핵의학적 세포증식 영상

여정석 대한핵의학회 2004 핵의학 분자영상 Vol.38 No.2

Tumor cell proliferation is considered to be a useful prognostic indicator of tumor aggressiveness and tumor response to therapy, but in vitro measurement of individual proliferation is complex and tedious work. PET imaging provides a noninvasive approach to measure tumor growth rate in situ. Early approaches have used ^(18)F-FDG or methionine to monitor proliferation status. These 2 tracers detect changes in glucose and amino acid metabolism, respectively, and therefore provide only an indirect measure of proliferation status. More recent studies have focused on DNA synthesis itself as a marker of cell proliferation. Cell lines and tissues with a high proliferation rate require high rates of DNA synthesis. [^(11)C]Thymidine was the first radiotracer for noninvasive imaging of tumor proliferation. The short half-life of ^(11)C and rapid metabolism of [^(11)C]thymidine in vivo make the radiotracer less suitable for routine use. Halogenated thymidine analogs such as 5-iodo-2-deoxyuridine (IUdR) can be successfully used as cell proliferation markers for in vitro studies because these compounds are rapidly incorporated into newly synthesized DNA. IUdR has been evaluated as a potential in vivo tracer in nuclear medicine, but the image quality and the calculation of proliferation rates are impaired by its rapid in vivo degradation. Hence, the thymidine analog 3'-deoxy-3'-^(18)F-fluorothymidine (FLT) was recently introduced as a stable proliferation marker with a suitable nuclide half-life and stable in vivo. [^(18)F]FLT is phosphorylated to 3-fluorothymidine monophosphate by thymidine kinase 1 and reflects thymidine kinase 1 activity in proliferating cell. [^(18)F]FLT PET is feasible in clincal use and well correlates with cellular proliferation. Choline is a precursor for the biosynthesis of phospholipids (in particular, phosphatidylcholine), which is the essential component of all eukaryotic cell membranes and [^(11)C]choline, which is a new marker for cellular proliferation. (Korean J Nucl Med 38(2):198-204, 2004)

Tc-99m-MIBI 심근 SPECT 의 분절 육안 분석시 판독자간의 일치도

여정석,이동수,이경한,김종호,손경수,조성욱,곽철은,정준기,이명철,서정돈,고창순 ( Jeong Seok Yeo,Dong Soo Lee,Kyung Han Lee,Jong Ho Kim,Kyung Soo Shon,Sung Wook Cho,Cheol Eun Kwark,June Key Chung,Myung Chul Lee,Jeong Don Seo,Chang Soon 대한핵의학회 1994 핵의학 분자영상 Vol.28 No.3

The accuracy of dipyridamole stress/rest 99mTc-MIBI myocardial imaging for detection of ischemia depends on reproducible image interpretation. To evaluate the reproducibility of visual assessment, agreement in interpretation among two independent obervers, blinded to clinieal data, was evaluated in SPECT images of 131 patients (94 males, 38 fe- males, mean age 58+7 yr) with suspected coronary artery disease who underwent both dipyridamole st,ress/rest 99mTc-MJBI myocardial SPECT and coronary angiography, The left ventricle was divided into twenty-nine segments in stress and rest SPECT images and each segment was visually graded according to a five point scale (segmental score : O=normal, 1 =equivocal, 2=mild decrease, 3=severe decrease and 4=absent uptake). Overall concordance of segmental scoring between the two observers was 80%. The Pear- sons correlat.ion coefficient (r) of the segmental scores for stress and rest images were 0.67 and 0.65, respectively, while the difference in score between the two images showed a correlat,ion of 0.45 (all p<0,001). Agreement between two observers in final SPECT diagnosis as absence or presence of disease was 93%. The degree of agr eement in segmental scoring showed no difference between patients with or without agreement as to the presence of disease. Therefore it appeared that cases with inconcordant diagnosis between the 2 observers were mainly due to a difference in individual threshold for interpretating the significance of a particular decreased uptake area rather (han to a difference in perceiving the degree of the hypoactivity, Thus, establishment of individual optimum thresholds in visual interpretation of myocardial SPECT may be helpful to improve reproducibility and acruracy of scan ditagnosis.

