Computed tomography (CT) is the most widely used imaging modality for cancer. CT offers good spatial resolution and low levels of statistical noise, resulting in anatomical images of high quality. However, CT detects only anatomical changes associated with the disease, functional imaging approaches are needed to image the underlying metabolic characteristics. Functional imaging using positron emission tomography (PET) using 2-[18F]fluoro-2-deoxy-D-glucose (FDG) is currently recognized as a useful imaging modality in oncology, providing valuable functional metabolic information for tumor diagnosis, staging, detecting recurrence, and monitoring response of therapy. However, PET lacks anatomical information and has a limitation in localization of small lesions and accurate definition of lesion extent and relationship with adjacent structures. To overcome the limitations of both modalities, hardware-based imaging co-registration is designed to acquire anatometabolic imaging. The advantage of fusion PET/CT includes accurate co-registration of anatomical and functional images, precise patient positioning, low noise PET attenuation correction and shortening the scan time by CT transmission. In thoracic malignant diseases, PET can allow the early and improved diagnosis by the metabolic information, and therefore better planning of the therapeutic approach. In addition, visual comparison of PET and CT improves interpretation of FDG-PET alone by precise localization or CT alone by providing metabolic information. Functional PET imaging can affect the planning target volume of radiation therapy by the precise localization and characterization of malignant lesions. In some times, combined PET/CT can guide the biopsy site of multiple equivocal lesions. I review the current roles of PET in diagnosis, staging, and therapeutic implication of patients with lung cancers
Biopsy ; Diagnosis ; Humans ; Lung Neoplasms* ; Lung* ; Noise ; Patient Positioning ; Positron-Emission Tomography ; Positron-Emission Tomography and Computed Tomography ; Recurrence

Apoptosis plays a role in the pathophysiology of many kinds of diseases and in the response of treatment. Compared to the necrosis, the apoptosis is a genetically controlled and energy-dependent process which removes the unwanted cells from the body; programmed cell death or cell suicide. During the apoptosis, phosphatidylserine is expressed in the cytoplasmic outer membrane in the early phase. Annexin V, an endogenous human protein (MW=35 kD), has an affinity of about 10 (-9) M for the phosphatidylserine exposed on the outer membrane of apoptotic cells. Annexin V can be radiolabeled with 99mTc by HYNIC or EC chelators, which can be used as an radiotracer for the in vivo imaging of apoptosis. In this article, we reviewed the apoptosis, radiolabeling of annexin V, and the experimental and clinical data using annexin V imaging.
Annexin A5 ; Apoptosis* ; Cell Death ; Chelating Agents ; Cytoplasm ; Humans ; Membranes ; Necrosis ; Suicide

Iodine-131 (I-131) has been used in the therapy of well-differentiated thyroid cancer for over 60 years and has been an important component in the management of well-differentiated thyroid cancer. Differentiated thyroid carcinoma (DTC) is one of the most curable cancers, associated with a 10-year survival rate of 80~95%. Total (or near-total) thyroidectomy followed by radioiodine ablation is considered to be the ideal treatment for the high risk tumors. The selective use of radioactive iodine on the basis of clinicopathologic features that define the risk of recurrence and disease specific mortality is generally recommended in many kinds of international or institutional guidelines. However, recurrence in the thyroid bed or cervical lymph nodes develops in 5~20% of patients with DTC and some patients develop distant metastatic disease decreasing the 10-year survival of patients by 50%. Unfortunately, many of these patients ultimately die from advanced disease and other therapeutic approaches are needed. The goals of therapy for those patients should be to improve survival, relieve symptoms, and decrease the morbidity of disease progression and limit the morbidity associated with therapy. Safe practice of radioiodine treatment should be balanced with the benefit and the risk. This review will address the results of the radioiodine treatments in patients with the advanced thyroid cancer with the recent clinical trials.
Disease Progression ; Humans ; Iodine ; Lymph Nodes ; Mortality ; Recurrence ; Survival Rate ; Thyroid Gland* ; Thyroid Neoplasms* ; Thyroidectomy

PURPOSE: We investigated reproducibility of the quantification of left ventricular volume and ejection fraction, and grading of myocardial wall motion and systolic thickening when we used gated myocardial SPECT and Cedars quantification software. MATERIALS AND METHODS: We performed gated myocardial SPECT in 33 consecutive patients twice in the same position after Tc-99m-MIBI SPECT. We used 16 frames per cycle for the gatingof sequential Tc-99m-MTBI SPECT. After reconstruction, we used Cedars quantitative gated SPECT and calculated ventricular volume and ejection fraction (EF), Wall motion was graded using 5 point score. Wall thickening was graded using 4 point score. Coefficient of variation for re-examination of volume and fraction were calculated. Kappa values (k-value) for assessing reproducibility of wall motion or wall thickening were calculated. RESULTS: Enddiastolic volumes (EDV) ranged from 58 mi to 248 ml (122 ml +/- 42 ml), endsystolic volumes (ESV) from 20 mi to 174 mi (65 ml +1- 39 ml), and EF from 20% to 68% (51% +/- 14%). Geometric mean of standard deviations of 33 patients was 5.0 ml for EDV, 3.9 ml for ESV and 1.9% for EF. Their average differences were not different from zero (p>0.05). k-value for wall motion using 2 consecutive images was 0.76 (confidence interval: 0.71-0.81). k-value was 0.87 (confidence interval:0.83-0.90) for assessment of wall thickening. CONCLUSION: We concluded that quantification of functional indices, assessment of wall motion and wall thickening using gated Tc-99m-MIBI SPECT was reproducible and we could use this method for the evaluation of short-acting drug effect.
Heart ; Humans ; Tomography, Emission-Computed, Single-Photon*

