Comparison Of Positron Emission Tomography Research Articles

Prospective comparison of positron emission tomography (PET)/magnetic resonance and PET/computed tomography dosimetry in hepatic malignant neoplastic disease after 90Y radioembolization treatment.

90Y radioembolization is an established treatment modality for hepatic malignancies. Successful radioembolization requires optimal dose delivery to tumors while minimizing dosages to parenchyma. Post-treatment positron emission tomography (PET)/computed tomography (CT) dosimetry is the established benchmark, whereas PET/magnetic resonance (MR) is an emerging modality. The goal of this study was to assess the intermodality agreement between PET/MR and PET/CT 90Y dosimetry. In this single-institution study, 18 patients (20 treatment sessions) with a primary or metastatic hepatic malignancy underwent both PET/MR and PET/CT after 90Y radioembolization. Patients were randomized to undergo one modality first, followed by the other. The region of interest was delineated using MR images and tumor and liver dosimetry was calculated. Intermodality agreement was assessed using the Bland-Altman method. A generalized linear model was used to assess the effect of baseline variables on intermodality dose differences. PET/MR underestimated tumor and liver absorbed doses when compared to PET/CT by -3.7% (P=0.042) and -5.8% (P=0.029), respectively. A coverage probability plot demonstrated that 80% and 90% of tumor dose measurements fell within intermodality differences of 11% and 18%, respectively. PET/MR underestimated tumor dose at both low (<1 GBq) and high (>3 GBq) injected activity levels (P<0.001) by -22.3 [standard deviation (SD) =13.5] and -24.3 (SD =18.7), respectively. Although PET/MR significantly underestimated the absorbed dose when compared to PET/CT, the intermodality agreement was high and the degree of underestimation was better than previously reported. Intermodality differences were more pronounced at low and high injected doses. Additional studies are required to assess the clinical implications of these findings.

Comparison of positron emission tomography with computed tomography examination with histopathological assessment of pelvic lymph nodes in patients with cervical cancer treated surgically.

IntroductionAccording to the literature, fluor-18-fluorodeoxyglucose positron emission tomography with computed tomography (18F-FDG-PET-CT) is the most effective technique for the examination and detection of metastases in the lymph nodes in patients with cervical cancer. This study aimed to compare the diagnostic value of the preoperative evaluation using 18F-FDG-PET-CT with a histopathological examination of the lymph nodes removed during radical hysterectomy and pelvic lymph node dissection in patients with cervical cancer.Material and methodsRetrospective analysis covered the medical records of 42 patients with cervical cancer (stage IA–IB according to International Federation of Gynaecology and Obstetrics 2009) treated with radical Piver type III hysterectomy and pelvic lymph node dissection. The preoperative diagnosis was made using a PET/CT examination. Results: The result of the 18F-FDG-PET-CT examination highlighted a suspicion of lymph node metastases in 13 patients (31%). The histopathological examination confirmed this in 12 patients (29%). Metastatic lymph nodes were correctly diagnosed using 18F-FDG-PET-CT in 8 out of the 12 cases confirmed by the histopathological examination. In the patient-based study, sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 66.8%, 83.3%, 61.5%, 86.2 % and 78.6%, respectively.ConclusionsWe confirmed the usefulness of PET in the preoperative assessment of cervical cancer advancement, especially in correlation with the new 2018 International Federation of Gynaecology and Obstetrics staging system.

Ethnic Disparities inImaging Utilization at Diagnosis of Non-Small Cell Lung Cancer.

