19 women; aged 55±13 years) with PD (Hoehn and Yahr stage 2.1±0.8) by high-resolution [ 123 I]β-CIT SPECT (185-200 MBq, Ceraspect camera). SPECT images were analyzed both by a unimodal technique (ROIs defined directly within the SPECT studies) and a multimodal technique (ROIs defined within individual MRI/CT studies and transferred to the corresponding interactively coregistered SPECT studies). [ 123 I]β-CIT binding ratios (cerebellum as reference), which were obtained for heads of caudate nuclei (CA), putamina (PU), and global striatal structures were compared with clinical parameters. Differences between contra- and ipsilateral (related to symptom dominance) striatal [ 123 I]β-CIT binding ratios proved to be larger in the multimodal ROI technique than in the unimodal approach (e.g., for PU: 1.2*** vs. 0.7**). Binding ratios obtained by the unimodal ROI technique were significantly correlated with those of the multimodal technique (e.g., for CA: y=0.97x+2.8; r=0.70; P com subscore (r=-0.49* vs. -0.32). These results show that the impact of [ 123 I]β-CIT SPECT for diagnosing PD is affected by the method used to analyze the SPECT images. The described multimodal approach, which is based on coregistration of SPECT and morphological imaging data, leads to improved determination of the degree of this dopaminergic disorder

  4. Prediction of Cognitive Decline from White Matter Hyperintensity and Single-Photon Emission Computed Tomography in Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Ken-ichi Tabei

    2017-09-01

    Full Text Available BackgroundWhile several studies support an association of white matter hyperintensity (WMH volume and regional cerebral blood flow (rCBF with cognitive decline in Alzheimer’s disease (AD, no reports have simultaneously considered the effects of both factors on cognitive decline.ObjectiveThe purpose of the present study was to compare WMH volume and rCBF in relation to cognitive function by developing a new software program to fuse magnetic resonance imaging (MRI and single-photon emission computed tomography (SPECT data.MethodWe used MRI, SPECT, and neuropsychological data from 182 serial outpatients treated at the memory clinic of our hospital.ResultsTwenty-nine AD patients fulfilled the inclusion criteria (18 females, mean age: 73.1 ± 7.9 years, mean Mini-Mental State Examination: 23.1 ± 3.0. Analysis of variance revealed that posterior deep WMH (DWMH volume was significantly larger than both anterior periventricular hyperintensity (PVH and DWMH, and posterior PVH volumes. Multivariate regression analysis showed that increased volumes of the anterior PVH and the posterior DWMH and decreased rCBF of the parietal cortex negatively affected cognitive function. The other areas had no significant negative effects on cognitive function.ConclusionOur findings show that the volume of the posterior WMH was significantly larger than that of other areas, and the increased posterior WMH volume and decreased rCBF of the parietal cortex negatively affected cognitive function. Therefore, the posterior WMH volume and the parietal rCBF are key parameters of cognitive decline in AD patients.

  5. Application of positron emission tomography-computed tomography in the diagnosis of pulmonary ground-glass nodules.

    Science.gov (United States)

    Hu, Lili; Pan, Yuanwei; Zhou, Zhigang; Gao, Jianbo

    2017-11-01

    The aim of the present study was to investigate the value of positron emission tomography-computed tomography (PET-CT) using 18 F-fluorodeoxyglucose in the clinical diagnosis of pulmonary ground-glass nodule. In total, 54 patients with pulmonary GGN that were identified by PET-CT examination were selected and confirmed by pathology and clinical diagnosis in hospital between April 2014 and April 2015. The association between PET-CT findings and pathology, and the value of PET-CT were then evaluated. In the 54 patients, solitary pulmonary GGN with a nodule diameter of between 0.6 and 2.0 cm were detected. Amongst them, the PET-CT examination of 42 patients revealed hyper metabolic nodules, and were all mixed GGN type nodules with a diameter >1 cm. The PET-CT examination of the remaining 12 patients demonstrated no evidence of metabolic abnormalities and the nodules in these patients were pure or mixed GGN with a diameter <1 cm (except 2 cases with a diameter ≥1 cm). Furthermore, the diagnoses for all patients were pathologically confirmed by CT-guided needle biopsy or thoracoscopic surgical resection. Amongst them, there were 41 cases of lung adenocarcinoma, 4 cases of fungal infection, 7 cases of inflammation and 2 cases of adenomatoid hyperplasia. Additionally, PET-CT has a lower detection rate for smaller GGN exhibits no clear advantage for pure GGN, but has a higher detection rate for larger GGN. In conclusion, to a certain extent, PET-CT makes up for the shortcomings of traditional imaging and has some clinical value for the diagnosis of GGN.

  6. Standardized uptake value on positron emission tomography/computed tomography predicts prognosis in patients with locally advanced pancreatic cancer.

    Science.gov (United States)

    Wang, Si-Liang; Cao, Shuo; Sun, Yu-Nan; Wu, Rong; Chi, Feng; Tang, Mei-Yue; Jin, Xue-Ying; Chen, Xiao-Dong

    2015-10-01

    The aim of the present study was to investigate the use and value of maximum standardized uptake value (SUV max) on positron emission tomography/computed tomography (PET/CT) images as a prognostic marker for patients with locally advanced pancreatic cancer (LAPC). The medical records of all consecutive patients who underwent PET/CT examination in our institution were retrospectively reviewed. Inclusion criteria were histologically or cytologically proven LAPC. Patients with distant metastasis were excluded. For statistical analysis, the SUV max of primary pancreatic cancer was measured. Survival rates were calculated using the Kaplan-Meier method, and multivariable analysis was performed to determine the association of SUV max with overall survival (OS) and progression-free survival (PFS) using a Cox proportional hazards model. Between July 2006 and June 2013, 69 patients were enrolled in the present study. OS and PFS were 14.9 months [95% confidence interval (CI) 13.1-16.7] and 8.3 months (95% CI 7.1-9.5), respectively. A high SUV max (>5.5) was observed in 35 patients, who had significantly worse OS and PFS than the remaining patients with a low SUV max (P = 0.025 and P = 0.003). Univariate analysis showed that SUV max and tumor size were prognostic factors for OS, with a hazard ratio of 1.90 and 1.81, respectively. A high SUV max was an independent prognostic factor, with a hazard ratio of 1.89 (95% CI 1.015-3.519, P = 0.045). The present study suggests that increased SUV max is a predictor of poor prognosis in patients with LAPC.

  7. Diagnostic accuracy of (18) F-methylcholine positron emission tomography/computed tomography for intra- and extrahepatic hepatocellular carcinoma.

    Science.gov (United States)

    Bieze, Matthanja; Klümpen, Heinz-Josef; Verheij, Joanne; Beuers, Ulrich; Phoa, Saffire S K S; van Gulik, Thomas M; Bennink, Roelof J

    2014-03-01

    Diagnosis of hepatocellular carcinoma (HCC) primarily involves imaging. The aim of this study was to assess the accuracy of (18) F-fluorocholine ((18) F-FCH) positron emission tomography (PET) for detection of HCC and evaluation of extent of disease. Patients with HCC >1 cm were included between 2009 and July 2011, and follow-up closed in February 2013. Diagnosis was based on American Association for the Study of Liver Diseases criteria, and all patients underwent (18) F-FCH PET/computed tomography (CT) at baseline before treatment, 6 underwent a second PET/CT posttreatment, and 1 a third during follow-up. Whole-body PET and low-dose CT imaging were performed 15 minutes after (18) F-FCH injection. Evaluation of imaging was done with standardized uptake value (SUV) ratios: SUV maximum of the lesion divided by the SUV mean of surrounding tissue. Statistical analyses included descriptive analyses, receiver operating characteristic curve, McNemar's test, and Kaplan-Meier's test at 5% level of significance. Twenty-nine patients revealed 53 intrahepatic lesions. In 48 of 53 lesions, (18) F-FCH PET was positive (SUVratio , 1.95 ± 0.66; sensitivity, 88%; specificity, 100%). PET/CT showed uptake in 18 extrahepatic lesions and no uptake in 3 lesions affirmed non-HCC lesions; all lesions were confirmed with additional investigation (accuracy, 100%). In 17 of 29 patients, additional lesions were found on PET/CT imaging, with implications for treatment in 15 patients. Posttreatment PET/CT showed identical results, compared with standard treatment evaluation. This study shows additional value of (18) F-FCH PET/CT for patients with HCC. (18) F-FCH PET/CT has implications for staging, management, and treatment evaluation because of accurate assessment of extrahepatic disease. © 2014 by the American Association for the Study of Liver Diseases.

  8. Differences in fluorodeoxyglucose positron emission tomography/computed tomography findings between elderly onset rheumatoid arthritis and polymyalgia rheumatica.

    Science.gov (United States)

    Takahashi, Hiroyuki; Yamashita, Hiroyuki; Kubota, Kazuo; Miyata, Yoko; Okasaki, Momoko; Morooka, Miyako; Takahashi, Yuko; Kaneko, Hiroshi; Kano, Toshikazu; Mimori, Akio

    2015-07-01

    To compare the fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) findings in patients with elderly-onset rheumatoid arthritis (EORA) with those in patients with polymyalgia rheumatica (PMR), two conditions with similar clinical presentations. We retrospectively analyzed the FDG-PET/CT findings in 10 patients with EORA and 27 patients with PMR admitted to our department between 2006 and 2012. No significant difference was observed in the median patient ages at the time of FDG-PET/CT scans in the EORA and PMR groups (73.5 vs. 78.0 years, respectively). Significant differences in both FDG uptake scores and standardized uptake values were observed between the two groups in the ischial tuberosities, spinous processes, and wrists. No significant differences were detected in the shoulders and hips. However, specific uptake patterns were observed in each group: circular and linear uptake patterns were observed around the humeral head in the EORA group, whereas focal and non-linear uptake patterns were observed in the PMR group. Moreover, focal uptake in front of the hip joint, indicating iliopectineal bursitis, tended to be limited to the PMR group. High sensitivity (92.6%) and specificity (90%) were observed for PMR diagnoses when at least three of the following five items were satisfied: characteristic findings of shoulder and iliopectineal bursitis, FDG uptake in ischial tuberosities and spinal spinous processes, and lack of FDG uptake in the wrists. The differences in the degree of uptake at each lesion and in uptake patterns at the shoulders and hips are potentially useful for obtaining a definitive diagnosis.

  9. (18)F-FDG positron-emission tomography/computed tomography findings of radiographic lesions suggesting old healed tuberculosis.

    Science.gov (United States)

    Jeong, Yun-Jeong; Paeng, Jin Chul; Nam, Hyun-Yeol; Lee, Ji Sun; Lee, Sang-Min; Yoo, Chul-Gyu; Kim, Young Whan; Han, Sung Koo; Yim, Jae-Joon

    2014-03-01

    The presence of radiographic lesions suggesting old healed tuberculosis (TB) is one of the strongest risk factors for the subsequent development of active TB. We elucidated the metabolic activity of radiographic lesions suggesting old healed TB using (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT). This cross-sectional study included 63 participants with radiographic lesions suggesting old healed TB and with available (18)F-FDG PET/CT scans. The maximum standardized uptake value (SUVmax) measured in the lesions, the clinical characteristics, results of the tuberculin skin test (TST) and interferon-γ release assay (IGRA) were analyzed. The SUVmax in old healed TB was 1.5 or higher among nine (14.3%) participants. Age (adjusted odds ratio [aOR], 1.23; 95% CI, 1.03-1.46), history of previous TB (aOR, 60.43; 95% CI, 1.71-2131.65), and extent of the lesions (aOR, 1.34; 95% CI, 1.02-1.75) were associated with higher SUVmax. The positive rates for the TST and IGRA were not different between groups with and without increased FDG uptake. Increased FDG uptake on (18)F-FDG PET/CT was observed in a subset of patients with radiographic lesions suggesting old healed TB. Given that the factors associated with increased FDG uptake are known risk factors for TB development, the possibility exists that participants with old healed TB lesions with higher SUV on (18)F-FDG PET/CT scans might be at higher risk for active TB.

  10. Whole-body positron emission tomography using fluorodeoxyglucose for staging of lymphoma: effectiveness and comparison with computed tomography

    International Nuclear Information System (INIS)

    Stumpe, K.D.M.; Urbinelli, M.; Steinert, H.C.; Glanzmann, C.; Buck, A.; Schulthess, G.K. von

    1998-01-01

    The purpose of this study was to evaluate whole-body positron emission tomography (WB-PET) as a staging modality in Hodgkin's disease (HD) and non-Hodgkin lymphoma (NHL) and to compare it with computed tomography (CT) in a retrospective study. Seventy-one WB-PET studies using fluorodeoxyglucose (FDG) and 49 CT examinations were performed in 19 women and 31 men. Transaxial images were acquired and reformatted coronally and sagittally in PET. CT sections were obtained from the skull base to the pelvic floor. The written reports of the imaging data were compared with a reference standard constructed on the basis of all the data on the individual patients, including clinical follow-up of at least 6 months. The sensitivity and specificity of PET were, respectively, 86% and 96% for HD (n=53), and 89% and 100% for NHL (n=18). For CT sensitivity and specificity were 81% and 41% for HD (n=33) and 86% and 67% for NHL (n=16). Differences between PET and CT sensitivities were not significant, while in HD there was a significant difference in the specificity of PET and CT examinations, mainly because CT was unable to distinguish between active or recurrent disease and residual scar tissue after therapy. FDG tumour uptake was found in high- as well as low-grade NHL patients. In conclusion, PET appears to be highly sensitive and specific for staging of lymphoma. It is at least as sensitive as CT, and more specific, particularly in patients undergoing restaging, where a well-recognized diagnostic dilemma in CT is the presence of a post-therapeutic residual mass. (orig.)

  11. Simultaneous multivessel coronary artery spasm demonstrated by quantitative analysis of thallium-201 single photon emission computed tomography

    International Nuclear Information System (INIS)

    Kugiyama, K.; Yasue, H.; Okumura, K.; Minoda, K.; Takaoka, K.; Matsuyama, K.; Kojima, A.; Koga, Y.; Takahashi, M.

    1987-01-01

    Thallium-201 myocardial scintigraphy with quantitative analysis of emission computed tomography was performed during episodes of angina in 19 patients with variant angina and nearly normal coronary arteriographic findings. Eleven patients (group I) were shown by arteriography to have spasm in 2 or more large coronary arteries. Eight patients (group II) had spasm in only 1 coronary artery. In 7 patients in group I, significant diffuse perfusion defects simultaneously appeared in multiple coronary artery regions on the scintigram (group IA). The extent and severity of the perfusion defect as measured by thallium-201 tomography were significantly greater in group IA than in group II (p less than 0.001 and p less than 0.01, respectively). The duration of transient ST-segment elevation during the attack in group IA was significantly longer than in group II (p less than 0.001). The incidence of ventricular arrhythmias, including ventricular tachycardia, or complete atrioventricular block during the anginal attack was significantly higher (p less than 0.05) in group IA than in group II. In all study patients, neither attack nor scintigraphic perfusion defect appeared on the repeat test after oral administration of nifedipine. In conclusion, multivessel coronary artery spasm simultaneously appears and causes the attack in many patients with variant angina and nearly normal coronary arteriographic findings, and myocardial ischemia due to simultaneous multivessel coronary spasm is likely to be more extensive and severe, persist longer and have a higher frequency of potentially dangerous arrhythmias than that due to spasm of only 1 coronary artery

  12. Computed tomography myocardial perfusion vs {sup 15}O-water positron emission tomography and fractional flow reserve

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Michelle C.; Dweck, Marc R.; Golay, Saroj K. [University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, Edinburgh (United Kingdom); Mirsadraee, Saeed; Weir, Nicholas W.; Fletcher, Alison; Lucatelli, Christophe; Reid, John H. [University of Edinburgh, Clinical Research Imaging Centre, Edinburgh (United Kingdom); MacGillivray, Tom; Van Beek, Edwin J.R.; Newby, David E. [University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, Edinburgh (United Kingdom); University of Edinburgh, Clinical Research Imaging Centre, Edinburgh (United Kingdom); Cruden, Nicholas L.; Henriksen, Peter A.; Uren, Neal [Edinburgh Heart Centre, Royal Infirmary of Edinburgh, Edinburgh (United Kingdom); McKillop, Graham; Patel, Dilip [Department of Radiology, Royal Infirmary of Edinburgh, Edinburgh (United Kingdom); Lima, Joao A.C. [Johns Hopkins Hospital, Departments of Medicine and Radiology, Baltimore, MD (United States)

    2017-03-15

    Computed tomography (CT) can perform comprehensive cardiac imaging. We compared CT coronary angiography (CTCA) and CT myocardial perfusion (CTP) with {sup 15}O-water positron emission tomography (PET) and invasive coronary angiography (ICA) with fractional flow reserve (FFR). 51 patients (63 (61-65) years, 80 % male) with known/suspected coronary artery disease (CAD) underwent 320-multidetector CTCA followed by ''snapshot'' adenosine stress CTP. Of these 22 underwent PET and 47 ICA/FFR. Obstructive CAD was defined as CTCA stenosis >50 % and CTP hypoperfusion, ICA stenosis >70 % or FFR <0.80. PET hyperaemic myocardial blood flow (MBF) was lower in obstructive than non-obstructive territories defined by ICA/FFR (1.76 (1.32-2.20) vs 3.11 (2.44-3.79) mL/(g/min), P < 0.001) and CTCA/CTP (1.76 (1.32-2.20) vs 3.12 (2.44-3.79) mL/(g/min), P < 0.001). Baseline and hyperaemic CT attenuation density was lower in obstructive than non-obstructive territories (73 (71-76) vs 86 (84-88) HU, P < 0.001 and 101 (96-106) vs 111 (107-114) HU, P 0.001). PET hyperaemic MBF corrected for rate pressure product correlated with CT attenuation density (r = 0.579, P < 0.001). There was excellent per-patient sensitivity (96 %), specificity (85 %), negative predictive value (90 %) and positive predictive value (94 %) for CTCA/CTP vs ICA/FFR. CT myocardial attenuation density correlates with {sup 15}O-water PET MBF. CTCA and CTP can accurately identify obstructive CAD. (orig.)

