1.Scintillation Proximity Assay.
Korean Journal of Nuclear Medicine 1999;33(6):461-465
Scintillation proximity assay (SPA) is a unique type of radioimmunoassay and makes it possible to use radioisotopes for monitoring binding reactions continuously without separation procedure. Microbeads containing a fluorophor are covalently linked to antibody or receptor. When a radiolabeled antigen or ligand is added it binds to the beads and the emitted short range electrons, excite the fluorophor in the beads. The light emitted can be measured in a scintillation counter. 3H or 125I has been used for SPA. The sensitivities achieved with SPA are comparable to the sensitivities of other procedures. SPA is applicable to immunology, receptor binding, monitoring interactions of biomolecules and study for the kinetics of interaction between receptors and ligands.
Allergy and Immunology
;
Kinetics
;
Ligands
;
Microspheres
;
Radioimmunoassay
;
Radioisotopes
;
Scintillation Counting
2.Radiation Synovectomy: when, which disease, and which joint.
Korean Journal of Nuclear Medicine 1999;33(2):196-199
Radiation synovetomy with various radiopharmaceuticals has been used to alleviate pain and swelling of rheumatoid arthritis and related joint diseases for more than 40 years. It is an attractive alternative to the surgical synovectomy for the management of the various joint diseases. Recently, the development of new radiopharmaceuticals labeled with 90Y, 32P, 186Re, 188Re, 153Sm, 165DY and 166Ho, for the effective management of synovial inflammation and related arthritic problems are gaining attention. In this article the general concepts and the clinical application of radiation synovectomy are reviewed.
Arthritis
;
Arthritis, Rheumatoid
;
Inflammation
;
Joint Diseases
;
Joints*
;
Radiopharmaceuticals
3.Clinical Application of PET in Abdominal Cancers.
Korean Journal of Nuclear Medicine 2002;36(1):39-45
No abstract available.
4.Clinical Application of PET in Abdominal Cancers.
Korean Journal of Nuclear Medicine 2002;36(1):39-45
No abstract available.
5.Synthesis of Substrates for Gene Therapy Monitoring of HSV1-TK System.
Soon Hyuk AHN ; Chang Woon CHOI ; Sang Moo LIM ; Ok Doo AWH ; Tae Hyun CHOI
Korean Journal of Nuclear Medicine 2002;36(2):102-109
No abstract available.
Genetic Therapy*
6.Nuclear Medicine in Oncology.
Journal of the Korean Medical Association 2003;46(3):186-195
Nuclear oncolgy is important in the diagnosis, staging, and long-term surveillance of a number of cancers. Over the past 10 years there has been an explosion of new radioisotopic tracers aimed at detecting, staging and eventually treating tumors. Clinicians and oncologists can now use specific radiolabeled metabolic tracers, monoclonal antibodies, and molecular probes based on the sequencing of the human genome. The current applications of positron emission tomography (PET) in oncology have included characterizing tumor lesions, differentiating recurrent disease from treatment effects, staging tumors, evaluating the extent of disease, and monitoring therapy. The future developments in medicine may use the unique capabilities of PET not only in diagnostic imaging but also in molecular medicine and genetics. Radioimmunoscintigraphy is a technique which uses radiolabeled antibodies to visualize tumors, taking advantage of antigens preferentially expressed by malignant tissue. However, the implementation of radiolabeled antibodies as "magic bullets" for detection and treatment of diseases such as cancer has required addressing several shortcomings of murine monoclonal antibodies. Genetic engineering provides a powerful approach for redesigning antibodies for use in oncologic applications in vivo. Recently, noninvasive molecular imaging has been developed. Most current molecular imaging strategies are "indirect" and involve the coupling of a "reporter gene" with a complementary "reporter probe". Imaging the level of probe accumulation provides indirect information related to the level of reporter gene expression. In this article, the author discuss the current status of PET, radioimmunoscintigraphy, gene imaging and receptor imaging with a brief review on nuclear oncology.
