• Proceedings of the Korean Nuclear Society Conference
• /
• 1999.05a
• /
• pp.403-403
• /
• 1999

• Journal of radiological science and technology
• /
• v.29 no.4
• /
• pp.249-255
• /
• 2006

Purpose: The diagnostic utility of fluorine-18 2-deoxy-D-glucose positron emission tomograhpy ($^{18}F-FDG $PET) for the non-invasive differentiation of focal lung lesions originated from cancer or inflammation disease by combined visual image interpretation and semi-quantitative uptake value analysis has been documented. In general, Standardized Uptake Value(SUV) is used to diagnose lung disease. But SUV does not contain dynamic information of lung tissue for the glucose. Therefore, this study was undertaken to hypothesis that analysis of dynamic kinetics of focal lung lesions base on $^{18}F-FDG$ PET may more accurately determine the lung disease. So we compared Time Activity Curve(TAC), Standardized Uptake Value-Dynamic Curve(SUV-DC) graph pattern with Glucose Metabolic Rate(MRGlu) from Patlak analysis. Methods: With lung disease, 17 patients were examined. They were injected with $^{18}F-FDG$ over 30-s into peripheral vein while acquisition of the serial transaxial tomographic images were started. For acquisition protocol, we used twelve 10-s, four 30-s, sixteen 60-s, five 300-s and one 900-s frame for 60 mins. Its images were analyzed by visual interpretation TAC, SUV-DC and a kinetic analysis(Patlak analysis). The latter was based on region of interest(ROIs) which were drawn with the lung disease shape. Each optimized patterns were compared with itself. Results: In TAC patterns, it hard to observe cancer type with inflammation disease in early pool blood area but over the time cancer type slope more remarkably increased than inflammation disease. SUV-DC was similar to TAC pattern. In the result of Patlak analysis, In time activity curve of aorta, even though inflammation disease showed higher blood activity than cancer, at first as time went by, blood activity of inflammation disease became the lowest. However, in time activity curve of tissue, cancer had the highest uptake and inflammation disease was in the middle. Conclusion: Through the examination, TAC and SUV-DC could approached the results that lung cancer type and inflammation disease type has it's own difference shape patterns. Also, it has outstanding differentiation between cancer type and inflammation in Patlak and MRGlu analysis. Through these analysis methods, it will helpful to separation lung disease.

• Nuclear Medicine and Molecular Imaging
• /
• v.41 no.4
• /
• pp.317-325
• /
• 2007

Purpose: Biological parameters can be quantified using dynamic PET data with compartment modeling and Nonlinear Least Square (NLS) estimation. However, the generation of parametric images using the NLS is not appropriate because of the initial value problem and excessive computation time. In irreversible model, Patlak graphical analysis (PGA) has been commonly used as an alternative to the NLS method. In PGA, however, the start time ($t^*$, time where linear phase starts) has to be determined. In this study, we suggest a new Multiple Linear Analysis for irreversible radiotracer (MLAIR) to estimate fluoride bone influx rate (Ki). Methods: $[^{18}F]Fluoride$ dynamic PET scans was acquired for 60 min in three normal mini-pigs. The plasma input curve was derived using blood sampling from the femoral artery. Tissue time-activity curves were measured by drawing region of interests (ROls) on the femur head, vertebra, and muscle. Parametric images of Ki were generated using MLAIR and PGA methods. Result: In ROI analysis, estimated Ki values using MLAIR and PGA method was slightly higher than those of NLS, but the results of MLAIR and PGA were equivalent. Patlak slopes (Ki) were changed with different $t^*$ in low uptake region. Compared with PGA, the quality of parametric image was considerably improved using new method. Conclusion: The results showed that the MLAIR was efficient and robust method for the generation of Ki parametric image from $[^{18}F]Fluoride$ PET. It will be also a good alternative to PGA for the radiotracers with irreversible three compartment model.

• Proceedings of the Korean Society of Medical Physics Conference
• /
• 2002.09a
• /
• pp.314-317
• /
• 2002

The purpose of this study was to evaluate the clinical application of Patlak tool on GE PET workstation for quantitative analysis of dynamic PET images in cardiac patients. Three patients including coronary artery disease (CAD), myocardial infarction (MI), and angina were studied. All subjects underwent dynamic cardiac PET scan using a GE Advance scanner. After 10 min transmission scan for attenuation correction using two rotating $\^$68/Ge rod sources, three patients with cardiac disease were performed dynamic cardiac PET scan after the administration of approximately 370 MBq of FDG. The dynamic scan consisted of 36 frames with variable frame length (12${\times}$10s, 6${\times}$20s, 6${\times}$60s, 12${\times}$300s) for a total time of 70 min. Blood samples were obtained to determine the plasma substrate concentration. Region of interest of circular and rectangular shape to acquire input functions and tissue data were placed on left ventricle and myocardium. A value of 0.67 was used for lumped constant. Mean plasma substrate concentrations for three patients were 100 mg/dl (CAD), 100 mg/dl (MI), 132 mg/dl (angina), respectively. Regional MMRGlc values (mean${\pm}$SD) at lateral myocardium area for CAD, MI, and angina were 8.43${\pm}$0.24, 4.08${\pm}$0.16, and 6.15${\pm}$0.23 mg/min/100ml, respectively. Patlak tool on GE PET workstation appeared to be useful for quantitative analysis of dynamic PET images in cardiac patients, although further studies may be required for absolute quantitation.