  13. Performance of Thallium-201 Electrocardiography-gated Myocardial Perfusion Single Photon Emission Computed Tomography to Assess Left Ventricular Function

    Directory of Open Access Journals (Sweden)

    Guang-Uei Hung

    2005-05-01

    Full Text Available This study evaluated the performance of gated single photon emission computed tomography (SPECT with thallium-201 (201Tl in assessing left ventricular ejection fraction (LVEF, end-diastolic volume (EDV, and end-systolic volume (ESV in Taiwanese by determining repeatability and correlation with two-dimensional (2D echocardiography. A total of 18 patients underwent two sequential gated SPECT acquisitions within 30 minutes in the resting state to assess repeatability. Another 28 patients who underwent gated SPECT and 2D echocardiography within 7 days were included for comparison. The two sequential measurements were well correlated with respect to LVEF, EDV, and ESV (r = 0.97, 0.95, and 0.97, respectively, all p < 0.0001. Bland-Altman analysis revealed that two standard deviations of the absolute difference between the two sequential measurements for LVEF, EDV, and ESV were 6.4%, 16.8 mL, and 8.6 mL, respectively. For LVEF, EDV, and ESV, correlations between redistribution 201Tl-gated SPECT and echocardiography were also excellent (all r = 0.83, p < 0.0001. LVEF was similar with 201Tl-gated SPECT and echocardiography, but EDV and ESV were significantly higher with echocardiography (p < 0.05. Our study revealed that 201Tl-gated SPECT has high repeatability and excellent correlation with echocardiography for the assessment of LVEF and volumes in Taiwanese. These results support the clinical application of gated SPECT in routine 201Tl myocardial perfusion imaging in Taiwanese.

  14. Whole-body 18F FDG positron emission tomography/computed tomography evaluation of patients with uveal metastasis.

    Science.gov (United States)

    Patel, Payal; Finger, Paul T

    2012-04-01

    To investigate the value of whole-body positron emission tomography/computed tomography (PET/CT) as a screening tool for patients with uveal metastasis. Retrospective observational case series. setting: Clinical practice. study population: Eighteen patients with uveal metastatic tumors were evaluated. Patients had no history of malignancy or a past medical history of malignancy without known active metastasis or known systemic cancer. intervention: Whole-body PET/CT was used as a screening tool to evaluate the intraocular tumor, to evaluate for multi-organ metastatic disease, and for cancer staging. main outcome measures: Detection and PET/CT uptake of primary tumors and metastatic disease. PET/CT imaging uncovered previously occult primary nonocular cancers (11/18, 61%), revealed progression of known primary systemic cancer (7/18, 39%), and confirmed multi-organ metastases in all cases (18/18, 100%). PET/CT findings were used to direct nonocular, confirmatory biopsy in 67% of cases (12/18). No uveal biopsies were required. PET/CT revealed lymph nodes and bone as the most common metastatic sites. The intraocular tumor was detectable in 28% of cases. Small, non-avid tumors and those within the hypermetabolic, PET-avid brain were falsely negative. This study suggests that whole-body PET/CT can be useful for clinical evaluation of patients with uveal metastases. It allowed for screening of the entire body and directed extraocular biopsy. Commonly used for tumor staging, PET/CT aided in the detection of the primary cancer in patients with metastatic uveal tumors. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Single photon emission-computed tomography (SPECT) for functional investigation of the proximal tubule in conscious mice.

    Science.gov (United States)

    Jouret, François; Walrand, Stéphan; Parreira, Kleber S; Courtoy, Pierre J; Pauwels, Stanislas; Devuyst, Olivier; Jamar, François

    2010-02-01

    Noninvasive analysis of renal function in conscious mice is necessary to optimize the use of mouse models. In this study, we evaluated whether single photon emission-computed tomography (SPECT) using specific radionuclear tracers can be used to analyze changes in renal proximal tubule functions. The tracers included (99m)TC- dimercaptosuccinic acid ((99m)Tc-DMSA), which is used for cortex imaging; (99m)Tc-mercaptoacetyltriglycine ((99m)Tc-MAG3), used for dynamic renography; and (123)I-beta(2)-microglobulin, which monitors receptor-mediated endocytosis. (99m)Tc-DMSA SPECT imaging was shown to delineate the functional renal cortex with a approximately 1-mm spatial resolution and accumulated in the cortex reaching a plateau 5 h after injection. The cortical uptake of (99m)Tc-DMSA was abolished in Clcn5 knockout mice, a model of proximal tubule dysfunction. Dynamic renography with (99m)Tc-MAG3 in conscious mice demonstrated rapid extraction from blood, renal accumulation, and subsequent tubular secretion. Anesthesia induced a significant delay in the (99m)Tc-MAG3 clearance. The tubular reabsorption of (123)I-beta(2)-microglobulin was strongly impaired in the Clcn5 knockout mice, with defective tubular processing and loss of the native tracer in urine, reflecting proximal tubule dysfunction. Longitudinal studies in a model of cisplatin-induced acute tubular injury revealed a correlation between tubular recovery and (123)I-beta(2)-microglobulin uptake. These data show that SPECT imaging with well-validated radiotracers allows in vivo investigations of specific proximal tubule functions in conscious mice.

  16. Regional cerebral blood flow measurement using N-isopropyl-p-[123I] iodoamphetamine and rotating gamma camera emission computed tomography

    International Nuclear Information System (INIS)

    Matsuda, Hiroshi; Seki, Hiroyasu; Ishida, Hiroko

    1985-01-01

    Thirty-one regional cerebral blood flow (rCBF) measurements were performed on 26 patients with cerebrovascular accidents using N-Isopropyl-p-[ 123 I] Iodoamphetamine ( 123 I-IMP) and rotating gamma camera emission computed tomography (ECT). The equation for determining rCBF is as follows: F=100.R.Cb/(N.A), where F is rCBF in ml/100 g/min., R is the constant withdrawal rate of arterial blood in ml/min., Cb is the brain activity concentration in μCi/g, A is the total activity (5 min.) in the withdrawal arterial whole blood in μCi and N is the fraction of A that is true tracer activity (0.75). In determining Cb at 5 min. after injection, reconstructed counts from 35 min. to 59 min. were corrected to represent those from 4 min. to 5 min. with the use of time activity curve for the entire brain immediately after injection to 30 min. Reconstructed counts of central region in tomographic image were corrected 118% of the obtained values from the result of the countingrate ratio between peripheral and central regions of interests obtained from phantom study. Brain mean blood flow values were distributed from 11 to 39 ml/100 g/min. In 119 cortical regions obtained from 11 measurements in 9 patients, there was a significant correlation (r=0.41, p 123 I-IMP and rotating gamma camera ECT and those from 133 Xe inhalation method. rCBF measurement using 123 I-IMP and rotating gamma camera ECT is not only relatively noninvasive measurement for the entire brain but also three-dimensional evaluation. Besides, it is superior in spatial resolution and accuracy to conventional 133 Xe clearance method. (author)

  17. Whole-body positron emission tomography using fluorodeoxyglucose for staging of lymphoma: effectiveness and comparison with computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Stumpe, K.D.M.; Urbinelli, M.; Steinert, H.C.; Glanzmann, C.; Buck, A.; von Schulthess, G.K. [Department of Medical Radiology, University Hospital, Zurich (Switzerland)

    1998-07-01

    The purpose of this study was to evaluate whole-body positron emission tomography (WB-PET) as a staging modality in Hodgkin`s disease (HD) and non-Hodgkin lymphoma (NHL) and to compare it with computed tomography (CT) in a retrospective study. Seventy-one WB-PET studies using fluorodeoxyglucose (FDG) and 49 CT examinations were performed in 19 women and 31 men. Transaxial images were acquired and reformatted coronally and sagittally in PET. CT sections were obtained from the skull base to the pelvic floor. The written reports of the imaging data were compared with a reference standard constructed on the basis of all the data on the individual patients, including clinical follow-up of at least 6 months. The sensitivity and specificity of PET were, respectively, 86% and 96% for HD (n=53), and 89% and 100% for NHL (n=18). For CT sensitivity and specificity were 81% and 41% for HD (n=33) and 86% and 67% for NHL (n=16). Differences between PET and CT sensitivities were not significant, while in HD there was a significant difference in the specificity of PET and CT examinations, mainly because CT was unable to distinguish between active or recurrent disease and residual scar tissue after therapy. FDG tumour uptake was found in high- as well as low-grade NHL patients. In conclusion, PET appears to be highly sensitive and specific for staging of lymphoma. It is at least as sensitive as CT, and more specific, particularly in patients undergoing restaging, where a well-recognized diagnostic dilemma in CT is the presence of a post-therapeutic residual mass. (orig.) With 4 figs., 3 tabs., 23 refs.

  18. Brain areas involved in acupuncture needling sensation of de qi: a single-photon emission computed tomography (SPECT) study.

    Science.gov (United States)

    Chen, Jia-Rong; Li, Gan-Long; Zhang, Gui-Feng; Huang, Yong; Wang, Shu-Xia; Lu, Na

    2012-12-01

    De qi is a sensory response elicited by acupuncture stimulation. According to traditional Chinese medicine (TCM), de qi is essential for clinical efficacy. However, the understanding of the neurobiological basis of de qi is still limited. To investigate the relationship between brain activation and de qi by taking a single-photon emission computed tomography (SPECT) scan while applying acupuncture at TE5. A total of 24 volunteers were randomly divided into 4 groups, and received verum or sham acupuncture at true acupuncture point TE5 or a nearby sham point according to grouping. All subjects then received a (99m)Tc-ethylcysteinate dimer (ECD) SPECT scan. All six subjects in the verum acupuncture at true acupuncture point group experienced de qi sensation; in contrast, all six subjects in the sham acupuncture at the sham point group responded with nothing other than non-sensation. Compared to the scan results from subjects who experienced non-sensation, SPECT scans from subjects with de qi sensation demonstrated significant activated points mainly located in brodmann areas 6, 8, 19, 21, 28, 33, 35, 37, 47, the parahippocampal gyrus, lentiform nucleus, claustrum and red nucleus; deactivated points were seen in brodmann areas 9 and 25. Verum acupuncture at true acupuncture points is more likely to elicit de qi sensation. De qi sensations mainly resulted in brain area activations, but not deactivations. These brain areas are related to the curative effect of Te5. The acupuncture needle sensations of de qi and sharp pain are associated with different patterns of activations and deactivations in the brain.

  19. Correlative single photon emission computed tomography imaging of [123I]altropane binding in the rat model of Parkinson's

    International Nuclear Information System (INIS)

    Gleave, Jacqueline A.; Farncombe, Troy H.; Saab, Chantal; Doering, Laurie C.

    2011-01-01

    Introduction: This study used the dopamine transporter (DAT) probe, [ 123 I]-2β-carbomethoxy-3β-(4-fluorophenyl)-N-(3-iodo-E-allyl)nortropane ([ 123 I]altropane), to assess the DAT levels in the 6-hydroxydopamine rat model of Parkinson's disease. We sought to assess if the right to left [ 123 I]altropane striatal ratios correlated with dopamine content in the striatum and substantia nigra and with behavioural outcomes. Methods: [ 123 I]altropane images taken pre- and postlesion were acquired before and after the transplantation of neural stem/progenitor cells. The images obtained using [ 123 I]altropane and single photon emission computed tomography (SPECT) were compared with specific behavioural tests and the dopamine content assessed by high-performance liquid chromatography. Results: [ 123 I]altropane binding correlated with the content of dopamine in the striatum; however, [ 123 I]altropane binding did not correlate with the dopamine content in the substantia nigra. There was a significant correlation of altropane ratios with the cylinder test and the postural instability test, but not with amphetamine rotations. The low coefficient of determination (r 2 ) for these correlations indicated that [ 123 I]altropane SPECT was not a good predictor of behavioural outcomes. Conclusion: Our data reveal that [ 123 I]altropane predicts the integrity of the striatal dopamine nerve terminals, but does not predict the integrity of the nigrostriatal system. [ 123 I]altropane could be a useful marker to measure dopamine content in cell replacement therapies; however, it would not be able to evaluate outcomes for neuroprotective strategies.

  20. Investigation of the Feasibility of Utilizing Gamma Emission Computed Tomography in Evaluating Fission Product Migration in Irradiated TRISO Fuel Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Jason M. Harp; Paul A. Demkowicz

    2014-10-01

    In the High Temperature Gas-Cooled Reactor (HTGR) the TRISO particle fuel serves as the primary fission product containment. However the large number of TRISO particles present in proposed HTGRs dictates that there will be a small fraction (~10-4 to 10-5) of as manufactured and in-pile particle failures that will lead to some fission product release. The matrix material surrounding the TRISO particles in fuel compacts and the structural graphite holding the TRISO particles in place can also serve as sinks for containing any released fission products. However data on the migration of solid fission products through these materials is lacking. One of the primary goals of the AGR-3/4 experiment is to study fission product migration from failed TRISO particles in prototypic HTGR components such as structural graphite and compact matrix material. In this work, the potential for a Gamma Emission Computed Tomography (GECT) technique to non-destructively examine the fission product distribution in AGR-3/4 components and other irradiation experiments is explored. Specifically, the feasibility of using the Idaho National Laboratory (INL) Hot Fuels Examination Facility (HFEF) Precision Gamma Scanner (PGS) system for this GECT application is considered. To test the feasibility, the response of the PGS system to idealized fission product distributions has been simulated using Monte Carlo radiation transport simulations. Previous work that applied similar techniques during the AGR-1 experiment will also be discussed as well as planned uses for the GECT technique during the post irradiation examination of the AGR-2 experiment. The GECT technique has also been applied to other irradiated nuclear fuel systems that were currently available in the HFEF hot cell including oxide fuel pins, metallic fuel pins, and monolithic plate fuel.

  1. Clinicopathological correlation for the role of fluorodeoxyglucose positron emission tomography computed tomography in detection of choroidal malignant melanoma

    International Nuclear Information System (INIS)

    Matsuo, Toshihiko; Ogino, Yuka; Ichimura, Kouichi; Tanaka, Takehiro; Kaji, Mitsumasa

    2014-01-01

    The purpose of this study was to redefine the role of whole-body 2-[ 18 F]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography fused with computed tomography (PET/CT) in the clinical diagnosis of choroidal malignant melanoma. The study design was a retrospective case series involving 7 consecutive patients with choroidal malignant melanoma who underwent enucleation to reach the final pathological diagnosis. FDG-PET/CT was performed together with magnetic resonance imaging and ophthal-mological examinations before the surgery. The area, thickness, longest diameter, and circumference of the tumor mass were measured on pathological sections, and were correlated with maximum standardized uptake values (SUVmax) of the tumors on FDG-PET/CT. Abnormally high uptake of FDG was noted in the affected eyes of 5 patients, but not in the eyes of 2 patients. The 5 patients with high uptake showed nodular tumors extruding into the vitreous cavity while the 2 patients with absence of uptake showed diffusely infiltrating tumors in the wide area of the choroid with or without a small mushroom-like protrusion. One patient with diffuse infiltration showed concurrent liver metastases with high uptake on PET/CT while another patient with a nodular tumor developed liver metastases a year later. The tumors with higher SUVmax had a tendency to have a wider area and greater thickness on pathological sections (p=0.775, P=0.0557, Spearman rank correlation test). FDG-PET/CT showed correlation of the uptake with tumor sizes but was limited in detecting diffusely infiltrating tumors in the choroid without nodular formation. (author)

  2. Prognostic Value of Volume-Based Positron Emission Tomography/Computed Tomography in Nasopharyngeal Carcinoma Patients after Comprehensive Therapy

    Directory of Open Access Journals (Sweden)

    Yueli Tian

    2018-01-01

    Full Text Available Objective. We assessed the prognostic value of standardized uptake value (SUV and volume-based methods including whole-body metabolic tumor volume (WBMTV and whole-body total lesion glycolysis (WBTLG using 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT of patients with nasopharyngeal carcinoma (NPC after therapy. Methods. A total of 221 posttherapy NPC cases were enrolled, all of whom had undergone PET/CT scanning and follow-up in this retrospective study. The diagnostic results of PET/CT were analyzed and compared with histopathological diagnosis or clinical follow-up. Receiver operator characteristic curves, the Kaplan-Meier method, and the log-rank test were used to assess the optimal cutoff values for WBMTV and WBTLG to identify independent predictors of survival. Results. The detection rates of the threshold SUV were 2.5, 20%, and 40%, and SUV background methods were 65.6% (378/576, 80.2% (462/576, 71.5% (412/576, and 90.4% (521/576, respectively (P<0.005. Patients with a WBMTV < 8.10 and/or a WBTLG < 35.58 had significantly better 5-year overall survival than those above the cutoffs (90.7% versus 51.2%, P<0.001; 91.7% versus 50.4%, P<0.001, respectively. Multivariate Cox regression modeling showed both WBTLG (RR, 1.002; P=0.004 and age (RR, 1.046; P=0.006 could be used to predict overall survival. WBTLG (RR, 1.003; P<0.001 may have predictive relevance in estimating disease-free survival. Conclusions. SUV volume-based threshold background methodology had a significantly higher detection rate for metastatic lesions. WBTLG could be used as an independent prognostic indicator for posttherapy NPC.

