• The Korean Journal of Nuclear Medicine
• /
• v.29 no.4
• /
• pp.465-472
• /
• 1995

An accurate preoperative localization in patients with primary hyperparathyroidism is important for successful surgical intervention. There are many methods for the localization of the primary hyperparathyroidism such as ultrasonography, computerized tomography(CT), magnetic resonance imaging(MRI), angiography and $^{201}T1/^{99m}Tc$ subtraction scan. Among them $^{201}T1/^{99m}Tc$ subtraction scan is known as the most accurate tool for preoperative localization. Recently $^{99m}Tc$-Sestamibi has been used for parathyroid gland imaging. We experienced 19 primary hyperparathyroidisms accurately localized with $^{201}T1/^{99m}Tc$ subtraction imaging and $^{99m}Tc$-Sestamibi. The sensitivities of the $^{99m}Tc$-Sestanibi, $^{201}T1/^{99m}Tc$ subtraction imaging, CT and US were 100%(5/5), 89.5%(17/19) and 61.7(12/19) respectively. With the combination of $^{99m}Tc$-Sestamibi and $^{201}T1/^{99m}Tc$ subtraction imaging we could localize with 100% accuracy. Although the case number is small, this study suggests that the $^{99m}Tc$-Sestamibi parathyroid scan is very useful and easy to use for preoperative localization in primary hyperparathyroidism.

• Journal of Radiopharmaceuticals and Molecular Probes
• /
• v.3 no.1
• /
• pp.38-43
• /
• 2017

Tc-99m labeled sestamibi ($^{99m}Tc$-MIBI) is one of most widely used radiopharmaceuticals for myocardial SPECT imaging. Radiolabeling of $^{99m}Tc$-MIBI is recommended by heating in $100^{\circ}C$ water bath for 15 min. However, the water bath might be a source of contamination. Thus, if radiolabeling of $^{99m}Tc$-sestamibi can be performed at room temperature, then it would be more convenient to use in clinical application. In this study, we performed the radiolabeling of $^{99m}Tc$-MIBI in different temperature conditions or using different instruments to find out the efficient labeling condition. We studied the $^{99m}Tc$-MIBI labeling at room temperature or $100^{\circ}C$ heating block, and checked the labelling yields every 1 min for 10 min using radio-TLC with 2 different eluents-saline and acetone. From the experiment, we confirmed that the $^{99m}Tc$-MIBI can be labeled over 90% yield but not completed at room temperature. However, the $^{99m}Tc$-MIBI labeling was completed when it was performed in the $100^{\circ}C$ heating block. Finally, we proved that heating is essential for complete $^{99m}Tc$-MIBI labelling, furthermore using heating block is also possible instead of water bath.

• The Korean Journal of Nuclear Medicine
• /
• v.31 no.1
• /
• pp.57-66
• /
• 1997

We performed 1st day Tc-99m-sestamibi gated SPECT with dipyridamole/rest T1-201 SPECT and 2nd day 24 hour delay T1-201 SPECT/rest Tc-99m-sestamibi gated SPECT in 27 patients with coronary artery disease(24) or having chest pain(3). Stress and rest Tc-99m-sestamibi gated SPECT was acquired at 60min post-injection. A 4-point scoring system(0 to 3 for normal to absent tracer uptake) for 17 segments was used. Wall motion was scored on another 4 point scale(0 to 3 for normal to dyskinesia) in the 1st day post-stress gated and the 2nd day rest gated SPECT. Post-stress gated SPECT showed wall motion abnormality in 94 segments(20%). Fifty-five segments among these 94 showed the same wall motion between post-stress and rest gated SPECT: i.e. 1-1 23 segments, 2-2: 29 segments, 3-3: 3 segments. Remaining 39 segments(41.5%) showed different wall motion between post- stress and rest Tc-99m-sestamibi gated SPECT. Twenty one segments with wall motion abnormality had normal perfusion(rest : 15 segments, 24 hour delay: 6 segments) at either rest or 24 hour delay. Fifteen among these 21 segments showed persistent post-stress and the 2nd day rest wall motion abnormality(persistent stunning). However, in 6 segments with pro-longed (1 hour after stress) stunning, abnormal wall motion did improve in the 2nd day rest Tc-99m-sestamibi gated SPECT(transient prolonged stunning). These 6 segments had normal perfusion at rest(n=4) or at 24 hour delay(n=2). Post stress wall motions showed significantly higher scores in persistent stunning than in prolonged transient stunning(P value<0.05). It was concluded that we could find stunned myocardium with gated Tc-99m-sestamibi SPECT at either post-stress or rest and that some myocardial walls of post-stress 1 hour gated SPECT did not show truly rest wall motion. So, we should be cautious if we use post-stress Tc-99m-sestamibi wall motion to assess rest wall motion.