Prior research demonstrated statistically significant racial disparities related to lung cancer treatment and outcomes. We examined differences in initial imaging and survival between blacks, Hispanics, and non-Hispanic whites. The linked Surveillance, Epidemiology, and End Results-Medicare database between 2007 and 2015 was used to compare initial imaging modality for patients with lung cancer. Participants included 28 881 non-Hispanic whites, 3123 black, and 1907 Hispanics, patients age 66 years and older who were enrolled in Medicare fee-for-service and diagnosed with lung cancer. The primary outcome was comparison of positron emission tomography (PET) imaging with computerized tomography (CT) imaging use between groups. A secondary outcome was 12-month cancer-specific survival. Information on stage, treatment, and treatment facility was included in the analysis. Chi-square test and logistic regression were used to evaluate factors associated with imaging use. Kaplan-Meier method and Cox proportional hazards regression were used to calculate adjusted hazard ratios and survival. All statistical tests were two-sided. After adjusting for demographic, community, and facility characteristics, blacks were less likely to undergo PET or CT imaging at diagnosis compared with non-Hispanic whites odds ratio (OR) = 0.54 (95% confidence interval [CI] = 0.50 to 0.59; P < .001). Hispanics were also less likely to receive PET with CT imaging (OR = 0.72, 95% CI = 0.65 to 0.81; P < .001). PET with CT was associated with improved survival (HR = 0.61, 95% CI = 0.57 to 0.65; P < .001). Blacks and Hispanics are less likely to undergo guideline-recommended PET with CT imaging at diagnosis of lung cancer, which may partially explain differences in survival. Awareness of this issue will allow for future interventions aimed at reducing this disparity.

Bone marrow involvement in pediatric malignancies: a comparison study of Positron emission tomographycomputed tomography and bone marrow biopsy

The comparison of Positron emission tomography- computed tomography (PETCT) and bone marrow biopsy (BMB) modalities in detecting bone marrow disease is an up to date research topic. In this study, we aimed to compare the results of PET-CT and BMB procedures in detecting bone marrow involvement in pediatric malignancies. At the time of diagnosis, PET-CT imaging and BMB performed patients` data were evaluated, retrospectively. Malign diagnoses were Hodgkin's lymphoma in 23 (30.7%), non-Hodgkin's lymphoma in 20 (26.7%), neuroblastoma in 11 (14.7%), Ewing sarcoma in 10 (13.7%), Langerhans cell histiocytosis in 6 (8%), and rhabdomyosarcoma in 5 (6.6%) patients. Bone marrow involvement was detected in 39 (52%) of 75 patients. Bone marrow involvement was identified by both PET-CT and BMB in 18 (46.1%) patients, by only PET-CT in 12 (30.7%) patients, by only BMB in 9 (23%) patients. The sensitivity of PET-CT was 66%, specificity was 75%, positive predictive value was 60%, and negative predictive value was 80%. Sensitivity, spesificity, positive and negative predictive values of PETCT were different in before mentioned malignancy groups. PET-CT may not have high sensitivity and specificity to identify bone marrow involvement for each type of cancer. The approach of using bone marrow biopsy and PET-CT as complementary modalities seems reliable.

SURGICAL TREATMENT OF MRI-NEGATIVE EPILEPSY (A REVIEW)

Removal of epileptogenic lesions is an effective way to treat patients with drug-resistant epilepsy. The result of surgical treatment depends on the correct detection of pathology, definition of its boundaries. No lesion on magnetic resonance imaging is not a contraindication to surgical treatment, but requires a survey. Each of the additional methods has its advantages and disadvantages. Сomprehensive examination, analysis and comparison of positron emission tomography, single-photon emission computed tomography, magnetoencephalography, scalp and invasive electroencephalography data can significantly improve the results of surgical treatment MRI-negative epilepsy patients. Clarification of the pre-surgical evaluation algorithm will allow to optimize the use of techniques.

Comparison of Positron Emission Tomography Using 2-[18F]-fluoro-2-deoxy-D-glucose and 3-deoxy-3-[18F]-fluorothymidine in Lung Cancer Imaging.