  3. New trials for improving diagnostic accuracy of stress technetium-99m-tetrofosmin single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Ryu [Fujisawa City Hospital, Kanagawa (Japan); Mitani, Isao; Kitamura, Yutaka; Nemoto, Toyoji; Tsukahara, Kengo; Tanaka, Yutaka; Higuma, Kikuhiko

    2002-01-01

    This study evaluated the influence of extra-cardiac accumulation in technetium-99m-tetrofosmin myocardial single photon emission computed tomography (SPECT) imaging. Technetium-99m-tetrofosmin myocardial SPECT was performed in 247 patients from 1997 to 1999. To evaluate the sensitivity, 42 patients with inferior infarction were selected. To evaluate the specificity, 32 patients with no significant perfusion defect and low pretest likelihood (<15%) of coronary artery disease and 13 patients with normal coronary angiography were selected. Firstly, the SPECT raw data were evaluated according to the effects of diaphragm and breast, the position and the degree of accumulation of the liver, gall bladder and intestine. Then, the myocardial tracer uptake was scored semiquantitatively from 0 (normal) to 4 (perfusion defect) in the 13 segments of the left ventricle. The specificity was 86.7% and the sensitivity was 92.8%. Perfusion abnormality of the inferior wall was observed in 6 of 45 patients with a low pretest likelihood of coronary artery disease. These 6 patients were classified into the false positive group, and the other 39 patients were classified into the true negative group. The liver position and the liver accumulation on the stress images were significantly higher in the false positive group than in the true negative group (p<0.001), but only the liver position on the rest images was significantly higher in the false positive group (p<0.001). By estimating the defect 1 point lower for the high-positioned liver patients, specificity improved from 86.7% to 100% and sensitivity did not change. Inferior perfusion defect on technetium-99m-tetrofosmin myocardial SPECT of high-positioned liver patients needs to be evaluated with special caution. (author)

  4. Beneficial effect of coronary artery bypass grafting as assessed by quantitative gated single-photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hida, Satoshi; Chikamori, Taishiro; Hirayama, Tetsuzo; Usui, Yasuhiro; Yanagisawa, Hidefumi; Morishima, Takayuki; Ishimaru, Shin; Yamashina, Akira [Tokyo Medical Coll. (Japan)

    2003-06-01

    The development of quantitative gated single-photon emission computed tomography (SPECT) has enabled the assessment of left ventricular perfusion, function and wall thickness in a single examination. Accordingly, the present study used gated SPECT to assess the benefit of coronary artery bypass grafting (CABG) in patients with coronary artery disease; 47 of those patients were evaluated before and 5 months after CABG. As a result of coronary revascularization, a significant improvement was observed in global ejection fraction (50{+-}12{yields}53{+-}11%; p<0.05). In 107 revascularized territories, the average regional reversible defect score (0.8{+-}0.5{yields}0.2{+-}0.3; p<0.0001), average regional perfusion score at rest (0.6{+-}0.6{yields}0.3{+-}0.4; p<0.0001), average regional wall motion score (0.9{+-}0.7{yields}0.7{+-}0.5; p<0.05), and end-diastolic wall thickness (8.1{+-}1.3{yields}8.6{+-}1.5 mm; p<0.0005) all improved significantly. Even in 34 non-revascularized territories, the average regional reversible defect score (0.5{+-}0.7{yields}0.2{+-}0.5; p<0.03), average regional wall motion score (0.8{+-}1.1{yields}0.5{+-}1.0; p<0.03) and end-diastolic wall thickness (8.0{+-}1.4{yields}9.1{+-}2.0 mm; p<0.03) all improved significantly. These results indicate that improvement in myocardial ischemia, hibernation and left ventricular function with CABG can be assessed in detail with gated SPECT. (author)

  5. Assessment of radiation dose in nuclear cardiovascular imaging using realistic computational models

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Tianwu [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, Geneva 4 CH-1211 (Switzerland); Lee, Choonsik [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institute of Health, Bethesda, Maryland 20852 (United States); Bolch, Wesley E. [Departments of Nuclear and Radiological and Biomedical Engineering, University of Florida, Gainesville, Florida 32611 (United States); Zaidi, Habib, E-mail: habib.zaidi@hcuge.ch [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, Geneva 4 CH-1211 (Switzerland); Geneva Neuroscience Center, Geneva University, Geneva CH-1205 (Switzerland); Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen 9700 RB (Netherlands)

    2015-06-15

    Purpose: Nuclear cardiology plays an important role in clinical assessment and has enormous impact on the management of a variety of cardiovascular diseases. Pediatric patients at different age groups are exposed to a spectrum of radiation dose levels and associated cancer risks different from those of adults in diagnostic nuclear medicine procedures. Therefore, comprehensive radiation dosimetry evaluations for commonly used myocardial perfusion imaging (MPI) and viability radiotracers in target population (children and adults) at different age groups are highly desired. Methods: Using Monte Carlo calculations and biological effects of ionizing radiation VII model, we calculate the S-values for a number of radionuclides (Tl-201, Tc-99m, I-123, C-11, N-13, O-15, F-18, and Rb-82) and estimate the absorbed dose and effective dose for 12 MPI radiotracers in computational models including the newborn, 1-, 5-, 10-, 15-yr-old, and adult male and female computational phantoms. Results: For most organs, {sup 201}Tl produces the highest absorbed dose whereas {sup 82}Rb and {sup 15}O-water produce the lowest absorbed dose. For the newborn baby and adult patient, the effective dose of {sup 82}Rb is 48% and 77% lower than that of {sup 99m}Tc-tetrofosmin (rest), respectively. Conclusions: {sup 82}Rb results in lower effective dose in adults compared to {sup 99m}Tc-labeled tracers. However, this advantage is less apparent in children. The produced dosimetric databases for various radiotracers used in cardiovascular imaging, using new generation of computational models, can be used for risk-benefit assessment of a spectrum of patient population in clinical nuclear cardiology practice.

  6. Reshaping of computational system for dosimetry in neutron and photons radiotherapy based in stochastic methods - SISCODES

    International Nuclear Information System (INIS)

    Trindade, Bruno Machado

    2011-02-01

    This work shows the remodeling of the Computer System for Dosimetry of Neutrons and Photons in Radiotherapy Based on Stochastic Methods . SISCODES. The initial description and status, the alterations and expansions (proposed and concluded), and the latest system development status are shown. The SISCODES is a system that allows the execution of a 3D computational planning in radiation therapy, based on MCNP5 nuclear particle transport code. The SISCODES provides tools to build a patient's voxels model, to define a treatment planning, to simulate this planning, and to view the results of the simulation. The SISCODES implements a database of tissues, sources and nuclear data and an interface to access then. The graphical SISCODES modules were rewritten or were implemented using C++ language and GTKmm library. Studies about dose deviations were performed simulating a homogeneous water phantom as analogue of the human body in radiotherapy planning and a heterogeneous voxel phantom, pointing out possible dose miscalculations. The Soft-RT and PROPLAN computer codes that do interface with SISCODES are described. A set of voxels models created on the SISCODES are presented with its respective sizes and resolutions. To demonstrate the use of SISCODES, examples of radiation therapy and dosimetry simulations for prostate and heart are shown. Three protocols were simulated on the heart voxel model: Sm-153 filled balloon and P-32 stent, to prevent angioplasty restenosis; and Tl-201 myocardial perfusion, to imaging. Teletherapy with 6MV and 15MV beams were simulated to the prostate, and brachytherapy with I-125 seeds. The results of these simulations are shown on isodose curves and on dose-volume histograms. The SISCODES shows to be a useful tool for research of new radiation therapy treatments and, in future, can also be useful in medical practice. At the end, future improvements are proposed. I hope this work can contribute to develop more effective radiation therapy

  7. The utility of 68Ga-DOTATATE positron-emission tomography/computed tomography in the diagnosis, management, follow-up and prognosis of neuroendocrine tumors.

    Science.gov (United States)

    Tirosh, Amit; Kebebew, Electron

    2018-01-01

    Neuroendocrine tumors (NETs) are rare neoplasms that emerge mainly from the GI tract, pancreas and respiratory tract. The incidence of NETs has increased more than sixfold in the last decades. NETs typically express somatostatin receptors on their cell surface, which can be targeted by 'cold' somatostatin analogs for therapy or by 'hot' radiolabeled somatostatin analogs for tumor localization and treatment. 68-Gallium-DOTA peptides (DOTATATE, DOTATOC, DOTANOC) positron emission tomography/computed tomography is a highly accurate imaging modality for NETs that has been found to be more sensitive for NET detection than other imaging modalities. In the current review, we will discuss the clinical utility of 68-Gallium-DOTATATE positron emission tomography/computed tomography for the diagnosis and management of patients with NETs.

  8. COMPUTING

    CERN Multimedia

    I. Fisk

    2013-01-01

    Computing activity had ramped down after the completion of the reprocessing of the 2012 data and parked data, but is increasing with new simulation samples for analysis and upgrade studies. Much of the Computing effort is currently involved in activities to improve the computing system in preparation for 2015. Operations Office Since the beginning of 2013, the Computing Operations team successfully re-processed the 2012 data in record time, not only by using opportunistic resources like the San Diego Supercomputer Center which was accessible, to re-process the primary datasets HTMHT and MultiJet in Run2012D much earlier than planned. The Heavy-Ion data-taking period was successfully concluded in February collecting almost 500 T. Figure 3: Number of events per month (data) In LS1, our emphasis is to increase efficiency and flexibility of the infrastructure and operation. Computing Operations is working on separating disk and tape at the Tier-1 sites and the full implementation of the xrootd federation ...

  9. An Incidentally Found Inflamed Uterine Myoma Causing Low Abdominal Pain, Using Tc-99m-Tektrotyd Single Photon Emission Computed Tomography-CT Hybrid Imaging

    OpenAIRE

    Zandieh, Shahin; Sch?tz, Matthias; Bernt, Reinhard; Zwerina, Jochen; Haller, Joerg

    2013-01-01

    We report the case of a 50-year-old woman presented with a history of right hemicolectomy due to an ileocecal neuroendocrine tumor and left breast metastasis. Owing to a slightly elevated chromogranin A-level and lower abdominal pain, single photon emission computed tomography-computer tomography (SPECT-CT) was performed. There were no signs of recurrence on the SPECT-CT scan, but the patient was incidentally found to have an inflamed intramural myoma. We believe that the slightly elevated ch...

  10. Review of cardiovascular imaging in the journal of nuclear cardiology in 2015. Part 1 of 2: Plaque imaging, positron emission tomography, computed tomography, and magnetic resonance.

    Science.gov (United States)

    AlJaroudi, Wael A; Hage, Fadi G

    2016-02-01

    In 2015, many original articles pertaining to cardiovascular imaging with impressive quality were published in the Journal of Nuclear Cardiology. In a set of 2 articles, we provide an overview of these contributions to facilitate for the interested reader a quick review of the advancements that occurred in the field over this year. In this first article, we focus on arterial plaque imaging, cardiac positron emission tomography, computed tomography, and magnetic resonance imaging.

  11. Rare case of isolated splenic metastases from gastric cancer detected with fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography

    International Nuclear Information System (INIS)

    Kamaleshwaran, Koramadai Karuppusamy; Shibu, Deepu; Sugunan Shinto, Ajit; Sivanesan, Balasubramanian

    2013-01-01

    We report a rare case of isolated splenic metastasis from gastric cancer detected with fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography (PET/CT). A 55-year-old man with gastric cancer 1 year post surgery, evaluated with PET/CT showed focal, intense uptake in the spleen, with no other abnormal findings. On splenectomy, the lesion was confirmed as metastasis from gastric cancer pathologically. (author)

  12. Prostate cancer nodal oligometastasis accurately assessed using prostate-specific membrane antigen positron emission tomography-computed tomography and confirmed histologically following robotic-assisted lymph node dissection

    Directory of Open Access Journals (Sweden)

    Dermot B O′Kane

    2016-01-01

    Full Text Available We herein present a case of a 76-year-old gentleman, where prostate-specific membrane antigen positron emission tomography-computed tomography (PSMA PET-CT was used to accurately detect prostate cancer (PCa, pelvic lymph node (LN metastasis in the setting of biochemical recurrence following definitive treatment for PCa. The positive PSMA PET-CT result was confirmed with histological examination of the involved pelvic LNs following pelvic LN dissection.

  13. Post meningitis subdural hygroma: Anatomical and functional evaluation with 99mTc-ehylene cysteine dimer single photon emission tomography/computed tomography

    OpenAIRE

    Sharma, Punit; Mishra, Ajiv; Arora, Geetanjali; Tripathi, Madhavi; Bal, Chandrasekhar; Kumar, Rakesh

    2013-01-01

    Subdural hygroma is the collection of cerebrospinal fluid in the subdural space. Most often these resolve spontaneously. However, in cases with neurological complications surgical drainage may be needed. We here, present the case of an 8-year-old boy with post meningitis subdural hygroma. 99mTc-ehylene cysteine dimer (99mTc-ECD) hybrid single photon emission tomography/computed tomography (SPECT/CT) carried out in this patient, demonstrated the subdural hygroma as well as the associated cereb...

  14. Pancreatic tuberculosis: Evaluation of therapeutic response using F-18 fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography

    International Nuclear Information System (INIS)

    Santhosh, Sampath; Bhattacharya, Anish; Rana, Surinder Singh; Bhasin, Deepak Kumar; Srinivasan, Radhika; Mittal, Bhagwant Rai

    2014-01-01

    F-18 fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG PET/CT) is a functional imaging technique that monitors glucose metabolism in tissues. Pulmonary tuberculosis (TB) has been reported to show intense uptake of FDG, with a decrease in metabolism of the tuberculous lesions after successful anti-tubercular treatment (ATT). The authors present a patient with pancreatic TB and demonstrate the usefulness of FDG PET/CT in monitoring the response to ATT

  15. Noninvasive evaluation of active pan-ulcerative colitis with multiple strictures using Fluorine-18-Fluorodeoxyglucose positron emission tomography/computed tomography

    International Nuclear Information System (INIS)

    Santhosh, Sampath; Bhattacharya, Anish; Rana, Surinder Singh; Bhasin, Deepak Kumar; Gupta, Rajesh; Mittal, Bhagwant Rai

    2016-01-01

    Ulcerative colitis (UC) is an inflammatory bowel disease characterized by waxing and waning inflammation that changes in severity and extent and may progress to neoplasia, especially in the presence of strictures. When patients have nonnegotiable strictures or severe inflammation with ulcers, colonoscopy is difficult and carries the risk of perforation. The authors present a patient with pan-UC with multiple strictures, in whom fluorodeoxyglucose positron emission tomography/computed tomography was used to noninvasively evaluate the extent and severity of the disease

  16. Unusual presentation of metastatic carcinoma cervix with clinically silent primary identified by 18F-flouro deoxy glucose positron emission tomography/computed tomography

    International Nuclear Information System (INIS)

    Senthil, Raja; Mohapatra, Ranjan Kumar; Srinivas, Shripriya; Sampath, Mouleeswaran Koramadai; Sundaraiya, Sumati

    2016-01-01

    Carcinoma cervix is the most common gynecological malignancy among Indian women. The common symptoms at presentation include abnormal vaginal bleeding, unusual discharge from the vagina, or pain during coitus and postmenopausal bleeding. Rarely, few patients may present with distant metastases without local symptoms. We present two patients with an unusual presentation of metastatic disease without any gynecological symptoms, where 18 F-flouro deoxy glucose positron emission tomography/computed tomography helped in identifying the primary malignancy in the uterine cervix

  17. Prostate cancer nodal oligometastasis accurately assessed using prostate-specific membrane antigen positron emission tomography-computed tomography and confirmed histologically following robotic-assisted lymph node dissection.

    Science.gov (United States)

    O'Kane, Dermot B; Lawrentschuk, Nathan; Bolton, Damien M

    2016-01-01

    We herein present a case of a 76-year-old gentleman, where prostate-specific membrane antigen positron emission tomography-computed tomography (PSMA PET-CT) was used to accurately detect prostate cancer (PCa), pelvic lymph node (LN) metastasis in the setting of biochemical recurrence following definitive treatment for PCa. The positive PSMA PET-CT result was confirmed with histological examination of the involved pelvic LNs following pelvic LN dissection.

  18. Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Imaging in Patients With Carcinoma of the Nasopharynx: Diagnostic Accuracy and Impact on Clinical Management

    International Nuclear Information System (INIS)

    Gordin, Arie; Golz, Avishay; Daitzchman, Marcello; Keidar, Zohar; Bar-Shalom, Rachel; Kuten, Abraham; Israel, Ora

    2007-01-01

    Purpose: To assess the value of 18 F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in patients with nasopharyngeal carcinoma as compared with PET and conventional imaging (CI) alone, and to assess the impact of PET/CT on further clinical management. Methods and Materials: Thirty-three patients with nasopharyngeal carcinoma had 45 PET/CT examinations. The study was a retrospective analysis. Changes in patient care resulting from the PET/CT studies were recorded. Results: Positron emission tomography/computed tomography had sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 92%, 90%, 90%, 90%, and 91%, respectively, as compared with 92%, 65%, 76%, 86%, and 80% for PET and 92%, 15%, 60%, 60%, and 60% for CI. Imaging with PET/CT altered further management of 19 patients (57%). Imaging with PET/CT eliminated the need for previously planned diagnostic procedures in 11 patients, induced a change in the planned therapeutic approach in 5 patients, and guided biopsy to a specific metabolically active area inside an edematous region in 3 patients, thus decreasing the chances for tissue sampling errors and avoiding damage to nonmalignant tissue. Conclusions: In cancer of the nasopharynx, the diagnostic performance of PET/CT is better than that of stand-alone PET or CI. Positron emission tomography/computed tomography had a major impact on further clinical management in 57% of patients

  19. Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography imaging in patients with carcinoma of the nasopharynx: diagnostic accuracy and impact on clinical management.

    Science.gov (United States)

    Gordin, Arie; Golz, Avishay; Daitzchman, Marcello; Keidar, Zohar; Bar-Shalom, Rachel; Kuten, Abraham; Israel, Ora

    2007-06-01

    To assess the value of (18)F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in patients with nasopharyngeal carcinoma as compared with PET and conventional imaging (CI) alone, and to assess the impact of PET/CT on further clinical management. Thirty-three patients with nasopharyngeal carcinoma had 45 PET/CT examinations. The study was a retrospective analysis. Changes in patient care resulting from the PET/CT studies were recorded. Positron emission tomography/computed tomography had sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 92%, 90%, 90%, 90%, and 91%, respectively, as compared with 92%, 65%, 76%, 86%, and 80% for PET and 92%, 15%, 60%, 60%, and 60% for CI. Imaging with PET/CT altered further management of 19 patients (57%). Imaging with PET/CT eliminated the need for previously planned diagnostic procedures in 11 patients, induced a change in the planned therapeutic approach in 5 patients, and guided biopsy to a specific metabolically active area inside an edematous region in 3 patients, thus decreasing the chances for tissue sampling errors and avoiding damage to nonmalignant tissue. In cancer of the nasopharynx, the diagnostic performance of PET/CT is better than that of stand-alone PET or CI. Positron emission tomography/computed tomography had a major impact on further clinical management in 57% of patients.

  20. Simultaneous 68Ga DOTATATE Positron Emission Tomography/Magnetic Resonance Imaging in Meningioma Target Contouring: Feasibility and Impact Upon Interobserver Variability Versus Positron Emission Tomography/Computed Tomography and Computed Tomography/Magnetic Resonance Imaging.

    Science.gov (United States)

    Maclean, J; Fersht, N; Sullivan, K; Kayani, I; Bomanji, J; Dickson, J; O'Meara, C; Short, S

    2017-07-01

    The increasing use of highly conformal radiation techniques to treat meningioma confers a greater need for accurate targeting. Several groups have shown that positron emission tomography/computed tomography (PET/CT) information alters meningioma targets contoured by single observers, but whether this translates into improved accuracy has not been defined. As magnetic resonance imaging (MRI) is the cornerstone of meningioma target contouring, simultaneous PET/MRI may be superior to PET/CT. We assessed whether 68 Ga DOTATATE PET imaging (from PET/CT and PET/MRI) reduced interobserver variability (IOV) in meningioma target volume contouring. Ten patients with meningioma underwent simultaneous 68 Ga DOTATATE PET/MRI followed by PET/CT. They were selected as it was anticipated that target volume definition in their cases would be particularly challenging. Three radiation oncologists contoured target volumes according to an agreed protocol: gross tumour volume (GTV) and clinical target volume (CTV) on CT/MRI alone, CT/MRI+PET(CT) and CT/MRI+PET(MRI). GTV/CTV Kouwenhoven conformity levels (KCL), regions of contour variation and qualitative differences between PET(CT) and PET(MRI) were evaluated. There was substantial IOV in contouring. GTV mean KCL: CT/MRI 0.34, CT/MRI+PET(CT) 0.38, CT/MRI+PET(MRI) 0.39 (P = 0.06). CTV mean KCL: CT/MRI 0.31, CT/MRI+PET(CT) 0.35, CT/MRI+PET(MRI) 0.35 (P = 0.04 for all groups; P > 0.05 for individual pairs). One observer consistently contoured largest and one smallest. Observers rarely decreased volumes in relation to PET. Most IOV occurred in bone followed by dural tail, postoperative bed and venous sinuses. Tumour edges were qualitatively clearer on PET(MRI) versus PET(CT), but this did not affect contouring. IOV in contouring challenging meningioma cases was large and only slightly improved with the addition of 68 Ga DOTATATE PET. Simultaneous PET/MRI for meningioma contouring is feasible, but did not improve IOV versus PET

  1. Validation of CFD simulation for ammonia emissions from an aqueous solution Submitted to Computers and Electronics in Agriculture

    DEFF Research Database (Denmark)

    Rong, Li; Elhadidi, B; Khalifa, H E

    2011-01-01

    In order to model and predict ammonia emissions from animal houses, it is important to determine the concentration on the emission surface correctly. In the current literature, Henry’s law is usually used to model the mass transfer through the gas–liquid surface (e.g. manure or aqueous solution)....

