ABSTRACT
UNLABELLED: Brown fat uptake of 2-deoxy-2-[F-18]fluoro-D: -glucose (FDG) on a positron emission tomography (PET) scan limits the ability to assess for cancer. Drugs such as benzodiazepine, propranolol, and reserpine have been proposed to reduce this uptake, but the studies have been either small clinical or preclinical trials. As an alternative, we evaluated the effect of controlling the patient's environmental temperature on brown fat uptake of FDG. METHOD: From January 1, 2002 to November 30, 2004, patients were identified who had (1) a pattern of FDG uptake in the neck/paravertebral areas suggestive of brown fat, (2) a repeat FDG-PET scan after control of the patient's environmental temperature, and (3) no evidence of cancer in the neck/paravertebral areas by other diagnostic methods. For the follow-up PET scan, all patients wore warm clothing and avoided exposure to cold air during their transit to our facility. After arrival, patients were kept in a separate temperature-controlled room (at least 75 degrees F) for 15 minutes to two hours before FDG injection as well as during the uptake phase. Four physicians blindly and retrospectively assessed the FDG uptake in the neck and paravertebral regions on all initial and temperature-controlled PET scans by visually grading the radioactivity on a semiquantitative scale (0 = background, 1+ = background but
Subject(s)
Adipose Tissue, Brown/diagnostic imaging , Adipose Tissue, Brown/metabolism , Fluorine Radioisotopes , Fluorodeoxyglucose F18 , Positron-Emission Tomography , Radiopharmaceuticals , Temperature , Adolescent , Adult , Female , Fluorine Radioisotopes/pharmacokinetics , Fluorodeoxyglucose F18/pharmacokinetics , Humans , Male , Middle Aged , Radiopharmaceuticals/pharmacokinetics , Retrospective StudiesABSTRACT
Heart transplant rejection is characterized pathologically by myocyte necrosis and apoptosis associated with interstitial mononuclear cell infiltration. Any one of these components can be targeted for noninvasive detection of transplant rejection. During apoptotic cell death, phosphatidylserine, a phospholipid that is normally confined to the inner leaflet of cell membrane bilayer, gets exteriorized. Technetium-99m-labeled annexin-V, an endogenous protein that has high affinity for binding to phosphatidylserine, has been administered intravenously for noninvasive identification of apoptotic cell death. In the present study of 18 cardiac allograft recipients, 13 patients had negative and five had positive myocardial uptake of annexin. These latter five demonstrated at least moderate transplant rejection and caspase-3 staining, suggesting apoptosis in their biopsy specimens. This study reveals the clinical feasibility and safety of annexin-V imaging for noninvasive detection of transplant rejection by targeting cell membrane phospholipid alterations that are commonly associated with the process of apoptosis.
Subject(s)
Annexin A5 , Graft Rejection/diagnostic imaging , Heart Transplantation/diagnostic imaging , Heart Transplantation/immunology , Organotechnetium Compounds , Radionuclide Imaging/methods , Adult , Aged , Apoptosis , Biological Transport , Female , Humans , Injections, Intravenous , Male , Middle Aged , Myocardium/immunology , Myocardium/pathologyABSTRACT
OBJECTIVES: We evaluated a novel protocol of dual-isotope, gated single-photon emission computed tomographic (SPECT) imaging combined with low and high dose dobutamine as a single test for the characterization of various types of altered myocardial dysfunction. BACKGROUND: Myocardial perfusion tomography and echocardiography have been used separately for the assessment of myocardial viability. However, it is possible to assess perfusion, function and contractile reserve using gated SPECT imaging. METHODS: We studied 54 patients with ischemic cardiomyopathy using rest and 4 h redistribution thallium-201 imaging and dobutamine technetium-99m sestamibi SPECT imaging. The sestamibi images were acquired 1 h after infusion of the maximal tolerated dose of dobutamine and again during infusion of dobutamine at a low dose to estimate contractile reserve. Myocardial segments were defined as hibernating, stunned, remodeled or scarred. RESULTS: Severe regional dysfunction was present in 584 (54%) of 1,080 segments. Based on the combination of function and perfusion characteristics in these 584 segments, 24% (n = 140) were labeled as hibernating; 23% (n = 136) as stunned; 30% (n = 177) as remodeled; and 22% (n = 131) as scarred. Contractile reserve, represented by improvement in wall motion/thickening by low dose dobutamine, was observed in 83% of stunned, 59% of hibernating, 35% of remodeled and 13% of scarred myocardial segments (p<0.05). CONCLUSIONS: It is possible with this new imaging technique to characterize dysfunctional myocardium as stunned, hibernating, remodeled and nonviable. These subtypes often coexist in the same patient.
Subject(s)
Myocardial Ischemia/diagnostic imaging , Tomography, Emission-Computed, Single-Photon/methods , Aged , Cardiotonic Agents/administration & dosage , Dobutamine/administration & dosage , Feasibility Studies , Female , Humans , Male , Middle Aged , Myocardial Stunning/diagnostic imagingABSTRACT
This study shows that in patients with intermediate pretest probability of coronary artery disease stress single-photon emission computed tomography perfusion imaging decreases the rate of coronary angiography and coronary revascularization and is economically a superior strategy to routine coronary angiography.