Background:The detection of solitary pulmonary nodules (SPNs) that may potentially develop into a malignant lesion is essential for early clinical interventions. However, grading classification based on computed tomography (CT) imaging results remains a significant challenge. The 2-[18F]-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography (PET)/CT imaging produces both false-positive and false-negative findings for the diagnosis of SPNs. In this study, we compared 18F-FDG and 3-deoxy-3-[18F]-fluorothymidine (18F-FLT) in lung cancer PET/CT imaging.Methods:The binding ratios of the two tracers to A549 lung cancer cells were calculated. The mouse lung cancer model was established (n = 12), and micro-PET/CT analysis using the two tracers was performed. Images using the two tracers were collected from 55 lung cancer patients with SPNs. The correlation among the cell-tracer binding ratios, standardized uptake values (SUVs), and Ki-67 proliferation marker expression were investigated.Results:The cell-tracer binding ratio for the A549 cells using the 18F-FDG was greater than the ratio using 18F-FLT (P < 0.05). The Ki-67 expression showed a significant positive correlation with the 18F-FLT binding ratio (r = 0.824, P < 0.01). The tumor-to-nontumor uptake ratio of 18F-FDG imaging in xenografts was higher than that of 18F-FLT imaging. The diagnostic sensitivity, specificity, and the accuracy of 18F-FDG for lung cancer were 89%, 67%, and 73%, respectively. Moreover, the diagnostic sensitivity, specificity, and the accuracy of 18F-FLT for lung cancer were 71%, 79%, and 76%, respectively. There was an obvious positive correlation between the lung cancer Ki-67 expression and the mean maximum SUV of 18F-FDG and 18F-FLT (r = 0.658, P < 0.05 and r = 0.724, P < 0.01, respectively).Conclusions:The 18F-FDG uptake ratio is higher than that of 18F-FLT in A549 cells at the cellular level. 18F-FLT imaging might be superior for the quantitative diagnosis of lung tumor tissue and could distinguish lung cancer nodules from other SPNs.

A Comparison of Positron Emission Tomography and Colonoscopy for the Detection of Advanced Colorectal Neoplasms in Subjects Undergoing a Health Check-Up

Background & AimsThere is no agreement as to whether F-18 fluorodeoxyglucose positron emission tomography and computed tomography (FDG PET/CT) screening for advanced colorectal neoplasms is meaningful. This retrospective study was undertaken to determine whether FDG PET/CT may be a valuable screening tool for the detection of advanced colorectal neoplasms.MethodsA retrospective review of the records of 1,109 FDG PET/CT scans acquired from January 2007 to December 2011 was performed. Colonoscopy and FDG PET/CT imaging were performed within two days of each other. The results of colonoscopy were taken as the gold standard, either with or without the results of the histopathological examination. An advanced neoplasm was defined as the presence of a malignant tumor, an adenoma ≥1 cm, or histological evidence of high-grade dysplasia or significant villous components.ResultsA total of 36 subjects had advanced colorectal neoplasms detected by colonoscopy (totaling 38 neoplasms). Six of the 38 neoplasms were also detected by FDG PET/CT. The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of FDG PET/CT in the detection of advanced colorectal neoplasms were 15.8% (6/38), 99.1% (1063/1073), 37.5% (6/16), 97.1% (1063/1095), and 96.2% (1069/1111) respectively. The presence of lesions with an endoscopic size ≤1.5 cm (P<0.001) and low-grade dysplasia (P<0.001) were the main predictors of false-negative FDG PET/CT findings.ConclusionsWe conclude that FDG PET/CT screening of advanced colorectal neoplasms is unwarranted, especially in the presence of lesions with an endoscopic size ≤1.5 cm or low-grade dysplasia.