  2. Dystrophic calcification in muscles of legs in calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia syndrome: Accurate evaluation of the extent with (99m)Tc-methylene diphosphonate single photon emission computed tomography/computed tomography.

    Science.gov (United States)

    Chakraborty, Partha Sarathi; Karunanithi, Sellam; Dhull, Varun Singh; Kumar, Kunal; Tripathi, Madhavi

    2015-01-01

    We present the case of a 35-year-old man with calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly and telangiectasia variant scleroderma who presented with dysphagia, Raynaud's phenomenon and calf pain. (99m)Tc-methylene diphosphonate bone scintigraphy was performed to identify the extent of the calcification. It revealed extensive dystrophic calcification in the left thigh and bilateral legs which was involving the muscles and was well-delineated on single photon emission computed tomography/computed tomography. Calcinosis in scleroderma usually involves the skin but can be found in deeper periarticular tissues. Myopathy is associated with a poor prognosis.

  3. COMPUTING

    CERN Multimedia

    M. Kasemann P. McBride Edited by M-C. Sawley with contributions from: P. Kreuzer D. Bonacorsi S. Belforte F. Wuerthwein L. Bauerdick K. Lassila-Perini M-C. Sawley

    Introduction More than seventy CMS collaborators attended the Computing and Offline Workshop in San Diego, California, April 20-24th to discuss the state of readiness of software and computing for collisions. Focus and priority were given to preparations for data taking and providing room for ample dialog between groups involved in Commissioning, Data Operations, Analysis and MC Production. Throughout the workshop, aspects of software, operating procedures and issues addressing all parts of the computing model were discussed. Plans for the CMS participation in STEP’09, the combined scale testing for all four experiments due in June 2009, were refined. The article in CMS Times by Frank Wuerthwein gave a good recap of the highly collaborative atmosphere of the workshop. Many thanks to UCSD and to the organizers for taking care of this workshop, which resulted in a long list of action items and was definitely a success. A considerable amount of effort and care is invested in the estimate of the comput...

  4. COMPUTING

    CERN Multimedia

    I. Fisk

    2010-01-01

    Introduction It has been a very active quarter in Computing with interesting progress in all areas. The activity level at the computing facilities, driven by both organised processing from data operations and user analysis, has been steadily increasing. The large-scale production of simulated events that has been progressing throughout the fall is wrapping-up and reprocessing with pile-up will continue. A large reprocessing of all the proton-proton data has just been released and another will follow shortly. The number of analysis jobs by users each day, that was already hitting the computing model expectations at the time of ICHEP, is now 33% higher. We are expecting a busy holiday break to ensure samples are ready in time for the winter conferences. Heavy Ion An activity that is still in progress is computing for the heavy-ion program. The heavy-ion events are collected without zero suppression, so the event size is much large at roughly 11 MB per event of RAW. The central collisions are more complex and...

  5. The role of 18F-fluoro-2-deoxyglucose positron emission tomography/computed tomography in the management of patients with carcinoma of unknown primary.

    Science.gov (United States)

    Deonarine, P; Han, S; Poon, F W; de Wet, C

    2013-08-01

    Carcinoma of unknown primary is one of the ten most frequent cancers worldwide. Its median survival time is less than 10 months. Detecting primary tumour locations and/or occult metastatic lesions may inform definitive treatment and improve patients' prognosis. We aimed to determine: (1) the sensitivity, specificity and accuracy of (18)F-fluoro-2-deoxyglucose positron emission tomography/computed tomography; (2) its detection rate of primary tumour locations and occult metastases and (3) factors associated with improved survival times. We retrospectively reviewed all cases in the West of Scotland for the period 1 December 2007 to 31 May 2011 that met all our selection criteria: (1) diagnosis of carcinoma of unknown primary; (2) a thorough but negative 'work-up' and (3) (18)F-fluoro-2-deoxyglucose positron emission tomography/computed tomography report. Statistical methods included frequencies, Kaplan-Meier graphs and log-rank tests to compare survival times. (18)F-fluoro-2-deoxyglucose positron emission tomography/computed tomography detected primary tumour sites in 19/51 (37.3%) and occult metastases in 28/51 (54.9%) of eligible patients. Its sensitivity, specificity and accuracy were 79.2%, 70.4% and 74.5%, respectively; 20/51 (39.2%) patients died during the study period with a median survival of 8.4 months (range 21.4, SD ± 6.2). The number of metastatic locations was strongly associated with survival (p = 0.002), but detection of a primary tumour site (p = 0.174) or histopathology (p = 0.301) was not. (18)F-fluoro-2-deoxyglucose positron emission tomography/computed tomography detected occult metastatic sites in the majority and a primary cancer location in a substantial minority of patients. Our results were comparable with international literature and may indicate that (18)F-fluoro-2-deoxyglucose positron emission tomography/computed tomography have an early role to improve the accuracy of cancer staging and to optimise carcinoma of unknown

  6. Coronary-to-pulmonary artery fistula in adults: Evaluation with thallium-201 myocardial perfusion SPECT.

    Directory of Open Access Journals (Sweden)

    Seul Ki Lee

    Full Text Available With the increasing use of multi-detector CT, the number of detected cases with coronary-to-pulmonary artery fistula (CPAF has increased. Several previous studies reported severe cases of angina, but no appropriate tests to evaluate myocardial perfusion for patients with CPAF have been established. We evaluated the hemodynamic characteristics of CPAF using thallium-201 (Tl-201 single photon emission computed tomography (SPECT.Tl-201 SPECT was performed in 17 patients with CPAF, but without evidence of coronary artery disease on coronary computed tomography angiography (CCTA (age, 58.5±13.3 years; 8 men. Quantitative analysis of scintigraphic data was performed. Additionally, perfusion abnormalities were compared with CCTA findings. Medical records were obtained to define clinical data, diagnostic findings, symptoms, management, follow-up data, and major adverse cardiac events (MACE.Six patients (35.2% showed perfusion abnormalities on SPECT studies and could be classified as follows: 3 patients, no reversible ischemia (3/17, 17.6%; 1 patient, mild ischemia (1/17, 5.8%; and 2 patients, moderate ischemia (2/17, 11.7%. During the follow-up, ten patients (58.8% improved under medical management and 5 patients (29.4% underwent surgical ligation for CPAF with symptomatic improvement in 4 patients. Seven patients performed follow-up myocardial perfusion SPECT, and symptomatic improvement correlated well with scintigraphic perfusion improvement in 6 patients No MACE was observed.Tl-201 myocardial perfusion SPECT might be useful for determining the hemodynamic status and for risk stratification in patients with CPAF.

  7. The value of scintigraphy, computed tomography, magnetic resonance imaging, and single-photon emission computed tomography/computed tomography for the diagnosis of ectopic thyroid in the head and neck: A STROBE-compliant retrospective study.

    Science.gov (United States)

    Xu, Feng; Shao, Ziyang; Yang, Gongxing; Gu, Aichun; Jiang, Mengda; Pan, Yifan; Ma, Yubo

    2018-03-01

    Because of its rarity, the exact imaging features of ectopic thyroid are poorly known.To analyze the value of scintigraphy, computed tomography (CT), magnetic resonance imaging (MRI), and single-photon emission computed tomography (SPECT)/CT in the diagnosis of ectopic thyroid in the head and neck.First, we retrospectively analyzed the scintigraphy, CT, MRI, and SPECT/CT images from 25 masses (22 patients) suspected of head and neck ectopic thyroid from 2006 to 2017 at the Shanghai Ninth People's Hospital. Each mass was imaged by nuclear imaging (scintigraphy with or without SPECT/CT) and radiological exam (CT and/or MRI). Pathological examination was considered as the gold standard. Secondly, thirteen malignant ectopic thyroids in the head and neck reported in the English literature from 2001 to 2017 were retrieved for comparison.The accuracy of scintigraphy was not significantly higher than that of CT (94.7%, vs 89.5%, P > .99) or MRI (92.3%, vs 84.6%, P > .99). Five masses which underwent scintigraphy with SPECT/CT were all true positive, while 1 was false negative on MRI, and 2 were false negative on CT. Compared to the benign ectopic thyroids in our study, the 13 malignant ectopic thyroids retrieved from the literature were grossly the same in shape, margins, and invasion on CT or MRI.The number of patients was limited, but scintigraphy combined with SPECT/CT could be a reliable method for the diagnosis of ectopic thyroid. Benign and malignant ectopic thyroids appear to be similar in shapes, margins, and invasion on CT or MRI.

  8. Is a positron emission tomography-computed tomography scan useful in the staging of thymic epithelial neoplasms?

    Science.gov (United States)

    Viti, Andrea; Terzi, Alberto; Bianchi, Andrea; Bertolaccini, Luca

    2014-07-01

    A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed concerned the employment of 18-fluorine fluorodeoxyglucose positron emission tomography/computed tomography (PET-CT) in the preoperative evaluation of thymic epithelial neoplasms (TENs). We reviewed its role as a predictor of Masaoka stage and histology (according to the WHO). In clinical practice, stage is considered the most important determinant in the therapeutic approach. A total of 265 papers were found as a result of the reported search, of which 14 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. All the studies are retrospective analyses. Patient numbers varied from 13 to 58. Our research showed that PET-CT could clearly add information about the histology of the tumour. Thymic carcinoma constantly showed a higher standard uptake value (SUVmax) than thymomas. Furthermore, in one retrospective study of 36 patients, when using a derived PET indicator, the T/M ratio (ratio between SUVmax of the tumour and SUVmax of mediastinum, as conventionally measured at the level of the aortic arc), PET-CT could also differentiate between low- and high-risk thymomas (low risk vs high risk P = 0.01). In another study, a cut-off value of T/M ratio of 2.75 was identified between low- and high-risk TENs. The role of PET-CT in prediction of stage is harder to recognize. In one study, there was a statistically significant correlation between SUVmax, T/M ratio and Masaoka stage (P = 0.781 and 0.718, respectively). When analysing the data from the three larger series on this topic (58, 51 and 47 patients, the latter group selected in a multicentre study), only one study identified a correlation between SUVmax and Masaoka stage (Spearman correlation coefficient 0.30, P = 0.0436), while the other two failed

  9. Prevalence of detecting unknown cerebral metastases in fluorodeoxyglucose positron emission tomography/computed tomography and its potential clinical impact.

    Science.gov (United States)

    Kung, Boom Ting; Auyong, T K; Tong, C M

    2014-05-01

    To determine the prevalence of incidental finding of unknown cerebral metastases and explore the clinical impact of detecting unknown brain metastases among individuals underwent whole body fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) with brain included in field of view. A retrospective review of 1876 patients who underwent whole body PET/CT examination in our clinical PET center for oncological evaluation from January 2009 to September 2009 was performed. The total number and prevalence of unknown brain metastases detected by PET/CT were calculated. Patients diagnosed with cerebral metastases by PET/CT were further analyzed via the electronic patient record system for relevant clinical and radiological findings. Positive predictive value of PET/CT for the diagnosis of cerebral metastases was calculated with reference to contrast enhanced magnetic resonance imaging (MRI) or contrast enhanced CT. Of the 1876 subjects, 71 patients (3.8%) were diagnosed with cerebral metastases by PET/CT. 31 patients were already diagnosed with brain metastases before PET/CT. Among the 40 patients with unknown brain metastasis, 24 (60.0%) underwent either MRI (n = 5) or CT (n = 19) after PET/CT, of which 17 patients were confirmed with cerebral metastases. The true positive rate was 70.8% (17/24), while the false positive rate of PET/CT was 29.2% (7/24). Nearly 94.1% (16/17) patients with confirmed cerebral metastases on MRI or CT had subsequent change in management. Among the remaining 16 patients with positive findings of cerebral metastases without further radiological correlation, 43.8% (7/16) patients had change in management after PET/CT. A total of 57.5% (23/40) patients had change in management after PET/CT. The point prevalence of detecting unknown cerebral metastases by PET/CT was 2.1% (40/1876). 94.1% patients with newly diagnosed brain metastases confirmed with either MRI or CT received immediate treatment for cerebral

  10. Pretreatment Staging Positron Emission Tomography/Computed Tomography in Patients With Inflammatory Breast Cancer Influences Radiation Treatment Field Designs

    International Nuclear Information System (INIS)

    Walker, Gary V.; Niikura, Naoki; Yang Wei; Rohren, Eric; Valero, Vicente; Woodward, Wendy A.; Alvarez, Ricardo H.; Lucci, Anthony; Ueno, Naoto T.; Buchholz, Thomas A.

    2012-01-01

    Purpose: Positron emission tomography/computed tomography (PET/CT) is increasingly being utilized for staging of inflammatory breast cancer (IBC). The purpose of this study was to define how pretreatment PET/CT studies affected postmastectomy radiation treatment (PMRT) planning decisions for IBC. Methods and Materials: We performed a retrospective analysis of 62 patients diagnosed with IBC between 2004 and 2009, who were treated with PMRT in our institution and who had a staging PET/CT within 3 months of diagnosis. Patients received a baseline physical examination, staging mammography, ultrasonographic examination of breast and draining lymphatics, and chest radiography; most patients also had a bone scan (55 patients), liver imaging (52 patients), breast MRI (46 patients), and chest CT (25 patients). We compared how PET/CT findings affected PMRT, assuming that standard PMRT would target the chest wall, level III axilla, supraclavicular fossa, and internal mammary chain (IMC). Any modification of target volumes, field borders, or dose prescriptions was considered a change. Results: PET/CT detected new areas of disease in 27 of the 62 patients (44%). The areas of additional disease included the breast (1 patient), ipsilateral axilla (1 patient), ipsilateral supraclavicular (4 patients), ipsilateral infraclavicular (1 patient), ipsilateral IMC (5 patients), ipsilateral subpectoral (3 patients), mediastinal (8 patients), other distant/contralateral lymph nodes (15 patients), or bone (6 patients). One patient was found to have a non-breast second primary tumor. The findings of the PET/CT led to changes in PMRT in 11 of 62 patients (17.7%). These changes included additional fields in 5 patients, adjustment of fields in 2 patients, and higher doses to the supraclavicular fossa (2 patients) and IMC (5 patients). Conclusions: For patients with newly diagnosed IBC, pretreatment PET/CT provides important information concerning involvement of locoregional lymph nodes

  11. Improving appropriate use of echocardiography and single-photon emission computed tomographic myocardial perfusion imaging: a continuous quality improvement initiative.

    Science.gov (United States)

    Johnson, Thomas V; Rose, Geoffrey A; Fenner, Deborah J; Rozario, Nigel L

    2014-07-01

    Appropriate use criteria for cardiovascular imaging have been published, but compliance in practice has been incomplete, with persistent high rates of inappropriate use. The aim of this study was to show the efficacy of a continuous quality improvement (CQI) initiative to favorably influence the appropriate use of outpatient transthoracic echocardiography and single-photon emission computed tomographic (SPECT) myocardial perfusion imaging (MPI) in a large cardiovascular practice. In this prospective study, a multiphase CQI initiative was implemented, and its impact on ordering patterns for outpatient transthoracic echocardiography and SPECT MPI was assessed. Between November and December 2010, a baseline analysis of the application of appropriate use criteria to indications for outpatient transthoracic echocardiographic studies (n = 203) and SPECT MPI studies (n = 205) was performed, with studies categorized as "appropriate," "inappropriate," "uncertain," or "unclassified." The CQI initiative was then begun, with (1) clinician education, including didactic lectures and case-based presentations with audience participation; (2) system changes in ordering processes, with redesigned image ordering forms; and (3) peer review and feedback. A follow-up analysis was then performed between June and August 2012, with categorization of indications for transthoracic echocardiographic studies (n = 206) and SPECT MPI studies (n = 206). At baseline, 73.9% of echocardiographic studies were categorized as appropriate, 16.7% as inappropriate, 5.9% as uncertain, and 3.4% as unclassified. Similarly, for SPECT MPI studies 71.7% were categorized as appropriate, 18.5% as inappropriate, 7.8% as uncertain, and 1.9% as unclassified. Separate analysis of the two most important categories, appropriate and inappropriate, demonstrated a significant improvement after the CQI initiative, with a 63% reduction in inappropriate echocardiographic studies (18.5% vs 6.9%, P = .0010) and a 46% reduction

  12. Clinical evaluation of reducing acquisition time on single-photon emission computed tomography image quality using proprietary resolution recovery software.

    Science.gov (United States)

    Aldridge, Matthew D; Waddington, Wendy W; Dickson, John C; Prakash, Vineet; Ell, Peter J; Bomanji, Jamshed B

    2013-11-01

    A three-dimensional model-based resolution recovery (RR) reconstruction algorithm that compensates for collimator-detector response, resulting in an improvement in reconstructed spatial resolution and signal-to-noise ratio of single-photon emission computed tomography (SPECT) images, was tested. The software is said to retain image quality even with reduced acquisition time. Clinically, any improvement in patient throughput without loss of quality is to be welcomed. Furthermore, future restrictions in radiotracer supplies may add value to this type of data analysis. The aims of this study were to assess improvement in image quality using the software and to evaluate the potential of performing reduced time acquisitions for bone and parathyroid SPECT applications. Data acquisition was performed using the local standard SPECT/CT protocols for 99mTc-hydroxymethylene diphosphonate bone and 99mTc-methoxyisobutylisonitrile parathyroid SPECT imaging. The principal modification applied was the acquisition of an eight-frame gated data set acquired using an ECG simulator with a fixed signal as the trigger. This had the effect of partitioning the data such that the effect of reduced time acquisitions could be assessed without conferring additional scanning time on the patient. The set of summed data sets was then independently reconstructed using the RR software to permit a blinded assessment of the effect of acquired counts upon reconstructed image quality as adjudged by three experienced observers. Data sets reconstructed with the RR software were compared with the local standard processing protocols; filtered back-projection and ordered-subset expectation-maximization. Thirty SPECT studies were assessed (20 bone and 10 parathyroid). The images reconstructed with the RR algorithm showed improved image quality for both full-time and half-time acquisitions over local current processing protocols (Pquality compared with local processing protocols and has been introduced into

  13. COMPUTING

    CERN Multimedia

    P. McBride

    It has been a very active year for the computing project with strong contributions from members of the global community. The project has focused on site preparation and Monte Carlo production. The operations group has begun processing data from P5 as part of the global data commissioning. Improvements in transfer rates and site availability have been seen as computing sites across the globe prepare for large scale production and analysis as part of CSA07. Preparations for the upcoming Computing Software and Analysis Challenge CSA07 are progressing. Ian Fisk and Neil Geddes have been appointed as coordinators for the challenge. CSA07 will include production tests of the Tier-0 production system, reprocessing at the Tier-1 sites and Monte Carlo production at the Tier-2 sites. At the same time there will be a large analysis exercise at the Tier-2 centres. Pre-production simulation of the Monte Carlo events for the challenge is beginning. Scale tests of the Tier-0 will begin in mid-July and the challenge it...