Antibodies
;
Antibodies, Monoclonal
;
Diagnosis
;
Diagnostic Imaging
;
Explosions
;
Genes, Reporter
;
Genetic Engineering
;
Genetics
;
Genome, Human
;
Humans
;
Molecular Imaging
;
Molecular Medicine
;
Molecular Probes
;
Nuclear Medicine*
;
Positron-Emission Tomography
;
Radioimmunodetection
7.Improved Activity Estimation using Combined Scatter and Attenuation Correction in SPECT.
Jeong Rim LEE ; Chang Woon CHOI ; Sang Moo LIM ; Seong Wun HONG
Korean Journal of Nuclear Medicine 1998;32(4):382-390
PURPOSE: The pvrpose of this study was to evaluate the accuracy of radioactivity quantitation in Tc-99m SPECT by using combined scatter and attenuation correction. MATERIALS AND METHODS: A cylindrical phantom which simulates tumors (T) and normal tissue (B) was filled with varying activity ratios of Tc-99m. We acquired emission scans of the phantom using a three-headed SPECT system (Trionix, Inc.) witb two energy windows (photopeak window: 126 154 keV and scatter window: 101 123 keV). We performed the scatter correction with dual-energy window subtraction method (k=0.4) and Chang attenuation correction. Three sets of SPECT images were reconstructed using combined scatter and attenuation correction (SC+AC', attenuation correction (AC) and without any correction (NONE). We compared T/B ratio, irnage contrast [(T-B)/(T+B)) and absolute radioactivity with true values. RESULTS: SC+AC images had the highest mean values of T/B ratios. Image contrast was 0.92 in SC+AC, which was close to the true value of 1, and higher than AC (0.77) or NONE (0.80). Errors of true activity by SPECT images ranged from 1 to 11% for SC+AC, 22-47% for AC, and 2 16% for NONE in a phantom which was located 2.4cm from the phantom surface. In a phantom located 10,0cm from the surface, SC+AC underestimated by ?4%, NON.E 40%. However, AC overestimated by 10%. CONCLUSION: We conclude that accurate SPECT activity quantitation of Tc-99m distribution can be achieved by dual window scatter correc.tion combined with attenuation correction.
Radioactivity
;
Tomography, Emission-Computed, Single-Photon*
8.Absent perfusion and nonvisualization by renal scintigraphy in a case of transplant kidney.
Sang Kyun BAE ; Hyung In YANG ; Chang Woon CHOI ; Dong Soo LEE ; June Key CHUNG ; Myung Chul LEE ; Chang Soon KOH
Korean Journal of Nuclear Medicine 1992;26(2):400-410
No abstract available.
Kidney*
;
Perfusion*
;
Radionuclide Imaging*
9.Regional hyperperfusion in early stage of herpes simplex encephalitis demonstrated by 99mTc-HMPAO brain SPECT.
Sang Eun KIM ; Chang Woon CHOI ; Dong Soo LEE ; June Key CHUNG ; Myung Chul LEE ; Chang Soon KOH
Korean Journal of Nuclear Medicine 1991;25(1):129-130
No abstract available.
Brain*
;
Encephalitis, Herpes Simplex*
;
Herpes Simplex*
;
Technetium Tc 99m Exametazime*
;
Tomography, Emission-Computed, Single-Photon*
10.Regional hyperperfusion in early stage of herpes simplex encephalitis demonstrated by 99mTc-HMPAO brain SPECT.
Sang Eun KIM ; Chang Woon CHOI ; Dong Soo LEE ; June Key CHUNG ; Myung Chul LEE ; Chang Soon KOH
Korean Journal of Nuclear Medicine 1991;25(1):129-130
No abstract available.
Brain*
;
Encephalitis, Herpes Simplex*
;
Herpes Simplex*
;
Technetium Tc 99m Exametazime*
;
Tomography, Emission-Computed, Single-Photon*