Comparison of positron emission tomography (PET) and computed tomography (CT) for better target volume definition in radiation therapy planning

In cancer patients, positron emission tomography/ computed tomography (PET/CT) fused images present less variability in target contouring, respect to use only CT images, respectively. However, the gold standard has not yet been clearly established between radiation oncologists with regard to PET images and the methodology of contouring targets with confidence using PET/CT fused images. The aim of this study was to determine whether integrated PET/CT fused images provide advantages in virtual simulation compared with morphological contouring only with CT. Thirty cancer patients were evaluated in an adapted PET/CT hybrid in radiotherapy (RT) setup position, with 20 of them being suitable for RT: 17 were suitable for curative intent, which was the group of interest in this study. All image series were sent to the RT work station (WS) where CT and PET series were automatically fused by Digital Imaging and Communications in Medicine (DICOM) in each case. PET series were threshold and were subjected to source-to-background contrast algorithms to fi nally redefine the original tumour description. Three different radiotherapy plans (RTP) for each patient were compared after targets were contoured: [1] planning over metabolic (PET) contoured targets, [2] planning over only morphologic (CT) targets, and [3] planning over targets obtained for treatment based on fused PET/CT images. PET/CT findings altered initial-stage planning in four patients (23.5%) because they had been undergoing chemotherapy. Gross target volume (GTV) and planning target volume (PTV) based only on PET showed more homogeneity to obtain mean doses (p = 0.025) with respect to those based on PET/CT, respectively. However, no percentage differences were observed in median PTV doses between the planning methods, although there was higher variability in PET/CT planning. Morphological (CT) and PET/ CT target volumes were more voluminous than metabolic (PET) volumes. On the other hand, 20% of metabolic (PET) PTV were out of those defined by PET/CT. Thoracic RT plans based on PET preserved better bilateral lung [percentage volume of lung irradiated with a dose of 20 Gy (V20); significance, R(2) = 0.559, p = 0.006]. For our physicians, PET/CT fused images allowed better contouring of primary tumours in 40% of head and neck cancers and 34% of thoracic cancers. PET/CT provides useful information for virtual simulation therapy. Image treatment and planning in an RT workstation is mandatory.

Detection of nodal metastatic disease in patients with non-small cell lung cancer: comparison of positron emission tomography (PET), contrast-enhanced computed tomography (CT), and combined PET-CT

Of 31 patients with lung cancer, 19 underwent PET-CT and 12 had CT followed by PET. Thoracic lymph nodes were sampled by mediastinoscopy or thoracotomy. Sensitivities, specificities, positive (PPV), and negative predictive values (NPV) were calculated based on histopathology. Ninety nodes (41 malignant) were identified. Sensitivity, specificity, PPV, and NPV were 94%, 73%, 66%, and 96% for PET-CT, respectively. In 12 patients who underwent PET and CT separately, these values were 90%, 31%, 64%, and 71% for PET and 81%, 50%, 69%, and 66% for CT, respectively.

Comparison of Positron Emission Tomography and X-ray radiography for studies of physical processes in sandstone

The migration of moisture in cores of porous homogeneous sandstone of Ledian age (Belgian Eocene, Tertiary) is monitored with PET ( Positron Emission Tomography) and micro-focus X-ray radiography. In the case of PET, a nuclear medical imaging technique, 55Co-EDTA ( Ethylene diamine Tetra acetic acid) and R- 18F were used as water-soluble tracers. The X-ray projection method has evolved from the better-known medical technique and allows a fast and accurate determination of the two-dimensional transient moisture content profiles. Results indicate that both techniques can deliver important information concerning physical processes in situ.

Comparison of positron emission tomography and lymphangiography in the diagnosis of infradiaphragmatic hodgkin's disease

To evaluate the respective roles of positron emission tomography using 18F-fluorodeoxyglucose (FDG-PET) and lymphangiography (LAG) in staging Hodgkin's disease (HD) patients with negative contrast-enhanced infradiaphragmatic computed tomography (CT). 28 patients underwent FDG-PET and LAG at initial staging. Concordant positive findings on both tests were regarded as actual HD locations and concordant negative findings as true negative. In case of discrepancy, the reference was biopsy or magnetic resonance imaging (MRI). Concordant results were obtained in 26 patients (24 negative, two positive). In two of the 24 negative patients, PET showed additional lesions in the spleen and one celiac lymph node (one patient), and in the right kidney and the right iliac crest (one patient). Discordant results were obtained in two patients. Both methods indicated infradiaphragmatic involvement in different locations in one patient. In the other, PET was falsely positive (PET done within 24 hours after a negative LAG), which was confirmed by biopsy (benign inflammatory, probably due to LAG medium). FDG-PET and LAG gave comparable results, making invasive LAG unnecessary. Furthermore, LAG, when performed before PET, can be responsible for false-positive PET results.