  14. COMPUTING

    CERN Multimedia

    M. Kasemann

    CCRC’08 challenges and CSA08 During the February campaign of the Common Computing readiness challenges (CCRC’08), the CMS computing team had achieved very good results. The link between the detector site and the Tier0 was tested by gradually increasing the number of parallel transfer streams well beyond the target. Tests covered the global robustness at the Tier0, processing a massive number of very large files and with a high writing speed to tapes.  Other tests covered the links between the different Tiers of the distributed infrastructure and the pre-staging and reprocessing capacity of the Tier1’s: response time, data transfer rate and success rate for Tape to Buffer staging of files kept exclusively on Tape were measured. In all cases, coordination with the sites was efficient and no serious problem was found. These successful preparations prepared the ground for the second phase of the CCRC’08 campaign, in May. The Computing Software and Analysis challen...

  15. COMPUTING

    CERN Multimedia

    I. Fisk

    2011-01-01

    Introduction It has been a very active quarter in Computing with interesting progress in all areas. The activity level at the computing facilities, driven by both organised processing from data operations and user analysis, has been steadily increasing. The large-scale production of simulated events that has been progressing throughout the fall is wrapping-up and reprocessing with pile-up will continue. A large reprocessing of all the proton-proton data has just been released and another will follow shortly. The number of analysis jobs by users each day, that was already hitting the computing model expectations at the time of ICHEP, is now 33% higher. We are expecting a busy holiday break to ensure samples are ready in time for the winter conferences. Heavy Ion The Tier 0 infrastructure was able to repack and promptly reconstruct heavy-ion collision data. Two copies were made of the data at CERN using a large CASTOR disk pool, and the core physics sample was replicated ...

  16. COMPUTING

    CERN Multimedia

    M. Kasemann

    Introduction More than seventy CMS collaborators attended the Computing and Offline Workshop in San Diego, California, April 20-24th to discuss the state of readiness of software and computing for collisions. Focus and priority were given to preparations for data taking and providing room for ample dialog between groups involved in Commissioning, Data Operations, Analysis and MC Production. Throughout the workshop, aspects of software, operating procedures and issues addressing all parts of the computing model were discussed. Plans for the CMS participation in STEP’09, the combined scale testing for all four experiments due in June 2009, were refined. The article in CMS Times by Frank Wuerthwein gave a good recap of the highly collaborative atmosphere of the workshop. Many thanks to UCSD and to the organizers for taking care of this workshop, which resulted in a long list of action items and was definitely a success. A considerable amount of effort and care is invested in the estimate of the co...

  17. COMPUTING

    CERN Multimedia

    I. Fisk

    2012-01-01

    Introduction Computing continued with a high level of activity over the winter in preparation for conferences and the start of the 2012 run. 2012 brings new challenges with a new energy, more complex events, and the need to make the best use of the available time before the Long Shutdown. We expect to be resource constrained on all tiers of the computing system in 2012 and are working to ensure the high-priority goals of CMS are not impacted. Heavy ions After a successful 2011 heavy-ion run, the programme is moving to analysis. During the run, the CAF resources were well used for prompt analysis. Since then in 2012 on average 200 job slots have been used continuously at Vanderbilt for analysis workflows. Operations Office As of 2012, the Computing Project emphasis has moved from commissioning to operation of the various systems. This is reflected in the new organisation structure where the Facilities and Data Operations tasks have been merged into a common Operations Office, which now covers everything ...

  18. COMPUTING

    CERN Multimedia

    M. Kasemann

    Introduction During the past six months, Computing participated in the STEP09 exercise, had a major involvement in the October exercise and has been working with CMS sites on improving open issues relevant for data taking. At the same time operations for MC production, real data reconstruction and re-reconstructions and data transfers at large scales were performed. STEP09 was successfully conducted in June as a joint exercise with ATLAS and the other experiments. It gave good indication about the readiness of the WLCG infrastructure with the two major LHC experiments stressing the reading, writing and processing of physics data. The October Exercise, in contrast, was conducted as an all-CMS exercise, where Physics, Computing and Offline worked on a common plan to exercise all steps to efficiently access and analyze data. As one of the major results, the CMS Tier-2s demonstrated to be fully capable for performing data analysis. In recent weeks, efforts were devoted to CMS Computing readiness. All th...

  19. COMPUTING

    CERN Multimedia

    I. Fisk

    2010-01-01

    Introduction The first data taking period of November produced a first scientific paper, and this is a very satisfactory step for Computing. It also gave the invaluable opportunity to learn and debrief from this first, intense period, and make the necessary adaptations. The alarm procedures between different groups (DAQ, Physics, T0 processing, Alignment/calibration, T1 and T2 communications) have been reinforced. A major effort has also been invested into remodeling and optimizing operator tasks in all activities in Computing, in parallel with the recruitment of new Cat A operators. The teams are being completed and by mid year the new tasks will have been assigned. CRB (Computing Resource Board) The Board met twice since last CMS week. In December it reviewed the experience of the November data-taking period and could measure the positive improvements made for the site readiness. It also reviewed the policy under which Tier-2 are associated with Physics Groups. Such associations are decided twice per ye...

  20. COMPUTING

    CERN Multimedia

    Matthias Kasemann

    Overview The main focus during the summer was to handle data coming from the detector and to perform Monte Carlo production. The lessons learned during the CCRC and CSA08 challenges in May were addressed by dedicated PADA campaigns lead by the Integration team. Big improvements were achieved in the stability and reliability of the CMS Tier1 and Tier2 centres by regular and systematic follow-up of faults and errors with the help of the Savannah bug tracking system. In preparation for data taking the roles of a Computing Run Coordinator and regular computing shifts monitoring the services and infrastructure as well as interfacing to the data operations tasks are being defined. The shift plan until the end of 2008 is being put together. User support worked on documentation and organized several training sessions. The ECoM task force delivered the report on “Use Cases for Start-up of pp Data-Taking” with recommendations and a set of tests to be performed for trigger rates much higher than the ...

  1. COMPUTING

    CERN Multimedia

    P. MacBride

    The Computing Software and Analysis Challenge CSA07 has been the main focus of the Computing Project for the past few months. Activities began over the summer with the preparation of the Monte Carlo data sets for the challenge and tests of the new production system at the Tier-0 at CERN. The pre-challenge Monte Carlo production was done in several steps: physics generation, detector simulation, digitization, conversion to RAW format and the samples were run through the High Level Trigger (HLT). The data was then merged into three "Soups": Chowder (ALPGEN), Stew (Filtered Pythia) and Gumbo (Pythia). The challenge officially started when the first Chowder events were reconstructed on the Tier-0 on October 3rd. The data operations teams were very busy during the the challenge period. The MC production teams continued with signal production and processing while the Tier-0 and Tier-1 teams worked on splitting the Soups into Primary Data Sets (PDS), reconstruction and skimming. The storage sys...

  2. COMPUTING

    CERN Document Server

    2010-01-01

    Introduction Just two months after the “LHC First Physics” event of 30th March, the analysis of the O(200) million 7 TeV collision events in CMS accumulated during the first 60 days is well under way. The consistency of the CMS computing model has been confirmed during these first weeks of data taking. This model is based on a hierarchy of use-cases deployed between the different tiers and, in particular, the distribution of RECO data to T1s, who then serve data on request to T2s, along a topology known as “fat tree”. Indeed, during this period this model was further extended by almost full “mesh” commissioning, meaning that RECO data were shipped to T2s whenever possible, enabling additional physics analyses compared with the “fat tree” model. Computing activities at the CMS Analysis Facility (CAF) have been marked by a good time response for a load almost evenly shared between ALCA (Alignment and Calibration tasks - highest p...

  3. COMPUTING

    CERN Multimedia

    I. Fisk

    2013-01-01

    Computing operation has been lower as the Run 1 samples are completing and smaller samples for upgrades and preparations are ramping up. Much of the computing activity is focusing on preparations for Run 2 and improvements in data access and flexibility of using resources. Operations Office Data processing was slow in the second half of 2013 with only the legacy re-reconstruction pass of 2011 data being processed at the sites.   Figure 1: MC production and processing was more in demand with a peak of over 750 Million GEN-SIM events in a single month.   Figure 2: The transfer system worked reliably and efficiently and transferred on average close to 520 TB per week with peaks at close to 1.2 PB.   Figure 3: The volume of data moved between CMS sites in the last six months   The tape utilisation was a focus for the operation teams with frequent deletion campaigns from deprecated 7 TeV MC GEN-SIM samples to INVALID datasets, which could be cleaned up...

  4. COMPUTING

    CERN Multimedia

    I. Fisk

    2012-01-01

      Introduction Computing activity has been running at a sustained, high rate as we collect data at high luminosity, process simulation, and begin to process the parked data. The system is functional, though a number of improvements are planned during LS1. Many of the changes will impact users, we hope only in positive ways. We are trying to improve the distributed analysis tools as well as the ability to access more data samples more transparently.  Operations Office Figure 2: Number of events per month, for 2012 Since the June CMS Week, Computing Operations teams successfully completed data re-reconstruction passes and finished the CMSSW_53X MC campaign with over three billion events available in AOD format. Recorded data was successfully processed in parallel, exceeding 1.2 billion raw physics events per month for the first time in October 2012 due to the increase in data-parking rate. In parallel, large efforts were dedicated to WMAgent development and integrati...

  5. COMPUTING

    CERN Multimedia

    M. Kasemann

    Introduction A large fraction of the effort was focused during the last period into the preparation and monitoring of the February tests of Common VO Computing Readiness Challenge 08. CCRC08 is being run by the WLCG collaboration in two phases, between the centres and all experiments. The February test is dedicated to functionality tests, while the May challenge will consist of running at all centres and with full workflows. For this first period, a number of functionality checks of the computing power, data repositories and archives as well as network links are planned. This will help assess the reliability of the systems under a variety of loads, and identifying possible bottlenecks. Many tests are scheduled together with other VOs, allowing the full scale stress test. The data rates (writing, accessing and transfer¬ring) are being checked under a variety of loads and operating conditions, as well as the reliability and transfer rates of the links between Tier-0 and Tier-1s. In addition, the capa...

  6. COMPUTING

    CERN Multimedia

    Contributions from I. Fisk

    2012-01-01

    Introduction The start of the 2012 run has been busy for Computing. We have reconstructed, archived, and served a larger sample of new data than in 2011, and we are in the process of producing an even larger new sample of simulations at 8 TeV. The running conditions and system performance are largely what was anticipated in the plan, thanks to the hard work and preparation of many people. Heavy ions Heavy Ions has been actively analysing data and preparing for conferences.  Operations Office Figure 6: Transfers from all sites in the last 90 days For ICHEP and the Upgrade efforts, we needed to produce and process record amounts of MC samples while supporting the very successful data-taking. This was a large burden, especially on the team members. Nevertheless the last three months were very successful and the total output was phenomenal, thanks to our dedicated site admins who keep the sites operational and the computing project members who spend countless hours nursing the...

  7. Optimization of pinhole single photon emission computed tomography (pinhole SPECT) reconstruction; Optimisation de la reconstruction en tomographie d'emission monophotonique avec colimateur stenope

    Energy Technology Data Exchange (ETDEWEB)

    Israel-Jost, V

    2006-11-15

    In SPECT small animal imaging, it is highly recommended to accurately model the response of the detector in order to improve the low spatial resolution. The volume to reconstruct is thus obtained both by back-projecting and de-convolving the projections. We chose iterative methods, which permit one to solve the inverse problem independently from the model's complexity. We describe in this work a Gaussian model of point spread function (PSF) whose position, width and maximum are computed according to physical and geometrical parameters. Then we use the rotation symmetry to replace the computation of P projection operators, each one corresponding to one position of the detector around the object, by the computation of only one of them. This is achieved by choosing an appropriate polar discretization, for which we control the angular density of voxels to avoid over-sampling the center of the field of view. Finally, we propose a new family of algorithms, the so-called frequency adapted algorithms, which enable to optimize the reconstruction of a given band in the frequency domain on both the speed of convergence and the quality of the image. (author)

  8. COMPUTING

    CERN Multimedia

    I. Fisk

    2011-01-01

    Introduction The Computing Team successfully completed the storage, initial processing, and distribution for analysis of proton-proton data in 2011. There are still a variety of activities ongoing to support winter conference activities and preparations for 2012. Heavy ions The heavy-ion run for 2011 started in early November and has already demonstrated good machine performance and success of some of the more advanced workflows planned for 2011. Data collection will continue until early December. Facilities and Infrastructure Operations Operational and deployment support for WMAgent and WorkQueue+Request Manager components, routinely used in production by Data Operations, are provided. The GlideInWMS and components installation are now deployed at CERN, which is added to the GlideInWMS factory placed in the US. There has been new operational collaboration between the CERN team and the UCSD GlideIn factory operators, covering each others time zones by monitoring/debugging pilot jobs sent from the facto...

  9. Neutron stimulated emission computed tomography applied to the assessment of calcium deposition due to the presence of microcalcifications associated with breast cancer

    International Nuclear Information System (INIS)

    Viana, Rodrigo S.S.; Yoriyaz, Helio

    2011-01-01

    In this paper we presented an application of the Neutron Stimulated Emission Computed Tomography (NSECT), which uses a thin beam of fast neutrons to stimulate stable nuclei in a sample, emitting characteristic gamma radiation. The photon energy is unique and it is used to identify the emitting nuclei. This technique was applied for evaluating the calcium isotopic composition changing due to the development of breast microcalcifications. A particular situation was simulated in which clustered microcalcifications were modeled with diameters less than 1.40 mm. In this case, neutron beam breast spectroscopy was successful in detecting the counting changes in the photon emission spectra for energies, which are characteristics of 4 0C a isotope in a low deposited dose rate. (author)

  10. Regional cerebral blood flow single photon emission computed tomography for detection of Frontotemporal dementia in people with suspected dementia.

    Science.gov (United States)

    Archer, Hilary A; Smailagic, Nadja; John, Christeena; Holmes, Robin B; Takwoingi, Yemisi; Coulthard, Elizabeth J; Cullum, Sarah

    2015-06-23

    In the UK, dementia affects 5% of the population aged over 65 years and 25% of those over 85 years. Frontotemporal dementia (FTD) represents one subtype and is thought to account for up to 16% of all degenerative dementias. Although the core of the diagnostic process in dementia rests firmly on clinical and cognitive assessments, a wide range of investigations are available to aid diagnosis.Regional cerebral blood flow (rCBF) single-photon emission computed tomography (SPECT) is an established clinical tool that uses an intravenously injected radiolabelled tracer to map blood flow in the brain. In FTD the characteristic pattern seen is hypoperfusion of the frontal and anterior temporal lobes. This pattern of blood flow is different to patterns seen in other subtypes of dementia and so can be used to differentiate FTD.It has been proposed that a diagnosis of FTD, (particularly early stage), should be made not only on the basis of clinical criteria but using a combination of other diagnostic findings, including rCBF SPECT. However, more extensive testing comes at a financial cost, and with a potential risk to patient safety and comfort. To determine the diagnostic accuracy of rCBF SPECT for diagnosing FTD in populations with suspected dementia in secondary/tertiary healthcare settings and in the differential diagnosis of FTD from other dementia subtypes. Our search strategy used two concepts: (a) the index test and (b) the condition of interest. We searched citation databases, including MEDLINE (Ovid SP), EMBASE (Ovid SP), BIOSIS (Ovid SP), Web of Science Core Collection (ISI Web of Science), PsycINFO (Ovid SP), CINAHL (EBSCOhost) and LILACS (Bireme), using structured search strategies appropriate for each database. In addition we searched specialised sources of diagnostic test accuracy studies and reviews including: MEDION (Universities of Maastricht and Leuven), DARE (Database of Abstracts of Reviews of Effects) and HTA (Health Technology Assessment) database

  11. Influence of 18F-fluorodeoxyglucose-positron emission tomography on computed tomography-based radiation treatment planning for oesophageal cancer

    International Nuclear Information System (INIS)

    Everitt, C.; Leong, T.

    2006-01-01

    The addition of positron emission tomography (PET) information to CT-based radiotherapy treatment planning has the potential to improve target volume definition through more accurate localization of the primary tumour and involved regional lymph nodes. This case report describes the first patient enrolled to a prospective study evaluating the effects of coregistered positron emission tomography/CT images on radiotherapy treatment planning for oesophageal cancer. The results show that if combined positron emission tomography/CT is used for radiotherapy treatment planning, there may be alterations to the delineation of tumour volumes when compared to CT alone. For this patient, a geographic miss of tumour would have occurred if CT data alone were used for radiotherapy planning Copyright (2006) Blackwell Publishing Asia Pty Ltd

  12. [Ambient air pollution in the city of Irkutsk by emissions from mobile sources (the use of the computational method)].

    Science.gov (United States)

    Iakovenko, O N; Kravchenko, N A

    2015-01-01

    In the article there are presented the results of calculations of a number of emissions of pollutants from motor vehicles in two districts of the city of Irkutsk. It was revealed that with the change in the structure and intensity of road traffic flows on highways of the city, there is altered the composition and quantity of pollutant emissions, tropic to the respiratory system of the human body. That is of great importance, because in the city of Irkutsk the rate of morbidity and mortality from respiratory diseases is higher than in average in Russia.

  13. Three-Dimensional Image Fusion of 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography and Contrast-Enhanced Computed Tomography for Computer-Assisted Planning of Maxillectomy of Recurrent Maxillary Squamous Cell Carcinoma and Defect Reconstruction.