• Journal of Veterinary Clinics
• /
• v.29 no.2
• /
• pp.130-133
• /
• 2012

The purpose of this study is to assess the relationship between glomerular filtration rate (GFR) and age by using dynamic computed tomography (CT) and Patlak plot analysis in dogs. Fifteen dogs were used in this study. CT-GFR study was performed under general anesthesia using propofol and isoflurane. 1 ml/kg dosage of 300 mgI/ml iohexol was administered at a rate of 3 ml/s during GFR measurement. CT-GFR was determined with a single-slice dynamic acquisition and Patlak plot analysis. The individual and global GFR values were calculated to plasma clearance per body weight (ml/min/kg). Bodyweight ($mean{\pm}SD$) ranged from 2.0 to 5.7 kg ($3.31{\pm}1.13$ kg). Age ranged from 3 years to 13 years old ($7.14{\pm}3.30$). $Mean{\pm}SD$ creatinine ($0.53{\pm}0.34 $mg/dl), phosphorus ($4.1{\pm}1.2$ mg/dL), and albumin ($3.3{\pm}0.3$ mg/dL) concentrations and urine protein-to-creatinine ratios (all ratios were < 0.5) were within reference ranges. Abdominal ultrasonography revealed small-sized renal calculi, mineralization, or renal cyst at eight dogs. The global CT-GFR ranges shown in this study was 2.57 to 6.60 ml/min/kg. In this study, there was no trend toward weight-adjusted CT-GFR with increasing age. We found no relationships between age-related kidney dysfunction in fifteen dogs. Small-sized renal calculi or cysts did not affect renal function in this study. However, it is thought that a large sample size may have been required to document an age effect.

• 대한핵의학회:학술대회논문집
• /
• 2001.05a
• /
• pp.60-65
• /
• 2001

The positron emission tomography (PET) has been used for the evaluation of the characteristics of various tumors. The role of PET in oncology has been evolved from a pure research tool to a methodology of enormous clinical potential. The unique characteristics of PET imaging make sophisticated quantitation possible. Several quantitative methods, such as standardized uptake values (SUV), simplified quantitative method, Patlak graphical analysis, and Sokoloff's glucose metabolism measurement, have been used in the field of oncology. However, each quantitative method has limitations of its own. For example, the SUV has been used as a quantitative index of glucose metabolism for tumor classification and monitoring response to treatment, even though it depends on blood glucose level, body configuration of patient, and scanning time. The quantitative methods of PET are reviewed and strategy for implementing these methods are presented.

• The Korean Journal of Nuclear Medicine
• /
• v.32 no.4
• /
• pp.332-343
• /
• 1998

Purpose: The purpose of this study was to assess the diagnostic accuracy of various quantitation methods using F-18-fluorodeoxyglucose (FDG) in patients with malignant or benign lung lesion. Materials and Methods: 22 patients (13 malignant including 5 bronchoalverolar cell cancer; 9 benign lesions including 1 hamartoma and 8 active inflammation) were studied after overnight fasting. We performed dynamic PET imaging for 56 min after injection of 370 MBq (10 mCi) of FDG. Standardized uptake values normalized to patient's body weight and plasma glucose concentration (SUVglu) were calculated. The uptake rate constant of FDG and glucose metabolic rate were quantified using Patlak graphical analysis (Kpat and MRpat), three compartment-five parameter model (K5p, MR5p), and six parameter model taking into account heterogeneity of tumor tissue (K6p, MR6p). Areas under receiver operating characteristic curves (ROC) were calculated for each method. Results: There was no significant difference of rate constant or glucose metabolic rate measured by various quantitation methods between malignant and benign lesions. The area under ROC curve were 0.73 for SUVglu, 0.66 for Kpat, 0.77 for MRpat, 0.71 for K5p, 0.73 for MR5p, 0.70 for K6p, and 0.78 for MR6p. No significant difference of area under the ROC curve between these methods was observed except the area between Kpat vs. MRpat (p<0.05). Conclusion: Quantitative methods did not improve diagnostic accuracy in comparison with nonkinetic methods. However, the clinical utility of these methods needs to be evaluated further in patients with low pretest likelihood of active inflammation or bronchoalveolar cell carcinoma.