Comparison of Positron Emission Tomography and Computed Tomography for the Detection of Cervical Lymph Node Metastases of Oral Squamous Cell Carcinoma

Objective: To investigate the use of positron emission tomography for the detection of cervical metastases of oral squamous cell carcinoma.Materials and Methods: Twenty four patients with histologically confirmed oral squamous cell carcinoma, without previous surgery, radiation therapy, or chemotherapy, and with pretreatment computed tomography and positron emission tomography scans, were included. In this retrospective chart review, data were collected for computed tomography and positron emission tomography findings, treatment, and outcomes. The findings for computed tomography, positron emission tomography, and histopathology were analysed by paired Fisher's exact t test.Results: A statistically significant correlation was noted between computed tomography and positron emission tomography findings (p = 0.033) as judged by the histopathology results of 8 neck dissections. No correlation was found between computed tomography findings or positron emission tomography and histopathology. Among the 14 patients with positive computed tomography and positron emission tomography scans, 9 were ultimately documented to have cervical metastases. Among the 6 patients with negative computed tomography and positive positron emission tomography, 5 had neck lymph node metastases (p = 0.048) during followup, while patients with negative positron emission tomography did not show neck metastases.Conclusion: In comparison with conventional computed tomography, positron emission tomography provided additional information for the detection of cervical lymph node metastases of oral squamous cell carcinoma. The importance of positron emission tomography for the early detection of neck lymph node metastases is emphasised.

Comparison of Positron Emission Tomography, Computed Tomography, and Endoscopic Ultrasound in the Initial Staging of Patients with Esophageal Cancer

Improvement in esophageal cancer staging is needed. Positron emission tomography (PET), computed tomography (CT), and endoscopic ultrasound (EUS) in the staging of esophageal carcinoma were compared. PET, CT, and EUS were performed and interpreted prospectively in 75 patients with newly diagnosed esophageal cancer. Either tissue confirmation or fine needle aspiration (FNA) was used as the gold standard of disease. Sensitivity and specificity for tumor, nodal, and metastatic (TNM) disease for each test were determined. TNM categorizations from each test were used to assign patients to subgroups corresponding to the three treatment plans that patients could theoretically receive, and these were then compared. Local tumor staging (T) was done correctly by CT and PET in 42% and by EUS in 71% of patients (P value > 0.14). The sensitivity and specificity for nodal involvement (N) by modality were 84% and 67% for CT, 86% and 67% for EUS, and 82% and 60% for PET (P value > 0.38). The sensitivity and specificity for distant metastasis were 81% and 82% for CT, 73% and 86% for EUS, and 81% and 91% for PET (P value > 0.25). Treatment assignment was done correctly by CT in 65%, by EUS in 75%, and by PET in 70% of patients (P value > 0.34). EUS had superior T staging ability over PET and CT in our study group. The tests showed similar performance in nodal staging and there was a trend toward improved distant disease staging with CT or PET over EUS. Assignment to treatment groups in relation to TNM staging tended to be better by EUS. Each test contributed unique patient staging information on an individual basis.