    Science.gov (United States)

    Yu, Yao; Zhang, Wen-Bo; Liu, Xiao-Jing; Guo, Chuan-Bin; Yu, Guang-Yan; Peng, Xin

    2017-06-01

    The purpose of this study was to describe new technology assisted by 3-dimensional (3D) image fusion of 18 F-fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) and contrast-enhanced CT (CECT) for computer planning of a maxillectomy of recurrent maxillary squamous cell carcinoma and defect reconstruction. Treatment of recurrent maxillary squamous cell carcinoma usually includes tumor resection and free flap reconstruction. FDG-PET/CT provided images of regions of abnormal glucose uptake and thus showed metabolic tumor volume to guide tumor resection. CECT data were used to create 3D reconstructed images of vessels to show the vascular diameters and locations, so that the most suitable vein and artery could be selected during anastomosis of the free flap. The data from preoperative maxillofacial CECT scans and FDG-PET/CT imaging were imported into the navigation system (iPlan 3.0; Brainlab, Feldkirchen, Germany). Three-dimensional image fusion between FDG-PET/CT and CECT was accomplished using Brainlab software according to the position of the 2 skulls simulated in the CECT image and PET/CT image, respectively. After verification of the image fusion accuracy, the 3D reconstruction images of the metabolic tumor, vessels, and other critical structures could be visualized within the same coordinate system. These sagittal, coronal, axial, and 3D reconstruction images were used to determine the virtual osteotomy sites and reconstruction plan, which was provided to the surgeon and used for surgical navigation. The average shift of the 3D image fusion between FDG-PET/CT and CECT was less than 1 mm. This technique, by clearly showing the metabolic tumor volume and the most suitable vessels for anastomosis, facilitated resection and reconstruction of recurrent maxillary squamous cell carcinoma. We used 3D image fusion of FDG-PET/CT and CECT to successfully accomplish resection and reconstruction of recurrent maxillary squamous cell carcinoma

  14. Predicting the neural effect of switching from donepezil to galantamine based on single-photon emission computed tomography findings in patients with Alzheimer's disease.

    Science.gov (United States)

    Oka, Mizuki; Nakaaki, Shutaro; Negi, Atsushi; Miyata, Jun; Nakagawa, Atsuo; Hirono, Nobutsugu; Mimura, Masaru

    2016-03-01

    A number of neuroimaging studies have addressed the specific effect of treatment with cholinesterase inhibitors on the frontal lobe in patients with Alzheimer's disease (AD). However, the neural effects of cholinesterase inhibitors on both apathy and executive dysfunction remain unclear. We examined whether baseline regional cerebral blood flow, as determined by using single-photon emission computed tomography, is capable of predicting changes in apathy and executive dysfunction in response to AD patients switching from donepezil to galantamine therapy. We conducted a 24-week, prospective, open-label study of AD patients treated with galantamine who did not respond to previous treatment with donepezil. Single-photon emission computed tomography was performed at baseline, and behaviour and cognitive assessments including the Mini-Mental State Examination, the Japanese version of the Alzheimer's Disease Assessment Scale-cognitive subscale, the Frontal Assessment Battery, the Neuropsychiatry Inventory Brief Questionnaire Form, and the Dysexecutive Questionnaire were conducted at three time points (baseline and after 12 and 24 weeks of galantamine therapy). After galantamine therapy, the Neuropsychiatry Inventory Brief Questionnaire Form scores (apathy, irritability, and aberrant motor symptoms) and the Dysexecutive Questionnaire score improved significantly. The single-photon emission computed tomography findings showed that lower baseline regional cerebral blood flow values in several frontal areas, including the dorsolateral and ventrolateral prefrontal cortex, the anterior cingulate, and the orbitofrontal cortex, predicted greater reductions in the score for apathy (distress) on the Neuropsychiatry Inventory Brief Questionnaire Form and the Dysexecutive Questionnaire score after patients switched from donepezil to galantamine therapy. Our study suggests that galantamine therapy, unlike donepezil, is characterized by a dual mechanism of action that may increase

  15. An evaluation of an improved method for computing histograms in dynamic tracer studies using positron-emission tomography

    International Nuclear Information System (INIS)

    Ollinger, J.M.; Snyder, D.L.

    1986-01-01

    A method for computing approximate minimum-mean-square-error estimates of histograms from list-mode data for use in dynamic tracer studies is evaluated. Parameters estimated from these histograms are significantly more accurate than those estimated from histograms computed by a commonly used method

  16. COMPUTING

    CERN Multimedia

    M. Kasemann

    CMS relies on a well functioning, distributed computing infrastructure. The Site Availability Monitoring (SAM) and the Job Robot submission have been very instrumental for site commissioning in order to increase availability of more sites such that they are available to participate in CSA07 and are ready to be used for analysis. The commissioning process has been further developed, including "lessons learned" documentation via the CMS twiki. Recently the visualization, presentation and summarizing of SAM tests for sites has been redesigned, it is now developed by the central ARDA project of WLCG. Work to test the new gLite Workload Management System was performed; a 4 times increase in throughput with respect to LCG Resource Broker is observed. CMS has designed and launched a new-generation traffic load generator called "LoadTest" to commission and to keep exercised all data transfer routes in the CMS PhE-DEx topology. Since mid-February, a transfer volume of about 12 P...

  17. LIMES: A computer program for analyses of light and intermediate-mass fragment emission in heavy ion reactions by an extended sum-rule model

    International Nuclear Information System (INIS)

    Brancus, I.M.; Wentz, J.; Hohn, H.U.

    1989-10-01

    The computer program LIMES is based on an improved version of the extended sum-rule model for light and intermediate-mass fragment emission in heavy ion reactions. It includes a code for dynamical calculations of the critical angular momentum for fusion following the suggestions. The report briefly describes the use of this program, the necessary input for the calculations of the element distribution and partial cross sections and gives a Fortran listing. Using the fitting routine FITEX the program provides an option for fast parameter adjustments. The use is demonstrated by an application to a specific example. (orig.) [de

  18. Review of Cardiovascular Imaging in the Journal of Nuclear Cardiology in 2016. Part 1 of 2: Positron Emission Tomography, Computed Tomography and Magnetic Resonance.

    Science.gov (United States)

    AlJaroudi, Wael; Hage, Fadi G

    2017-04-01

    Several original articles and editorials have been published in the Journal of Nuclear Cardiology last year. It has become a tradition at the beginning of each year to summarize some of these key articles (AlJaroudi and Hage in J Nucl Cardiol 22:507-512, 2015, 23:122-130, 2016; Hage and AlJaroudi in J Nucl Cardiol 22:714-719, 2015; 23:493-498, 2016). In this part one, we will discuss some of the progress made in patients with infiltrative disease, cardiomyopathies (non-ischemic, ischemic, and diabetic), hybrid and molecular imaging, using advancement in positron emission tomography, computed tomography, and magnetic resonance imaging.

  19. Post meningitis subdural hygroma: Anatomical and functional evaluation with (99m)Tc-ehylene cysteine dimer single photon emission tomography/computed tomography.

    Science.gov (United States)

    Sharma, Punit; Mishra, Ajiv; Arora, Geetanjali; Tripathi, Madhavi; Bal, Chandrasekhar; Kumar, Rakesh

    2013-01-01

    Subdural hygroma is the collection of cerebrospinal fluid in the subdural space. Most often these resolve spontaneously. However, in cases with neurological complications surgical drainage may be needed. We here, present the case of an 8-year-old boy with post meningitis subdural hygroma. (99m)Tc-ehylene cysteine dimer ((99m)Tc-ECD) hybrid single photon emission tomography/computed tomography (SPECT/CT) carried out in this patient, demonstrated the subdural hygroma as well as the associated cerebral hypoperfusion. If (99m)Tc-ECD SPECT/CT is integrated into management of these patients, it can help in decision making with respect to conservative versus surgical management.

  20. [Adenosine triphosphate stress 99mTc-MIBI single-photon emission computed tomography in the diagnosis of ischemic heart disease].

    Science.gov (United States)

    Karpova, I E; Samoĭlenko, L E; Soboleva, G N; Sergienko, V B; Karpov, Iu A

    2013-01-01

    This review is devoted to possibilities of single-photon emission computed tomography (SPECT) combined with pharmacological test with adenosine triphosphate (ATP) to detect myocardial ischemia in patients with ischemic heart disease (IHD). It contains consideration of contemporary problems and limitations inherent in use of pharmacological stress tests in radionuclide diagnostics; discussion of mechanisms of vasodilating effects of ATP in the context of modern concepts of purine receptors; detailed description of technique of pharmacological testing with ATP, as well as contraindications and possible side effects. Experience of foreign studies with the use of ATP stress testing for verification of presence of ischemia in patients with IHD is also presented.

  1. An interesting case of polyostotic fibrous dysplasia: The “pirate sign” evaluated with Tc-99m methylene diphosphonate single-photon emission computed tomography/computerized tomography

    International Nuclear Information System (INIS)

    Harisankar, Chidambaram Natarajan Balasubramanian; Bhattacharya, Anish; Bhadada, Sanjay Kumar; Kamaleshwaran, Koramadai Karuppusamy; Mittal, Bhagwant Rai

    2011-01-01

    Polyostotic fibrous dysplasia is a rare progressive benign disorder of the bone. Bone scintigraphy is extremely useful in the initial evaluation for identifying the extent of disease. We report a case presenting with pathological fracture of the shaft of the right femur. After treatment of the fracture, bone scintigraphy revealed involvement of multiple bones including the skull and facial bones. The utility of single-photon emission computed tomography/computerized tomography in the evaluation of the extent of skull base involvement is highlighted

  2. In vivo measurement of haloperidol affinity to dopamine D2/D3 receptors by [123I]IBZM and single photon emission computed tomography

    DEFF Research Database (Denmark)

    Videbaek, C; Toska, K; Friberg, L

    2001-01-01

    This study examines the feasibility of a steady-state bolus-integration method with the dopamine D2/D3 receptor single photon emission computer tomography (SPECT) tracer, [123I]IBZM, for determination of in vivo affinity of haloperidol. The nonspecific binding of [123I]IBZM was examined in the rat...... brain by infusion of haloperidol to plasma levels approximately 100 times the Kd level in man. In humans, Kd for haloperidol binding was measured in four healthy volunteers that were examined twice: once with partial dopamine D2/D3 receptor blockade obtained by a scheduled infusion of unlabeled...

  3. Association of Novelty Seeking Scores and Striatal Dopamine D2/D3 Receptor Availability of Healthy Volunteers: Single Photon Emission Computed Tomography With 123I-iodobenzamide

    Directory of Open Access Journals (Sweden)

    Hsiang Yu Huang

    2010-10-01

    Full Text Available It has been speculated that novelty seeking (NS behavior is related to the dopaminergic system. Fifty-two subjects completed the Tridimensional Personality Questionnaire and underwent single photon emission computed tomography with 123I-iodobenzamide. A marginally positive correlation was noted between NS and striatal dopamine D2/D3 receptor availability (r = 0.25, p =0.07. A positive association was noted between the NS scores and left striatal D2/D3 receptor availability (r= 0.29, p =0.04. The results suggest that a relationship might exist between NS score and dopaminergic activity.

  4. A rare case of extensive skeletal muscle metastases in adenocarcinoma cervix identified by 18F-fluorodeoxyglucose positron emission tomography/computed tomography scan

    International Nuclear Information System (INIS)

    Vishnoi, Madan Gopal; Jain, Anurag; John, Arun Ravi; Paliwal, Dharmesh

    2016-01-01

    Adenocarcinoma cervix is an uncommon histological subtype of carcinoma cervix; further incidence of skeletal muscle metastases is even rarer. We report the identification of extensive fluorodeoxyglucose (FDG) avid metastatic skeletal muscle deposits in a known case of adenocarcinoma cervix. The largest lesion representative of muscle deposit in the right deltoid was histopathologically confirmed to be metastatic poorly differentiated carcinoma. This report also serves to highlight the importance of 18 F-FDG positron emission tomography/computed tomography (CT) as compared to conventional imaging modalities such as CT and ultrasonography and comments better over the description of invasiveness as well as the extent of disease in carcinoma cervix

  5. An incidentally found inflamed uterine myoma Causing low abdominal pain, using TC-99m-tektrotyd single photon emission computed tomography-CT hybrid imaging

    Energy Technology Data Exchange (ETDEWEB)

    Zandieh, Shahin; Schuetz, Matthias; Bernt, Reinhard; Zwerina, Jochen; Haller, Joerg [Hanusch-Hospital, Teaching Hospital of Medical University of Vienna, Vienna (Australia)

    2013-10-15

    We report the case of a 50-year-old woman presented with a history of right hemicolectomy due to an ileocecal neuroendocrine tumor and left breast metastasis. Owing to a slightly elevated chromogranin A-level and lower abdominal pain, single photon emission computed tomography-computer tomography (SPECT-CT) was performed. There were no signs of recurrence on the SPECT-CT scan, but the patient was incidentally found to have an inflamed intramural myoma. We believe that the slightly elevated chromogranin A-level was caused by the hypertension that the patient presented. In the clinical context, this is a report of an inflamed uterine myoma seen as a false positive result detected by TC-99m-Tc-EDDA/HYNIC-Tyr3-Octreotide (Tektrotyd) SPECT-CT hybrid imaging.

  6. An incidentally found inflamed uterine myoma causing low abdominal pain, using Tc-99m-tektrotyd single photon emission computed tomography-CT hybrid imaging.

    Science.gov (United States)

    Zandieh, Shahin; Schütz, Matthias; Bernt, Reinhard; Zwerina, Jochen; Haller, Joerg

    2013-01-01

    We report the case of a 50-year-old woman presented with a history of right hemicolectomy due to an ileocecal neuroendocrine tumor and left breast metastasis. Owing to a slightly elevated chromogranin A-level and lower abdominal pain, single photon emission computed tomography-computer tomography (SPECT-CT) was performed. There were no signs of recurrence on the SPECT-CT scan, but the patient was incidentally found to have an inflamed intramural myoma. We believe that the slightly elevated chromogranin A-level was caused by the hypertension that the patient presented. In the clinical context, this is a report of an inflamed uterine myoma seen as a false positive result detected by TC-99m-Tc-EDDA/HYNIC-Tyr3-Octreotide (Tektrotyd) SPECT-CT hybrid imaging.

  7. Computational fluid dynamics simulation of the combustion process, emission formation and the flow field in an in-direct injection diesel engine

    Directory of Open Access Journals (Sweden)

    Barzegar Ramin

    2013-01-01

    Full Text Available In the present paper, the combustion process and emission formation in the Lister 8.1 I.D.I Diesel engine have been investigated using a Computational Fluid Dynamics (CFD code. The utilized model includes detailed spray atomization, mixture formation and distribution model which enable modeling the combustion process in spray/wall and spray/swirl interactions along with flow configurations. The analysis considers both part load and full load states. The global properties are presented separately resolved for the swirl chamber (pre-chamber and the main chamber. The results of model verify the fact that the equal amount of the fuel is burned in the main and pre-chamber at full load state while at part load the majority of the fuel is burned in the main chamber. Also, it is shown that the adherence of fuel spray on the pre-chamber walls is due to formation of a stagnation zone which prevents quick spray evaporation and plays an important role in the increase of soot mass fractions at this zone at full load conditions. The simulation results, such as the mean in-cylinder pressure, heat release rate and exhaust emissions are compared with the experimental data and show good agreement. This work also demonstrates the usefulness of multidimensional modeling for complex chamber geometries, such as in I.D.I Diesel engines, to gain more insight into the flow field, combustion process and emission formation.

  8. Prospective, blinded trial of whole-body magnetic resonance imaging versus computed tomography positron emission tomography in staging primary and recurrent cancer of the head and neck.

    LENUS (Irish Health Repository)

    O'Neill, J P

    2012-02-01

    OBJECTIVES: To compare the use of computed tomography - positron emission tomography and whole-body magnetic resonance imaging for the staging of head and neck cancer. PATIENTS AND METHODS: From January to July 2009, 15 consecutive head and neck cancer patients (11 men and four women; mean age 59 years; age range 19 to 81 years) underwent computed tomography - positron emission tomography and whole-body magnetic resonance imaging for pre-therapeutic evaluation. All scans were staged, as per the American Joint Committee on Cancer tumour-node-metastasis classification, by two blinded consultant radiologists, in two sittings. Diagnoses were confirmed by histopathological examination of endoscopic biopsies, and in some cases whole surgical specimens. RESULTS: Tumour staging showed a 74 per cent concordance, node staging an 80 per cent concordance and metastasis staging a 100 per cent concordance, comparing the two imaging modalities. CONCLUSION: This study found radiological staging discordance between the two imaging modalities. Whole-body magnetic resonance imaging is an emerging staging modality with superior visualisation of metastatic disease, which does not require exposure to ionising radiation.

  9. Quantification of myocardial area at risk in the absence of collateral flow: the validation of angiographic scores by myocardial perfusion single-photon emission computed tomography.

    Science.gov (United States)

    Rodríguez-Palomares, José F; Alonso, Albert; Martí, Gerard; Aguadé-Bruix, Santiago; González-Alujas, M T; Romero-Farina, Guillermo; Candell-Riera, Jaume; García del Blanco, Bruno; Evangelista, Artur; García-Dorado, David

    2013-02-01

    Our study aimed to compare the area at risk (AAR) determined by single-photon emission computed tomography (SPECT) with the Bypass Angioplasty Revascularization Investigation (BARI) and modified Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) angiographic scores in the setting of patients undergoing coronary angioplasty for either unstable angina or an STEMI. Radionuclide myocardial perfusion imaging prior to reperfusion has classically been the most widely practised technique for assessing the AAR and has been successfully used to compare the efficacy of various reperfusion strategies in patients with an ST-segment elevation myocardial infarction (STEMI). The BARI and modified APPROACH scores are angiographic methods widely used to provide a rapid estimation of the AAR; however, they have not been directly validated with myocardial perfusion single-photon emission computed tomography (SPECT). Fifty-five patients with no previous myocardial infarction who underwent coronary angioplasty for single-vessel disease (unstable angina: n = 25 or an STEMI: n = 30) with no evidence of collaterals (Rentrop Collateral Score collateral flow, BARI and APPROACH scores constitute valid methods for AAR estimation in current clinical practice, with more accurate results when used for the LAD territory; both are useful not only in STEMI patients but also in patients with unstable angina.

  10. Prediction of Central Nervous System Relapse of Diffuse Large B-Cell Lymphoma Using Pretherapeutic [18F]2-Fluoro-2-Deoxyglucose (FDG) Positron Emission Tomography/Computed Tomography.