No abstract available.
Asia ; Friends ; Humans ; Theranostic Nanomedicine

PURPOSE: Either gated myocardial perfusion SPECT or attenuation corrected SPECT can be used to improve specificity in the diagnosis of coronary artery disease. We investigated in this study whether gating or attenuation correction improved diagnostic performance of rest/stress perfusion SPECT in patients having intermediate pre-test likelihood of coronary artery disease. MATERIALS AND METHODS: Sixty-eight patients underwent rest attenuation-corrected T1-20l/dipyridamole stress gated attenuation-corrected Tc-99m-MIBI SPECT using an ADAC vertex camera (M:F=29:39, aged 59+/-12 years, coronary artery stenosis> or =70%. one vessel: 13, two vessel: 18, three vessel: 8, normal: 29). Using a five-point scale, three physicians graded the post-test likelihood of coronary artery disease for each arterial territory (1 normal, 2: possibly normal 3:equivocal, 4: possibly abnormal, 5: abnormal). Sensitivity, specificity and area under receiver-operating-characteristic curves were compared for each operator between three METHODS: (A) non-attenuation-corrected SPECT; (B) gated SPECT added to (A); and (C) attenuation-corrected SPECT added to (B). RESULTS: When grade 3 was used as the criteria for coronary artery disease, no differences in sensitivity and specificity were found between the three methods for each operator Areas under receiver- operating-characteristic curves for diagnosis of coronary artery disease revealed no differences between each modality (p>005). CONCLUSION: In patients at intermediate risk of coronary artery disease, gated SPECT and attenuation-corrected SPECT did not improve diagnostic performance.
Coronary Artery Disease* ; Coronary Vessels* ; Diagnosis ; Humans ; Perfusion* ; ROC Curve ; Sensitivity and Specificity ; Tomography, Emission-Computed, Single-Photon*

BACKGROUND AND OBJECTIVES: We investigated if gated and/or attenuation-corrected SPECT improved performance of experienced or in-experienced operators in the diagnosis of coronary artery disease (CAD) or stenosed arteries in patients having intermediate or high pretest likelihood. MATERIALS AND METHODS: Rest/dipyridamole stress gated attenuation-corrected SPECT was performed in 81 patients (M:F=48:33, 62+/-8.6 years old, of high (n=38) or intermediate (n=43) pre-test likelihood for CAD, 1 vessel; 14, 2 vessel; 19, 3 vessel disease; 31, normal; 17). Two experienced and one novice physicians graded 1 (normal) to 5 (definitely abnormal) for each artery 1) by conventional rest Tl-201/stress Tc-99m-MIBI SPECT, 2) 1) plus viewing gated SPECT (+gated) and 3) 2) plus attenuation-corrected SPECT (+AC gated). Areas under curves (AUC) of receiver operating characteristic (ROC) curves were compared. RESULTS: AUC was greater in patients with high likelihood than intermediate likelihood. Novice physician performed better in diagnosing RCA stenosis (AUC: 0.53 for usual, 0.58 for +gated, and 0.66 for +AC gated) in patients with intermediate likelihood. AUC was not different for the diagnosis of CAD and LAD or LCx. Performance of experienced physicians was not different regardless of pre-test likelihood. Novice operator's specificity increased from 53% to 73% for CAD, and 62% to 89% (p<0.05) for RCA in patients with intermediate likelihood. CONCLUSION: We conclude that gated attenuation-corrected SPECT was helpful only for novice physician to diagnose RCA stenosis by increasing specificity in patients with intermediate likelihood. Even for inexperienced physician, these methods were not helpful in patients with high pre-test likelihood or for LAD or LCX.
Area Under Curve ; Arteries ; Constriction, Pathologic ; Coronary Artery Disease* ; Coronary Vessels* ; Diagnosis ; Humans ; ROC Curve ; Sensitivity and Specificity ; Tomography, Emission-Computed, Single-Photon*

Iodide uptake across the membranes of thyroid follicular cells and cancer cells occurs through an active transport process mediated by the sodium-iodide symporter (NIS). The rat and human NIS-coding genes were cloned and identified in 1996. Evaluation of NIS gene and protein expression is critical for the management of thyroid cancer, and several approaches to increase NIS levels have been tried. Identification of the NIS gene has provided a means of expanding its role in radionuclide therapy and molecular target-specific theragnosis (therapy and diagnosis using the same molecular target). In this article, we describe the relationship between NIS expression and the thyroid carcinoma treatment using I-131 and alternative therapeutic approaches.
Animals ; Biological Transport, Active ; Clone Cells ; Diagnosis ; Humans ; Ion Transport ; Membranes ; Rats ; Thyroid Gland ; Thyroid Neoplasms*

Artifact corrections including normalization and attenuation correction were important for quantitative analysis in Nuclear Medicine Imaging. Normalization is the process of ensuring that all lines of response joining detectors in coincidence have the same effective sensitivity. Failure to account for variations in LOR sensitivity leads to bias and high-frequency artifacts in the reconstructed images. Attenuation correction is the process of the correction of attenuation phenomenon lies in the natural property that photons emitted by the radiopharmaceutical will interact with tissue and other materials as they pass through the body. In this paper, we will review the several approaches for normalization and attenuation correction strategies.
Artifacts ; Bias (Epidemiology) ; Enzyme Multiplied Immunoassay Technique ; Nuclear Medicine ; Photons