Mediastinal lymph node staging in suspected lung cancer: comparison of positron emission tomography with F-18-fluorodeoxyglucose and mediastinoscopy

BackgroundIn patients with bronchogenic carcinoma, mediastinal lymph node staging is essential for determining treatment options. In this retrospective analysis we compared the results of positron emission tomography (PET) using F-18 fluorodeoxyglucose with those of mediastinoscopy in nodal staging for suspected bronchogenic carcinoma. MethodsFrom March 1997 to June 2001, 102 patients (86 male,16 female, age 62 ± 9 years) underwent both PET and mediastinoscopy for radiologically suspected mediastinal lymph node disease in bronchogenic carcinoma. Total body emission scans were acquired 90 to 150 minutes after injection of 230 MBq of F-18 fluorodeoxyglucose. Mediastinoscopic evaluation of lymph node stations was performed according to the method of Mountain and Dresler (1R,1L, 2L, 2R, 4L, 4R,7). Patients were eligible if surgical staging was performed within 6 weeks after the PET scan. ResultsOf the 102 patients, benign lesions were diagnosed in 15. In 87 patients malignant disease was proven by histology, and bronchogenic carcinoma was found in 82. Of 469 nodal stations analyzed, malignancy was documented by histology in 84. In PET analysis 79 true-positive and 304 true-negative samples were found. Five lymph node stations were false negative, and 81 samples were false positive. False-positive findings in PET frequently were seen in inflammatory lung disease. The sensitivity of PET was 94.1%, specificity was 79% with a diagnostic accuracy of 81.6%. The positive predictive value of PET was 49.3%, and the negative predictive value was 98.4%. ConclusionsIn patients with positive PET scan results histologic verification appears necessary for exact lymph node staging. In view of the negative predictive value mediastinoscopy can be omitted in patients with bronchogenic carcinoma whose PET scan results were negative.

FDG-PET for detection of pulmonary metastases from malignant primary bone tumors: Comparison with spiral CT

The purpose was the comparison of positron emission tomography using F-18-fluorodeoxy-glucose (FDG-PET) and spiral thoracic CT to detect pulmonary metastases from malignant primary osseous tumors. In 71 patients with histologically confirmed malignant primary bone tumors (32 osteosarcomas, 39 Ewing's sarcomas) 111 FDG-PET examinations were evaluated with regard to pulmonary/pleural metastases in comparison with spiral thoracic CT. Reference methods were the clinical follow-ups for 6-64 months (median 20 months) or a histopathologic analysis. In 16 patients (23%) reference methods revealed a pulmonary/pleural metastatic disease. FDG-PET had a sensitivity of 0.50, a specificity of 0.98, and an accuracy of 0.87 on a patient based analysis. Comparable values for spiral CT were 0.75, 1.00, and 0.94. It was shown that no patient who had a true positive FDG-PET had a false negative CT scan, nor was a pulmonary metastases detected earlier by FDG-PET than by spiral CT. There seems to be a superiority of spiral CT in the detection of pulmonary metastases from malignant primary bone tumors as compared with FDG-PET. Therefore, at present a negative FDG-PET cannot be recommended to exclude lung metastases. However, as specificity of FDG-PET is high, a positive FDG-PET result can be used to confirm abnormalities seen on thoracic CT scans as metastatic.

Comparison of positron emission tomography, cognition, and brain volume in Alzheimer's disease with and without severe abnormalities of white matter.