    Science.gov (United States)

    Song, Yoo Sung; Lee, Won Woo; Lee, Jong Seok; Kim, Sang Eun

    2015-11-01

    Central nervous system (CNS) relapse of diffuse large B-cell lymphoma (DLBCL) is a rare complication, but has a poor prognosis with unknown pathophysiology. Recent trials of CNS prophylaxis have shown to be ineffective, despite patient's selection using several known clinical risk factors. In this study, the authors evaluated the value of pretreatment [F]2-Fluoro-2-deoxyglucose positron emission tomography in predicting CNS relapse in DLBCL patients.The authors analyzed 180 pathologically confirmed DLBCL patients, retrospectively. Patients underwent [F]2-Fluoro-2-deoxyglucose positron emission tomography/computed tomography before first line rituximab to cyclophosphamide, doxorubicin, vincristine, and prednisone therapy. Clinical characteristics were evaluated and total lesion glycolysis (TLG) with a threshold margin of 50% was calculated.Among age, sex, Ann Arbor stage, International Prognostic Index, revised International Prognostic Index, high serum lactate dehydrogenase level, presence of B symptoms, bulky disease (≥10 cm), extranodal lesion involvement, bone marrow involvement, high metabolic tumor volume ( >450 mL), and high TLG50 (>2000), the high TLG50 was the only significant prognostic factor for predicting CNS relapse in a multivariate analysis (P = 0.04). Kaplan-Meir survival analysis between high TLG50 (>2000) and low TLG50 (≤2000) groups revealed significantly different mean progression free survival (PFS) of 1317.2 ± 134.3 days and 1968.6 ± 18.3 days, respectively (P positron emission tomography/computed tomography is the most significant predictor of CNS relapse in un-treated DLBCL patients.

  11. Positron emission tomography response criteria in solid tumours criteria for quantitative analysis of [18F]-fluorodeoxyglucose positron emission tomography with integrated computed tomography for treatment response assessment in metastasised solid tumours: All that glitters is not gold.

    Science.gov (United States)

    Willemsen, Annelieke E C A B; Vlenterie, Myrella; van Herpen, Carla M L; van Erp, Nielka P; van der Graaf, Winette T A; de Geus-Oei, Lioe-Fee; Oyen, Wim J G

    2016-03-01

    For solid tumours, quantitative analysis of [(18)F]-fluorodeoxyglucose positron emission tomography with integrated computed tomography potentially can have significant value in early response assessment and thereby discrimination between responders and non-responders at an early stage of treatment. Standardised strategies for this analysis have been proposed, and the positron emission tomography response criteria in solid tumours (PERCIST) criteria can be regarded as the current standard to perform quantitative analysis in a research setting, yet is not implemented in daily practice. However, several exceptions and limitations limit the feasibility of PERCIST criteria. In this article, we point out dilemmas that arise when applying proposed criteria like PERCIST on an expansive set of patients with metastasised solid tumours. Clinicians and scientists should be aware of these limitations to prevent that methodological issues impede successful introduction of research data into clinical practice. Therefore, to deliver on the high potential of quantitative imaging, consensus should be reached on a standardised, feasible and clinically useful analysis methodology. This methodology should be applicable in the majority of patients, tumour types and treatments. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. TH-C-BRD-01: Analytical Computation of Prompt Gamma Ray Emission and Detection for Proton Range Verification

    International Nuclear Information System (INIS)

    Sterpin, E; Vynckier, S; Janssens, G; Smeets, J; Prieels, D

    2014-01-01

    Purpose: A prompt gamma (PG) slit camera prototype demonstrated that on-line range monitoring within 1–2 mm could be performed by comparing expected and measured PG detection profiles. Monte Carlo (MC) can simulate the expected PG profile but this would result in prohibitive computation time for a complete pencil beam treatment plan. We implemented a much faster method that is based on analytical processing of pre-computed MC data. Methods: The formation of the PG detection signal can be separated into: 1) production of PGs and 2) detection by the camera detectors after PG transport in geometry. For proton energies from 40 to 230 MeV, PG productions in depth were pre-computed by MC (PENH) for 12C, 14N, 16O, 31P and 40Ca. The PG production was then modeled analytically by adding the PG production for each element according to local proton energy and tissue composition.PG transport in the patient/camera geometries and the detector response were modeled by convolving the PG production profile with a transfer function. The latter is interpolated from a database of transfer functions fitted to pre-computed MC data (PENELOPE). The database was generated for a photon source in a cylindrical phantom with various radiuses and a camera placed at various positions.As a benchmark, the analytical model was compared to PENH for a water phantom, a phantom with different slabs (adipose, muscle, lung) and a thoracic CT. Results: Good agreement (within 5%) was observed between the analytical model and PENH for the PG production. Similar accuracy for detecting range shifts was also observed. Speed of around 250 ms per profile was achieved (single CPU) using a non-optimized MatLab implementation. Conclusion: We devised a fast analytical model for generating PG detection profiles. In the test cases considered in this study, similar accuracy than MC was achieved for detecting range shifts. This research is supported by IBA

  13. Positron Emission Tomography/Magnetic Resonance Imaging for Local Tumor Staging in Patients With Primary Breast Cancer: A Comparison With Positron Emission Tomography/Computed Tomography and Magnetic Resonance Imaging.

    Science.gov (United States)

    Grueneisen, Johannes; Nagarajah, James; Buchbender, Christian; Hoffmann, Oliver; Schaarschmidt, Benedikt Michael; Poeppel, Thorsten; Forsting, Michael; Quick, Harald H; Umutlu, Lale; Kinner, Sonja

    2015-08-01

    This study aimed to assess the diagnostic performance of integrated positron emission tomography (PET)/magnetic resonance imaging (MRI) of the breast for lesion detection and local tumor staging of patients with primary breast cancer in comparison to PET/computed tomography (CT) and MRI. The study was approved by the local institutional review board. Forty-nine patients with biopsy-proven invasive breast cancer were prospectively enrolled in our study. All patients underwent a PET/CT, and subsequently, a contrast-enhanced PET/MRI of the breast after written informed consent was obtained before each examination. Two radiologists independently evaluated the corresponding data sets (PET/CT, PET/MRI, and MRI) and were instructed to identify primary tumors lesions as well as multifocal/multicentric and bilateral disease. Furthermore, the occurrence of lymph node metastases was assessed, and the T-stage for each patient was determined. Histopathological verification of the local tumor extent and the axillary lymph node status was available for 30 of 49 and 48 of 49 patients, respectively. For the remaining patients, a consensus characterization was performed for the determination of the T-stage and nodal status, taking into account the results of clinical staging, PET/CT, and PET/MRI examinations. Statistical analysis was performed to test for differences in diagnostic performance between the different imaging procedures. P values less than 0.05 were considered to be statistically significant. Positron emission tomography/MRI and MRI correctly identified 47 (96%) of the 49 patients with primary breast cancer, whereas PET/CT enabled detection of 46 (94%) of 49 breast cancer patients and missed a synchronous carcinoma in the contralateral breast in 1 patient. In a lesion-by-lesion analysis, no significant differences could be obtained between the 3 imaging procedures for the identification of primary breast cancer lesions (P > 0.05). Positron emission tomography/MRI and

  14. Computing the Absorption and Emission Spectra of 5-Methylcytidine in Different Solvents: A Test-Case for Different Solvation Models.

    Science.gov (United States)

    Martínez-Fernández, L; Pepino, A J; Segarra-Martí, J; Banyasz, A; Garavelli, M; Improta, R

    2016-09-13

    The optical spectra of 5-methylcytidine in three different solvents (tetrahydrofuran, acetonitrile, and water) is measured, showing that both the absorption and the emission maximum in water are significantly blue-shifted (0.08 eV). The absorption spectra are simulated based on CAM-B3LYP/TD-DFT calculations but including solvent effects with three different approaches: (i) a hybrid implicit/explicit full quantum mechanical approach, (ii) a mixed QM/MM static approach, and (iii) a QM/MM method exploiting the structures issuing from molecular dynamics classical simulations. Ab-initio Molecular dynamics simulations based on CAM-B3LYP functionals have also been performed. The adopted approaches all reproduce the main features of the experimental spectra, giving insights on the chemical-physical effects responsible for the solvent shifts in the spectra of 5-methylcytidine and providing the basis for discussing advantages and limitations of the adopted solvation models.

  15. Comparison of planar scanning and single photon emission computed tomography in the diagnosis of avascular necrosis of the femoral head

    International Nuclear Information System (INIS)

    Feiglin, D.H.I.; Levine, M.; Stulberg, B.; Pflanze, W.; O'Donnell, J.K.; Belhobek, G.H.; Go, R.T.; MacIntyre, W.J.

    1986-01-01

    Thirty-nine patients were investigated for avascular necrosis of the femoral head. All hips were studied by plain x-ray and MR imaging, 70 hips studied by radionuclide bone scanning, and 38 were studied by single photon emission CT (SPECT). Core biopsies of the femoral heads from 32 hips were examined. No one reference standard for noninvasive diagnosis of this disease is available. The sensitivity and specificity of the radionuclide studies with respect to SPECT were 77% and 100%; of SPECT with respect to pathologic confirmation, 100% and 57%; of MR imaging with respect to pathologic studies, 100% and 66%. Pathologic sampling is subject to error and may give false negative results with spuriously low specificities for imaging modalities. SPECT is recommended as the radionuclide imaging procedure of choice for detecting avascular necrosis of the femoral head

  16. Handheld single photon emission computed tomography (handheld SPECT) navigated video-assisted thoracoscopic surgery of computer tomography-guided radioactively marked pulmonary lesions.

    Science.gov (United States)

    Müller, Joachim; Putora, Paul Martin; Schneider, Tino; Zeisel, Christoph; Brutsche, Martin; Baty, Florent; Markus, Alexander; Kick, Jochen

    2016-09-01

    Radioactive marking can be a valuable extension to minimally invasive surgery. The technique has been clinically applied in procedures involving sentinel lymph nodes, parathyroidectomy as well as interventions in thoracic surgery. Improvements in equipment and techniques allow one to improve the limits. Pulmonary nodules are frequently surgically removed for diagnostic or therapeutic reasons; here video-assisted thoracoscopic surgery (VATS) is the preferred technique. VATS might be impossible with nodules that are small or located deep in the lung. In this study, we examined the clinical application and safety of employing the newly developed handheld single photon emission tomography (handheld SPECT) device in combination with CT-guided radioactive marking of pulmonary nodules. In this pilot study, 10 subjects requiring surgical resection of a pulmonary nodule were included. The technique involved CT-guided marking of the target nodule with a 20-G needle, with subsequent injection of 25-30 MBq (effective: 7-14 MBq) Tc-99m MAA (Macro Albumin Aggregate). Quality control was made with conventional SPECT-CT to confirm the correct localization and exclude possible complications related to the puncture procedure. VATS was subsequently carried out using the handheld SPECT to localize the radioactivity intraoperatively and therefore the target nodule. A 3D virtual image was superimposed on the intraoperative visual image for surgical guidance. In 9 of the 10 subjects, the radioactive application was successfully placed directly in or in the immediate vicinity of the target nodule. The average size of the involved nodules was 9 mm (range 4-15). All successfully marked nodules were subsequently completely excised (R0) using VATS. The procedure was well tolerated. An asymptomatic clinically insignificant pneumothorax occurred in 5 subjects. Two subjects were found to have non-significant discrete haemorrhage in the infiltration canal of the needle. In a single subject, the

  17. Isolated thymic Langerhans cell histiocytosis discovered on F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT)

    Energy Technology Data Exchange (ETDEWEB)

    Turpin, Sophie [CHU Sainte-Justine, Nuclear Medicine, Montreal (Canada); Carret, Anne-Sophie [CHU Sainte-Justine, Hemato-Oncology, Montreal (Canada); Dubois, Josee [CHU Sainte-Justine, Radiology, Montreal (Canada); Buteau, Chantal [CHU Sainte-Justine, Infectious Diseases, Montreal (Canada); Patey, Natalie [CHU Sainte-Justine, Pathology, Montreal (Canada)

    2015-11-15

    The thymic infiltration in young patients with multisystemic Langerhans cell histiocytosis and its radiologic features are well known. However, isolated thymic disease has seldom been reported in the literature. We report the case of a 10-month-old child admitted for fever of unknown origin. Whole-body F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) was performed to identify a focus of infection. It demonstrated an unusual aspect of the thymus, which led to further investigation and revealed isolated infiltration of the thymus by Langerhans cell histiocytosis. The patient was treated accordingly and is now disease free. As evaluation of Langerhans cell histiocytosis patients with F-18 FDG PET/CT is becoming more frequent, it is important to be aware of the scintigraphical characteristics of thymic Langerhans cell histiocytosis. (orig.)

  18. Isolated thymic Langerhans cell histiocytosis discovered on F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT).

    Science.gov (United States)

    Turpin, Sophie; Carret, Anne-Sophie; Dubois, Josée; Buteau, Chantal; Patey, Natalie

    2015-11-01

    The thymic infiltration in young patients with multisystemic Langerhans cell histiocytosis and its radiologic features are well known. However, isolated thymic disease has seldom been reported in the literature. We report the case of a 10-month-old child admitted for fever of unknown origin. Whole-body F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) was performed to identify a focus of infection. It demonstrated an unusual aspect of the thymus, which led to further investigation and revealed isolated infiltration of the thymus by Langerhans cell histiocytosis. The patient was treated accordingly and is now disease free. As evaluation of Langerhans cell histiocytosis patients with F-18 FDG PET/CT is becoming more frequent, it is important to be aware of the scintigraphical characteristics of thymic Langerhans cell histiocytosis.

  19. {sup 68}Gallium-arginine-glycine-aspartic acid and {sup 18}F-fluorodeoxyglucose position emission tomography/computed tomography in chondroblastic osteosarcoma of the skull

    Energy Technology Data Exchange (ETDEWEB)

    Orunmuyi, Akintunde; Modiselle, Moshe; Lengana, Thabo; Ebenhan, Thomas; Vorster, Mariza; Sathekge, Mike [Dept. of Nuclear MedicineUniversity of Pretoria and Steve Biko Academic Hospital, Pretoria (South Africa)

    2017-09-15

    We report the case of a 32 year-old male with Chondroblastic Osteosarcoma of the skull, which was imaged with both {sup 18}[F]fluorodeoxyglucose ({sup 18}F-FDG) positron emission tomography/computed tomography (PET/CT) and {sup 68}Gallium-arginine-glycine-aspartic acid ({sup 68}Ga-RGD) PET/CT. The {sup 18}F-FDG PET/CT did not demonstrate the tumour, whereas the {sup 68}Ga-RGD PET/CT clearly depicted a left-sided frontal tumour. {sup 68}Ga-RGD PET/CT may be a clinically useful imaging modality for early detection of recurrent osteosarcoma, considering the limitations of {sup 18}F-FDG PET in a setting of low glycolytic activity.

  20. Infective endocarditis detected by 18F-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography in a patient with occult infection

    Directory of Open Access Journals (Sweden)

    Chia-Lu Yeh

    2011-11-01

    Full Text Available Integrated 18F-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (FDG PET/CT has been clinically used to detect infectious lesions. We present a case with pyrexia and bacteremia of unknown origin. Whole body FDG PET/CT was arranged to look for an occult source of infection and it revealed a focal lesion with increased FDG uptake in the mitral valve area. Under suspicion of infective endocarditis, transthoracic echocardiography was repeated and then the presence of linear vegetation over the calcified mitral annulus was confirmed. Ultimately, definite infective endocarditis was diagnosed according to the Duke criteria. The patient recovered after the antibiotic therapy. In our case, FDG PET/CT can help to localize the exact site of occult infection, thereby guiding additional testing and facilitating timely definitive diagnosis and therapy.

  1. The Marinesco-Sjoegren syndrome examined by computed tomography, magnetic resonance, and 18F-2-fluoro-2-deoxy-D-glucose and positron emission tomography

    International Nuclear Information System (INIS)

    Bromberg, M.B.; Junck, L.; Gebarski, S.S.; McLean, M.J.; Gilman, S.

    1990-01-01

    The Marinesco-Sjoegren syndrome is an autosomal recessive degenerative disorder characterized by congenital cataracts, cerebellar ataxia, spasticity, mental deficiency, and skeletal abnormalities. We studied two adult siblings with Marinesco-Sjoegren syndrome using anatomic and metabolic brain imaging techniques to characterize the pattern and nature of abnormalities in the brain. Computed tomographic and magnetic resonance imaging showed diffuse brain atrophy of mild to moderate degree, involving primarily the white matter of the cerebrum, cerebellum, brain stem, and cervical spinal cord. The pattern of atrophy resembled that seen in diffuse leukoencephalopathies. Measurements of local cerebral glucose metabolic rates with positron emission tomography revealed no statistically significant differences from normal control subjects in most regions, but metabolic rate was decreased in the thalamus in one patient. The findings support a diffuse white matter disorder in Marinesco-Sjoegren syndrome.Aut

  2. Post meningitis subdural hygroma: anatomical and functional evaluation with 99mTc-ethylene cysteine dimer single photon emission tomography/computed tomography

    International Nuclear Information System (INIS)

    Sharma, Punit; Mishra, Ajiv; Arora, Geetanjali; Tripathi, Madhavi; Bal, Chandrasekhar; Kumar, Rakesh

    2013-01-01

    Subdural hygroma is the collection of cerebrospinal fluid in the subdural space. Most often these resolve spontaneously. However, in cases with neurological complications surgical drainage may be needed. We here, present the case of an 8-year-old boy with post meningitis subdural hygroma. 99m Tc-ethylene cysteine dimer ( 99m Tc-ECD) hybrid single photon emission tomography/computed tomography (SPECT/CT) carried out in this patient, demonstrated the subdural hygroma as well as the associated cerebral hypoperfusion. If 99m Tc-ECD SPECT/CT is integrated into management of these patients, it can help in decision making with respect to conservative versus surgical management. (author)

  3. 18F-fluoro-deoxy-glucose-positron emission tomography/computed tomography in diagnosis of head and neck squamous cell carcinoma

    DEFF Research Database (Denmark)

    Rohde, Max; Dyrvig, Anne-Kirstine; Johansen, Jørgen

    2014-01-01

    18F-fluoro-deoxy-glucose-positron emission tomography/computed tomography-scan (PET/CT) is used increasingly for detection of cancer. Precise diagnostic assessment of tumour extension in head and neck squamous cell carcinoma (HNSCC) is of critical importance for ensuring that patients receive...... proper treatment. Preliminary studies have shown divergent results of PET/CT in diagnosis and staging of HNSCC. The aims of this study were (1) to systematically review and meta-analyse published data about the diagnostic accuracy of PET/CT for diagnosing patients with HNSCC and (2) to compare...... the diagnostic accuracy of PET/CT with that of standard conventional imaging (SCI). METHODS: A systematic literature search in the PubMed, Embase and Cochrane databases on publications of PET/CT diagnostics of HNSCC from January 2005 to July 2013 was carried out. All retrieved studies were reviewed...