Subject(s)
Coronary Angiography/statistics & numerical data , Coronary Disease/diagnosis , Coronary Disease/economics , Cost of Illness , Health Resources/statistics & numerical data , Tomography, Emission-Computed, Single-Photon/statistics & numerical data , Aged , Coronary Angiography/economics , Coronary Disease/surgery , Cost Savings , Female , Humans , Male , Medicare , Middle Aged , Myocardial Revascularization , Pennsylvania , Tomography, Emission-Computed, Single-Photon/economics , Treatment Outcome , United States , Utilization ReviewABSTRACT
This study compared qualitative assessment of exercise thallium imaging to quantitative assessment in predicting outcome in 713 patients with 78% prevalence of coronary artery disease by coronary angiography; during a mean follow-up of 52 months, there were 106 hard cardiac events (death or nonfatal myocardial infarction). The qualitative method provided important prognostic information; however, unlike the quantitative technique, less patients were assigned to either the low- or high-risk group and proportionally more patients into the intermediate-risk group, which may limit the clinical usefulness of the technique.
Subject(s)
Coronary Disease/diagnostic imaging , Exercise Test , Tomography, Emission-Computed, Single-Photon/methods , Coronary Angiography , Coronary Disease/mortality , Female , Humans , Male , Middle Aged , Prognosis , Risk Factors , Survival Analysis , Thallium RadioisotopesABSTRACT
This study examined the prognostic value of single-photon emission computed tomography in angiographically high-risk patients with left main and/or 3-vessel coronary artery disease who were treated medically. Multivariable Cox survival analysis revealed the single-photon emission computed tomography score (based on size of perfusion abnormality, multivessel abnormality, left ventricular dilation, and lung uptake) as the only independent predictor of outcome.
Subject(s)
Cardiovascular Agents/therapeutic use , Coronary Angiography/methods , Coronary Disease/diagnostic imaging , Tomography, Emission-Computed, Single-Photon , Adenosine/administration & dosage , Coronary Disease/drug therapy , Electrocardiography , Exercise Test , Female , Follow-Up Studies , Humans , Injections, Intravenous , Male , Middle Aged , Observer Variation , Retrospective Studies , Thallium Radioisotopes/administration & dosage , Treatment Outcome , Vasodilator Agents/administration & dosageABSTRACT
This study showed that quantitative analysis of SPECT perfusion images provide comparable prognostic information to summed stress score in medically treated patients with coronary artery disease.
Subject(s)
Coronary Disease/mortality , Exercise Test , Tomography, Emission-Computed, Single-Photon , Coronary Angiography , Coronary Disease/diagnosis , Coronary Disease/drug therapy , Disease-Free Survival , Female , Humans , Male , Middle Aged , PrognosisABSTRACT
BACKGROUND: Left bundle branch block (LBBB) may occur with or without structural heart disease. In patients with coronary artery disease the presence of LBBB is associated with an increased risk of cardiovascular events. METHODS AND RESULTS: This study examined the outcome of 293 medically treated patients with LBBB and symptoms who were undergoing stress thallium-201 single photon emission computed tomography imaging. One hundred seventy-three men and 120 women with an age range of 67 +/- 9 years and a pretest probability of coronary artery disease of 77% +/- 28% were studied. During a mean follow-up of 33 months 58 hard cardiac events (death or nonfatal myocardial infarction) and 112 total events (hard events, coronary angioplasty, coronary bypass surgery, or cardiac transplantation) occurred. Univariate and multivariate Cox survival analysis with clinical, stress, hemodynamic, and single photon emission computed tomography variables identified the perfusion defect size (chi square = 27, p = 0.0001) and increased lung thallium uptake as the most important independent predictors of hard or total cardiac events. The hard event-free survival rate was 91% in patients with no or small defects (<15% of left ventricular myocardium) and 72% in patients with large defects (p = 0.0001, RR = 3.2, 95% CI 1.7 to 5.9). The total event-free survival rate was 81% in patients with small defects and 48% in patients with large defects (p = 0.0001, RR = 2.7, 95% CI 1.9 to 4.0). The total event rate was 54% in patients with large perfusion defects and increased lung uptake and 17% in patients with no or small abnormality and normal lung thallium uptake (p = 0.0001). CONCLUSION: Single photon emission computed tomography perfusion imaging is useful in predicting outcome in patients with LBBB and intermediate pretest probability of coronary artery disease. The size of perfusion abnormality and lung thallium uptake stratified patients into high and low risk groups with a threefold difference in hard and total cardiac events.
Subject(s)
Bundle-Branch Block/diagnostic imaging , Heart/diagnostic imaging , Tomography, Emission-Computed, Single-Photon , Aged , Coronary Circulation , Exercise Test , Female , Humans , Male , Middle Aged , PrognosisABSTRACT
Previous cases of gallium localization in various cutaneous lesions have been reported, including sporotrichosis, acne vulgaris, sarcoid, lymphoma, and exfoliative erythroderma. This is a report of a case of gallium localization in cutaneous lesions of herpes zoster.