To examine cerebral metabolism, cognitive performance, and brain volumes in healthy controls and two groups of patients with probable Alzheimer's disease, one group with severe abnormalities of white matter (DAT+) and the other group with none, or minimal abnormalities (DAT-). Neuropsychological tests, CT, MRI, quantitative MRI, and PET studies were carried out to allow comparison between the DAT+ and DAT- groups and the healthy controls. Compared with the healthy controls, both demented groups had significantly reduced global and regional cerebral metabolism, significant brain atrophy, and significantly lower scores on neuropsychological testing. The DAT- patient group showed a pattern of parietal-temporal cerebral metabolic reductions and neuropsychological performance deficits typical of Alzheimer's disease. In addition, metabolism in the association neocortex (AD ratio) and measures of neuropsychological task performance were significantly correlated in the DAT- patient group. Comparison of DAT+ with DAT- patients showed a significantly higher ratio of parietal to whole brain glucose utilisation for the DAT+ group. Moreover, when comparing group z score differences from the healthy controls, the DAT+ group had, on average, smaller differences from controls in the frontal, parietal, and temporal regions than did the DAT- group. Discriminant analysis using metabolic ratios of the frontal, parietal, and temporal regions showed cerebral metabolic patterns to be significantly different among the DAT+, the DAT-, and the healthy controls. These differences were due primarily to relatively higher frontal, parietal, and temporal metabolic ratios in the DAT+ group which resulted in discriminant scores for the DAT+ group between the healthy controls and the DAT- group. Group mean scores on tests of neuropsychological performance were not significantly different between the DAT- and DAT+ patients. By contrast with the DAT- group, however, no significant correlations between the AD ratio and any neuropsychological task were seen in the DAT+ group. Multiple regression analysis showed significant between group differences in the relation between the AD ratio and neuropsychological scores on three tasks. The slopes of the relations between the AD ratio and memory scores (memory and freedom from distractability deviation quotient of the Wechsler adult intelligence scale (WMDQ)) also were significantly different for the two groups. Although multiple causes for abnormalities of white matter exist in patients with Alzheimer's disease, these data suggest that the presence of severe abnormalities of white matter indicate a second pathological process in the DAT+ patients. The DAT- patients showed the parietal-temporal metabolic deficits and correlations between association neocortical metabolism and neuropsychological task performance typical of patients with Alzheimer's disease. By contrast, the DAT+ group had a pattern of cerebral metabolism significantly different from healthy controls and DAT+ patients, as well as no significant correlations between metabolism in the association neocortex and neuropsychological performance. These differences probably reflect the superimposed pathology of the abnormalities of white matter which may exert their affect through disruption of long corticocortical pathways.

Identification of recurrent ischemia after coronary artery bypass surgery: a comparison of positron emission tomography and single photon emission computed tomography

Current techniques for the detection of recurrent coronary stenoses following bypass grafting have shown disappointing diagnostic accuracy. This study used the same dipyridamole-handgrip stress to compare the accuracy of rubidium-82 positron emission tomography and thallium-201 single photon emission computed tomography, in 50 consecutive post-bypass patients undergoing coronary arteriography at a mean interval of 6.5 years after surgery. Significant stenoses in native coronary vessels (> 50% diameter) or grafts (> 70% diameter) were defined by quantitative angiography. Forty-six patients had recurrent or residual stenoses, 43 (93%) had a perfusion defect identified by positron emission tomography, and 35 (76%) were identified by single photon emission computed tomography ( P = 0.04). Fourteen of the 17 patients (82%) without previous Q-wave myocardial infarction were identified by positron emission tomography; 10 of the 17 (59%) were detected by single photon emission computed tomography ( P = NS). Stress-induced perfusion defects were demonstrated by positron emission tomography in 19 patients; of this group, thallium imaging identified reversible defects in 11, showed no perfusion defect in 1, and portrayed a persistent defect in 7 patients. Significant graft disease was present in 33 patients; perfusion defects were identified by positron emission tomography in 30 (91%), and by single photon emission computed tomography in 24 (73%, P = NS). Four patients were fully revascularized, without significant recurrent coronary disease; normal perfusion was present in 3 (75%) by positron emission tomography, and 4 (100%) by single photon emission computed tomography. Myocardial perfusion imaging using positron emission tomography has a high accuracy for the detection of both graft and native vessel disease, and may be useful in the non-invasive follow-up of patients following coronary artery bypass grafting.

Comparison of positron emission tomography using C-11 acetate with F-18 fluorodeoxyglucose in predicting myocardial viability

Comparison of positron emission tomography using C-11 acetate with F-18 fluorodeoxyglucose in predicting myocardial viability

Cerebral involvement in systemic lupus erythematosus (SLE): Comparison of positron emission tomography (PET) with other imaging methods

Observation chez 10 patients. Les manifestations cliniques sont a type d'infarctus cerebraux, troubles mentaux et epilepsie. La PET montre un deficit d'utilisation du glucose. L'imagerie RMN detecte des lesions focales et medullaires