  4. Kikuchi Disease with Generalized Lymph Node, Spleen and Subcutaneous Involvement Detected by Fluorine-18-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography

    Directory of Open Access Journals (Sweden)

    Alshaima Alshammari

    2016-06-01

    Full Text Available Kikuchi-Fujimoto disease, known as Kikuchi disease, is a rare benign and self-limiting disorder that typically affects the regional cervical lymph nodes. Generalized lymphadenopathy and extranodal involvement are rare. We report a rare case of a 19-yearold female with a history of persistent fever, nausea, and debilitating malaise. Fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT revealed multiple hypermetabolic generalized lymph nodes in the cervical, mediastinum, axillary, abdomen and pelvic regions with diffuse spleen, diffuse thyroid gland, and focal parotid involvement, bilaterally. In addition, subcutaneous lesions were noted in the left upper paraspinal and occipital regions. An excisional lymph node biopsy guided by 18F-FDG PET/CT revealed the patient’s diagnosis as Kikuchi syndrome.

  5. In vivo measurement of haloperidol affinity to dopamine D2/D3 receptors by [123I]IBZM and single photon emission computed tomography

    DEFF Research Database (Denmark)

    Videbaek, C; Toska, K; Friberg, L

    2001-01-01

    This study examines the feasibility of a steady-state bolus-integration method with the dopamine D2/D3 receptor single photon emission computer tomography (SPECT) tracer, [123I]IBZM, for determination of in vivo affinity of haloperidol. The nonspecific binding of [123I]IBZM was examined in the rat...... brain by infusion of haloperidol to plasma levels approximately 100 times the Kd level in man. In humans, Kd for haloperidol binding was measured in four healthy volunteers that were examined twice: once with partial dopamine D2/D3 receptor blockade obtained by a scheduled infusion of unlabeled...... haloperidol (0.7 mg total dosage), and once in an unblocked state. Blood sampling and SPECT were performed intermittently during 6 hours after intravenous [123I]IBZM bolus injection. Plasma [123I]IBZM was determined by octane extraction. Plasma haloperidol was determined by a radioimmunoassay, and plasma...

  6. Acute effect of electroconvulsive therapy on brain perfusion assessed by Tc99m-hexamethylpropyleneamineoxim and single photon emission computed tomography

    International Nuclear Information System (INIS)

    Bajc, M.; Basic, M.; Topuzovic, N.; Babic, D.; Ivancevic, D.; Medved, V.

    1989-01-01

    Regional cerebral blood flow (rCBF) was measured in relative terms with Tc99m-hexamethylpropyleneamineoxim and single photon emission computed tomography in 11 patients undergoing electroconvulsive therapy (ECT). The patients suffered from major depressive disorder (n=8) or schizoaffective disorders (n=3). rCBF was measured under general anesthesia 3 days prior to the ECT treatment and coinciding with the ECT stimualtion. ECT caused a redistribution of the tracers uptake. The uptake became more pronounced in frontal parts of the brain and in the basal ganglia than in posterior parts of the cortex, and the thalamus. This selective effect of ECT on rCBF may be related to catecholaminergic projections to anterior parts of the brain. (author)

  7. Single photon emission computed tomography (SPECT) findings using N-isopropyl-p-[123I]iodoamphetamine (123I-IMP) in schizophrenia and atypical psychosis

    International Nuclear Information System (INIS)

    Suga, Hidemichi; Hayashi, Takuji; Mitsugi, Ohara

    1994-01-01

    As a basis for possible classification of schinzophrenic psychoses into schizophrenia and atypical psychosis, we studied the brain functional differences among 16 schizophrenic patients, 16 atypical psychosis patients and 16 healthy volunteers by single photon emission computed tomography (SPECT) using N-isopropyl-p-[ 123 I] iodoamphetamine. As a result, schizophrenics showed hypofrontality. On the other hand, atypical psychotics had no such hypofrontality but showed a reduced uptake rate in the right thalamic region. No influence of sex, duration of illness and medication was confirmed by the findings. The results suggest that schizophrenics might have some lesions in the frontal regions, whereas atypical psychotics might have no such lesions, but dysfunction in the right thalamic region. Consequently, the SPECT findings as least indicate possibly different etiologies for schizophrenia and atypical psychosis. (author)

  8. Single photon emission computed tomography (SPECT) findings using N-isopropyl-p-[{sup 123}I]iodoamphetamine ({sup 123}I-IMP) in schizophrenia and atypical psychosis

    Energy Technology Data Exchange (ETDEWEB)

    Suga, Hidemichi; Hayashi, Takuji; Mitsugi, Ohara [Aichi Medical Univ., Nagakute (Japan)

    1994-12-01

    As a basis for possible classification of schinzophrenic psychoses into schizophrenia and atypical psychosis, we studied the brain functional differences among 16 schizophrenic patients, 16 atypical psychosis patients and 16 healthy volunteers by single photon emission computed tomography (SPECT) using N-isopropyl-p-[{sup 123}I] iodoamphetamine. As a result, schizophrenics showed hypofrontality. On the other hand, atypical psychotics had no such hypofrontality but showed a reduced uptake rate in the right thalamic region. No influence of sex, duration of illness and medication was confirmed by the findings. The results suggest that schizophrenics might have some lesions in the frontal regions, whereas atypical psychotics might have no such lesions, but dysfunction in the right thalamic region. Consequently, the SPECT findings as least indicate possibly different etiologies for schizophrenia and atypical psychosis. (author).

  9. Fluorodeoxyglucose positron emission tomography-computed tomography scan in von Hippel-Lindau syndrome: a case report and review of literature

    International Nuclear Information System (INIS)

    Solav, Shrikant; Bhandari, Ritu

    2012-01-01

    Von Hippel-Lindau (VHL) syndrome is a hereditary autosomal dominant disorder caused by defective tumor suppression gene at 3p25-p26. The gene for VHL disease is found on chromosome 3, and is inherited in a dominant fashion. The VHL gene is a tumor suppressor gene. This means that its role in a normal cell is to stop the uncontrolled growth and proliferation. It is characterized by abnormal growth of blood vessels. It strikes the eyes, central nervous system, kidneys, endocrine glands, etc. It predisposes the patient to retinal angiomas, central nervous system hemangioblastoma, renal cell carcinoma (RCC), pheochromocytomas, islet cell tumor of the pancreas, endolymphatic sac tumors, renal, pancreatic, epididymal cysts. We present a case of familial VHL syndrome whose Fluorine 18-fluorodeoxyglucose positron emission tomography-computed tomography scan was truly positive for adrenal pheochromocytoma but was falsely negative for RCC. Review of literature related to this entity is made. (author)

  10. Single photon emission computed tomography of technetium-99m tetrofosmin myocardial perfusion imaging in patients with systemic lupus erythematosus-A preliminary report

    International Nuclear Information System (INIS)

    Lin, Jen-Jhy; Hsu, Hsiu-Bao; Sun, Shung-Shung; Kao, Chia-Hung; Ho, Shung-Tai

    2003-01-01

    The purpose of this study was to evaluate the utility of single-photon emission computed tomography (SPECT) of technetium-99m tetrofosmin (Tc-99m TF) myocardial perfusion imaging to detect myocardial involvement in patients with systemic lupus erythematosus (SLE). Three groups of subjects-group 1: 25 SLE female patients with non-specific cardiac symptoms and signs, group 2: 25 female SLE patients without any cardiac symptoms and signs, and group 3: 25 female healthy controls-were evaluated by comparing rest and dipyridamole-stress Tc-99m TF myocardial perfusion SPECT. Tc-99m TF myocardial perfusion SPECT revealed perfusion defects in 88% and 40% of the cases in groups 1 and 2, respectively. However, no cases in group 3 demonstrated myocardial perfusion defects. Tc-99m TF myocardial perfusion SPECT is a useful noninvasive imaging modality to detect cardiac involvement in SLE patients with or without cardiac symptoms and signs. (author)

  11. Striatal dopamine release in reading and writing measured with [123I]iodobenzamide and single photon emission computed tomography in right handed human subjects.

    Science.gov (United States)

    Schommartz, B; Larisch, R; Vosberg, H; Müller-Gärtner, H M

    2000-09-29

    Competition between endogenous dopamine and a radioligand for postsynaptic dopamine D(2) receptor binding was examined in two groups of eight subjects each who had to read or write off a text, respectively, and in a control group. Single photon emission computed tomography (SPECT) and the ligand [(123)I]iodobenzamide (IBZM) were used for in vivo imaging. Subjects commenced reading or writing immediately before IBZM injection and continued for 30min thereafter. SPECT images were acquired 60min later. Striatum-to-parietal-cortex IBZM uptake ratios were lower in subjects who wrote off the text than in controls indicating competition of IBZM and dopamine. There was no difference between subjects who read the text and controls. Thus, dopamine release occurs as a consequence of the motoric activity involved in writing rather than of cognitive functions necessary for reading the text.

  12. Assessment of skull base involvement in nasopharyngeal carcinoma: comparisons of single-photon emission tomography with planar bone scintigraphy and X-ray computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Lee Chianghsuan [Dept. of Nuclear Medicine, Chang Gung Memorial Hospital, Chang Gung Medical Coll., Kaohsiung (Taiwan, Province of China); Wang Peiwen [Dept. of Nuclear Medicine, Chang Gung Memorial Hospital, Chang Gung Medical Coll., Kaohsiung (Taiwan, Province of China); Chen Hueyong [Dept. of Nuclear Medicine, Chang Gung Memorial Hospital, Chang Gung Medical Coll., Kaohsiung (Taiwan, Province of China); Lui Chunchung [Dept. of Nuclear Medicine, Chang Gung Memorial Hospital, Chang Gung Medical Coll., Kaohsiung (Taiwan, Province of China); Su Chihying [Dept. of Nuclear Medicine, Chang Gung Memorial Hospital, Chang Gung Medical Coll., Kaohsiung (Taiwan, Province of China)

    1995-06-01

    The diagnostic contribution of single-photon emission tomography (SPET) to the detection of bone lesions of the skull base was explored in 200 patients with nasopharyngeal carcinoma (NPC). Comparison of SPET with planar bone scintigraphy showed that SPET improved the contrast and better defined the lesions in 107 out of the 200 patients. Comparison of SPET with X-ray computed tomography (CT) showed that SPET did not miss the lesions detected by CT while CT missed 49% of the lesions detected by SPET. The only false-positive lesion with SPET was detected in the mastoid bone. SPET detected skull base lesions in all of the 35 patients with cranial nerve involvement, while CT missed eight and planar bone scintigraphy missed four. The findings suggest that SPET should be included in the routine check-up examinations of patients with NPC. (orig.)

  13. Architecture of a Dual-Modality, High-Resolution, Fully Digital Positron Emission Tomography/Computed Tomography (PET/CT) Scanner for Small Animal Imaging

    Science.gov (United States)

    Fontaine, R.; Belanger, F.; Cadorette, J.; Leroux, J.-D.; Martin, J.-P.; Michaud, J.-B.; Pratte, J.-F.; Robert, S.; Lecomte, R.

    2005-06-01

    Contemporary positron emission tomography (PET) scanners are commonly implemented with very large scale integration analog front-end electronics to reduce power consumption, space, noise, and cost. Analog processing yields excellent results in dedicated applications, but offers little flexibility for sophisticated signal processing or for more accurate measurements with newer, fast scintillation crystals. Design goals of the new Sherbrooke PET/computed tomography (CT) scanner are: 1) to achieve 1 mm resolution in both emission (PET) and transmission (CT) imaging using the same detector channels; 2) to be able to count and discriminate individual X-ray photons in CT mode. These requirements can be better met by sampling the analog signal from each individual detector channel as early as possible, using off-the-shelf, 8-b, 100-MHz, high-speed analog-to-digital converters (ADC) and digital processing in field programmable gate arrays (FPGAs). The core of the processing units consists of Xilinx SpartanIIe that can hold up to 16 individual channels. The initial architecture is designed for 1024 channels, but modularity allows extending the system up to 10 K channels or more. This parallel architecture supports count rates in excess of a million hits/s/scintillator in CT mode and up to 100 K events/s/scintillator in PET mode, with a coincidence time window of less than 10 ns full-width at half-maximum.

  14. A Combined Experimental and Computational Fluid Dynamics Investigation of Particulate Matter Emissions from a Wall-Guided Gasoline Direct Injection Engine

    Directory of Open Access Journals (Sweden)

    Davide D. Sciortino

    2017-09-01

    Full Text Available The latest generation of high-efficiency gasoline direct injection (GDI engines continues to be a significant source of dangerous ultra-fine particulate matter (PM emissions. The forthcoming advent in the 2017–2020 timeframe of the real driving emission (RDE standards affords little time for the identification of viable solutions. The present research work aims to contribute towards a much-needed improved understanding of the process of PM formation in theoretically-homogeneous stoichiometric spark-ignition combustion. Experimental measurements of engine-out PM have been taken from a wall-guided GDI engine operated at part-load; through parallel computational fluid dynamics (CFD simulations of the test-engine, the process of mixture preparation was investigated. About 80% of the total particle number is emitted on average in the 5–50 nm range, with the vast majority being below the regulated lower limit of 23 nm. The results suggest that both improved charge homogeneity and lower peak combustion temperature contribute to lower particle number density (PNDen and larger particle size, as engine speed and load increase. The effect of engine load is stronger and results from greater injection pressure through better fuel droplet atomisation. Increases in pre-combustion homogeneity of 6% are associated with one order of magnitude reductions of PNDen. A simplified two-equation functional model was developed, which returns satisfactory qualitative predictions of PNDen as a function of basic engine control variables.

  15. The baboon model under anaesthesia for in vivo cerebral blood flow studies using single photon emission computed tomographic (SPECT) techniques

    Energy Technology Data Exchange (ETDEWEB)

    Dormehl, I.; Redelinghuys, F.; Hugo, N. [Pretoria Univ. (South Africa); Oliver, D.; Pilloy, W. [Medical Univ. of Southern Africa (MEDUNSA), Pretoria (South Africa)

    1992-12-31

    Single photon computed tomography of the brain can be useful in animal experimentation directed towards cerebral conditions. A well established and understood baboon model, necessarily under anaesthesia, could especially be valuable in such investigations. Six normal baboons were studied under various anesthetic agents and their combinations: ketamine, thiopentone, pentobarbitone and halothane. Cerebral blood flow (CBF) studies were performed with {sup 99m}Tc-HMPAO. CBF effects from various anaesthesia were detected, requiring careful choice of the anaesthesia for cerebral investigations. (author). 13 refs, 4 figs, 3 tabs.

  16. The baboon model under anaesthesia for in vivo cerebral blood flow studies using single photon emission computed tomographic (SPECT) techniques

    International Nuclear Information System (INIS)

    Dormehl, I.; Redelinghuys, F.; Hugo, N.; Oliver, D.; Pilloy, W.

    1992-01-01

    Single photon computed tomography of the brain can be useful in animal experimentation directed towards cerebral conditions. A well established and understood baboon model, necessarily under anaesthesia, could especially be valuable in such investigations. Six normal baboons were studied under various anesthetic agents and their combinations: ketamine, thiopentone, pentobarbitone and halothane. Cerebral blood flow (CBF) studies were performed with 99m Tc-HMPAO. CBF effects from various anaesthesia were detected, requiring careful choice of the anaesthesia for cerebral investigations. (author). 13 refs, 4 figs, 3 tabs

  17. Inductively coupled plasma-atomic emission spectroscopy: a computer controlled, scanning monochromator system for the rapid determination of the elements

    Energy Technology Data Exchange (ETDEWEB)

    Floyd, M.A.

    1980-03-01

    A computer controlled, scanning monochromator system specifically designed for the rapid, sequential determination of the elements is described. The monochromator is combined with an inductively coupled plasma excitation source so that elements at major, minor, trace, and ultratrace levels may be determined, in sequence, without changing experimental parameters other than the spectral line observed. A number of distinctive features not found in previously described versions are incorporated into the system here described. Performance characteristics of the entire system and several analytical applications are discussed.

  18. Comparison of cone beam SPECT with conventional SPECT by means of cardiac-thorax phantom

    International Nuclear Information System (INIS)

    McGrath, M.A.; Manglos, S.H.

    1989-01-01

    Because of poor energy characteristics of Tl-201 used for myocardial perfusion imaging, the high sensitivity of cone-beam collimation is highly desirable. Using a cardiac-thorax phantom, the authors have compared single photon emission computed tomographic (SPECT) images obtained with a cone-beam collimator to those from a parallel hole collimator commonly used for thallium studies. A water-filled circular phantom with a cardiac insert was imaged. The myocardial shell was filled with Tl-201 (220 μCi). Two solid inserts within the myocardium simulated perfusion defects. The phantom ignores truncation effects in this preliminary experiment. For the authors' collimator, the resolution was designed to be similar to the authors' all-purpose, parallel-hole collimator at 10 cm. The focal length was 50 cm. The experimental protocol was chosen to be similar to their clinical protocol. A filtered back projection algorithm was used for cone-beam data. The same algorithm was used for the parallel-hole data, but with focal length set to infinity

  19. Automatic detection of the left ventricular myocardium long axis and center in thallium-201 single photon emission computed tomography

    International Nuclear Information System (INIS)

    Cauvin, J.C.; Boire, J.Y.; Maubliant, J.C.; Bonny, J.M.; Zanca, M.; Veyre, A.

    1992-01-01

    A new method for centering and reorienting automatically the left ventricle in thallium-201 myocardial single photon emission tomography (SPECT) is proposed. The processing involves the following steps: (a) The transverse sections of the left ventricle are segmented, (b) the three-dimensional skeleton of the left ventricle is extracted using tools of mathematical morphology, (c) the skeleton is fitted to a quadratic surface by the least-squares method, (d) the left ventricle is reoriented and centered using the long axis and the coordinates of the centre of the quadratic surface. A series of 30 consecutive exercise and redistribution 201 Tl SPECT studies were centered and reoriented by two operators twice with this method, and twice manually. There was no significant difference in the mean realignment performed by the automatic and the manual methods while centering differed moderately in some instances. In all cases and for all parameters, the reproducibility of the automatic method was 1.00, while it ranged between 0.74 and 0.98 with the manual centering and reorientation. This automatic approach provides a fast and highly reproducible method for the reconstruction of short- and long-axis sections of the left ventricle in 201 Tl SPECT. (orig.)

  20. Single photon emission computed tomography procedure improves accuracy of somatostatin receptor scintigraphy in endocrine gastro-entero-pancreatic tumours

    International Nuclear Information System (INIS)

    Lebtahi, R.; Genin, R.; Rouzet, F.; Bleicner-Perez, S.; Lievre, A.; Scigliano, S.; Vialle, C.; Le Guludec, D.; Cadiot, G.; Sobhani, I.; Mignon, M.

    2005-01-01

    Somatostatin receptors scintigraphy (SRS) is a sensitive method for the detection of endocrine gastro-entero-pancreatic tumors. The aim of this study was to evaluate the sensitivity of anterior and posterior planar associated to single photon emission