갑상선암에서 PET 의 역할

여정석(Jeong Seok Yeo) 대한핵의학회 2002 핵의학 분자영상 Vol.36 No.3

The role of PET in the diagnosis and management of thyroid cancer is discussed. The major role of F-18 FDG PET is in patients with discordant negative I-131 scan and a positive serum thyroglobulin values. F-18 FDG PET scan localized metastatic sites in I-131 scan-negative thyroid carcinoma patients with high accuracy. F-18 PET is also valuable in medullary thyroid cancer with high calcitonin level. Focal thyroid uptake in patients with non-thyroidal diseas has high likelihood of thyroid cancer. (Korean J Nucl Med 2002;36;147-54)

제43차 대한핵의학회 추계학술대회 : 포스터 ; 무증상 환자에서 암 선별 검사로서의 18F-Fluorodeoxyglucose Positron Emission Tomography의 유용성

홍일기,여정석,양유정,류진숙,문대혁 대한핵의학회 2004 핵의학 분자영상 Vol.38 No.5

저온시동시의 유해배기가스 저감대책에관한 실험적연구

박경석,여정석 경희대학교 환경연구소 1994 環境硏究 論文集 Vol.5 No.-

It is a important facter to reduce automobile emissions. This paper deals with the estimation of catalyst characteristics for the automobile emission control by the electrically-heated catalyst converter. First of all, the after treatment method is required for LEV(Low Emissoin Vehicle) after FTP-75 mode limitation, the after treatment method is divided into two ways. Development of catalysis and reduction of catalyst activity time. Electrically heated monoliths have been designed and tested that are able to reach catalystic light-off temperature in less than 30 second using a conventional 12 volt electrical system. Gasoline vehicle emission data are presented that show substantial improvements in cold start HC and CO emissions by using resistance heating.

Tc-99m 표지 항과립구항체 면역신티그라피를 이용한 골수염의 진단

강원준,정준기,여정석,홍미경,정재민,이동수,이상훈,최인호,이명철 ( Won Jun Kang,June Key Chung,Jeong Seok Yeo,Mee Kyoung Hong,Jae Min Jeong,Dong Soo Lee,Sang Hoon Lee,In Ho Choi,Myung Chul Lee ) 대한핵의학회 1998 핵의학 분자영상 Vol.32 No.4

Purpose: The purpose of this study was to evaluate the diagnostic accuracy of Tc-99m labeled antigranulocyte antibody immunoscintigrapy in the diagnosis of osteomyelitis and compare with the results of triphasic bone scan. Materials and Methods: The study popula- tion was 39 patients (22 male, 17 female) who had uncertain diagnoses of osteomyelitis. Fifteen patients had history of orthopedic surgery, and 5 had previous fracture. One milligram of monoclonal antibody against NCA-95 was labeled with 370 MBq of Tc-99m, injected intravenously, and 4 hour images were obtained. Triphasic bone scan images were obtained in 30 p;tients. The final diagnosis was confirmed by bacteriologic culture, biopsy or long term clinical follow up. Results: Twenty one patients were confirmed to have osteomyelitis (1 acute, 20 chronic). Eighteen patients were without osteomyelitis. Antigranulocyte antibody immunoscintigraphy had a sensitivity of 71% (15/21), and a specificity of 89% (16/18), while the sensitivity and specificity of triphasic bone scan was 93% (13/14) and 38% (6/16), respectively. Antigranulocyte antibody scan showed higher specificity of 100% (11/11) in comparison with 33% (3/9) of triphasic bone scan in patients with history of orthopedic surgery or fracture. Conclusion: Antigranulocyte antibody immunoscintigraphy is more specific than that of triphasic bone scan and may be helpful in patients with history of surgery or fracture. However, sensitivity is lower than triphasic bone scan in the detection of chronic osteomyelitis. (Korean J Nucl Med 1998;32:344-53)

국소대발 및 정이성 유방암 진단의 FDG PET과 99mTc-MIBI SPECT의 비교

이동수,이명철,정준기,김성장,여정석 대한핵의학회 1999 핵의학 분자영상 Vol.33 No.5

고식적 검사로 간외 전이를 진단하지 못한 원발성 간암 환자에서 간이식 전에 시행한 전신 FDG-PET의 역할

이원우,류진숙,양유정,김재승,여정석,문대혁,이승규 대한핵의학회 2002 핵의학 분자영상 Vol.36 No.6

목적: 원발성 간암의 치료를 위해 간이식이 시행되고 있으나, 8-54%의 환자에서는 이식 후 원격 전이로 인한 재발이 보고 되고 있다. 이 연구는 간이식 예정인 원발성 간암 환자들에서 고식적인 검사로 진단하지 못한 간의 전이 진단에 있어서 FDG-PET의 유용성을 평가하고자 시행되었다. 대상 및 방법: 2001년 8월 이후 본원에서 간이식을 계획하고 전신 FDG-PET을 시행한 환자 중, FDG-PET 검사 이전에 복부 초음파와 CT, 흉부 x선 검사와 CT, 골스캔 등의 고식적인 검사를 시행하여 전이의 증거가 없거나(n=22), 애매한 이상 소견이 있었던(n=4) 원발성 간암 환자 26명(남:여=23:3), 평균 나이 55.7세)을 조사하였다. FDG-PET에서 양성을 보인 결과는 조직 검사나 임상적인 추적 검사로 전이 여부를 확인하였다. 결과: 고식적 검사에서 애매한 이상 소견이 있었던 환자 4명 중 3명의 6개 병변이 FDG-PET에서 국소 대사 항진을 보였고, 전이로 확인되어 간이식을 시행하지 않았다. 이 중 5 병변들은 의심되지 않았던 부위에서 새로 발견된 것이었다. 다른 1명은 PET에서 음성 소견으로 간이식을 시행하였다. 고식적인 검사에서 전이를 의심할 만한 소견이 없었던 22명 중에서는 5명의 환자에서 7개의 간의 국소 대사항진 병변들이 FDG-PET에서 발견되었는데, 이들 줄 1명은 2 개의 전이 병변이 확인되어 간이식을 시행하지 않았다. 다른 4명의 환자들에서 보인 5개의 국소 대사항진 병변들은 양성병변으로 확인되었고 이 중 3명은 간이식을 시행하였다. 요약하면, FDG-PET으로 4명의 환자에서 고식적인 검사로 찾지 못하던 전이 병변을 찾아 불필요한 간이식을 피할 수 있었다. 모두 17명에서 간이식이 시행되었다. 간의 조직 검사 소견과 비교하였을 때 생존 원발성 간암을 진단하는 FDG-PET의 민감도는 55.6% (5/9)이었고, 특이도는 87.5% (7/8)이었다. 결론: FDG-PET 전신 스캔은 간이식 예정인 원발성 간암 환자들에서 이전에 시행한 고식적인 검사들로 진단하지 못한 전이 병소들을 추가로 진단하여 불필요한 간이식 수술을 줄이는데 기여할 수 있었다. Purpose: Liver transplantation (LT), one of the therapeutic options of primary liver cancer has been suffering from recurrence caused by metastasis in 8-54% of patients. This study was performed to investigate whether FDG-PET is useful for detecting hidden metastasis in LT candidates. Materials and Methods: Twenty-six patients (male:female=23:3, mean age 55.7 year) underwent FDG-PET. Their previous conventional diagnostic studies (CDS) like a abdomen US and CT, chest x-ray and CT, and bone scan were negative (n=22) or equivocal (n=4) for metastasis. Positive FDG-PET findings were confirmed by biopsy or clinical follow-up. Results: Among 4 patients with equivocal metastatic lesions on CDS, 3 had 6 hypermetabolic lesions on FDG-PET, which were confirmed as metastasis and subsequently LTs were cancelled. Of these, 5 lesions were initially negative on CDS. Remained 1 patient underwent LT with a negative FDG-PET result. Among 22 patients without metastasis on CDS, 5 had 7 hypermetabolic lesions on FDG-PET. One of these patients proved to have 2 metastatic lesions, and LT was cancelled. The other 4patients had 5 hypermetabolic lesions on FDG-PET, which were confirmed as benign lesions, and 3 patients of them underwent LT. In summary, FDG-PET was useful in avoiding 4 unwarranted LT by detecting unsuspected metastatic lesions on CDS. A total of 17 patients underwent LT. In comparison with pathology, the sensitivity and specificity of FDG-PET for detecting viable primary liver cancer were 55.6% (5/9) and 87.5% (7/8), respectively. Conclusion: FDG-PET can detect additional hidden metastasis and contribute to reducing unwarranted LT in the patients with primary liver cancer. (Korean J Nucl Med 2002;36;368-80)

방사성옥소(I-131) 갑상선 치료 환자에서 새로운 격리 기준

이동수,정준기,김석기,강건욱,여정석,이명철 대한핵의학회 1999 핵의학 분자영상 Vol.33 No.5

Altered Glucose Metabolism in Juvenile Myoclonic Epilepsy: a PET Study with Statistical Parametric Mapping

임기천,김지현,강중구,김재승,여정석,이상암,문대혁 대한핵의학회 2004 핵의학 분자영상 Vol.38 No.5