• The Korean Journal of Nuclear Medicine
• /
• v.33 no.4
• /
• pp.368-380
• /
• 1999

Purpose: The purpose of this study was to evaluate and compare the scintigraphic findings and diagnostic accuracy of double-phase Tc-99m sestamibi scan in primary and secondary hyperparathyroidism (HPT). Materials and Methods: We retrospectively reviewed 16 cases of primary (18 lesions) and 11 cases of secondary HPT (44 lesions) who underwent Tc-99m-sestamibi scan before the surgical intervention. Scan was performed using LEM camera (Siemens, Germany) after the injection of 740MBq of Tc-99m sestamibi. Routine image consisted of baseline and 3-hour delayed images and each image was obtained using both parallel and pine hole collimator. The study population was 27 patients (male/female=5/22, age: $49.1{\pm}10.8$). Results: Eighteen lesions of primary HPT consisted of 13 adenomas and S hyperplasias, while all lesions of secondary HPT were hyperplasias. Among the case of primary HPT, we could detect all the lesions of 13 adenomas but only 2 lesions of 5 hyperplasias (40%) could be detected by double phase scintigraphy. Three cases of primary lesion showed decreased uptake in delayed images compared with baseline. The sensitivity, specificity, positive predictive value and accuracy of primary and secondary HPT were 58.8% (10/17), 83.3% (10/12), 83.3% (10/12), 75.9% (22/29), and 37.5% (15/40), 50% (2/4), 88.2% (15/17), 38.6% (17/44), respectively. Overall sensitivity, specificity, positive predictive value and accuracy were 43.9% (25/57), 75% (12/16), 86.2% (25/29), and 53.4% (39/73). There were no statistical difference between the weight of primary and secondary HPT lesion (p>0.05). Conclusion: Tc-99m sestamibi scan is fairly good modality to detect parathyroid lesion in patient with primary HPT before the surgical intervention. However, since some of cases may reveal decreased uptake in delayed image, a careful attention to the findings of baseline images may be helpful. Still the low accuracy of sestamibi scan in diagnosis of secondary HPT prohibits routine use of it for this disease.

• Nuclear Medicine and Molecular Imaging
• /
• v.42 no.5
• /
• pp.354-361
• /
• 2008

Purpose: N-13 ammonia uptake and retention in the myocardium is related to perfusion and metabolism. There are several potential advantages of N-13 ammonia positron emission tomography (PET) to detect myocardial ischemia, such as higher spatial resolution, greater counting efficiencies, and robust attenuation correction. But there are few reports comparing Tc-99m myocardial perfusion single photon emission tomography (MPS) and N-13 ammonia PET. We thus compared adenosine stress N-13 ammonia PET/CT and Tc-99m sestamibi MPS in patients with suspected coronary artery stenosis. Materials and Methods: Seventeen patients (male 13 : $63{\pm}11$ years old) underwent adenosine stress N-13 ammonia PET/CT (Discovery ST, GE), Tc-99m sestamibi MPS (dual head gamma camera, Hawkeye, GE) and coronary angiography within 1 week. N-13 ammonia PET/CT and Tc-99m sestamibi MPS images were assessed with a 20-segment model by visual interpretation and quantitative analysis using automatic quantitative software (Myovation, GE). Results: Both sensitivities and specificities of detecting an individual coronary artery stenosis were higher for N-13 ammonia PET/CT than Tc-99m sestamibi MPS (PET/CT: 91%/89% vs MPS: 65%/82%). N-13 ammonia PET/CT showed reversibility in 52% of segments that were considered non-reversibile by Tc-99m sestamibi MPS. In the 110 myocardial segments supplied by the stenotic coronary artery, N-13 ammonia PET/CT showed higher count densities than Tc-99m MPS on rest study (p < 0.01), and the difference of count density between the stress and the rest studies was also larger on N-13 ammonia PET/CT. Conclusion: Adenosine stress N-13 ammonia PET/CT had higher diagnostic sensitivity and specificity, more reversibility of perfusion defects and greater stress/rest uptake differences than Tc-99m sestamibi MPS. Accordingly, N-13 ammonia PET/CT might offer better assessment of myocardial ischemia and viability.

• Proceedings of the Korean Nuclear Society Conference
• /
• 1999.05a
• /
• pp.381-381
• /
• 1999

• Nuclear Medicine and Molecular Imaging
• /
• v.41 no.3
• /
• pp.209-217
• /
• 2007

Purpose: Multidrug resistance (MDR) of the cancer cells related to mdr1 gene expression can be effectively treated by selective short hairpin RNA for mdr1 gene (shMDR). Sodium/iodide symporter (NIS) gene is well known to have both reporter and therapeutic gene characteristics. We have co-transfected both shMDR and NIS gene into colon cancer cells (HCT15 cell) expressing MDR and Tc-99m sestamibi and I-125 uptake were measured. In addition, cytotoxic effects of doxorubicin and I-131 therapy were also assessed after transfection. Material and Methods: At first, shMDR was transfected with liposome reagent into human embryonic kidney cells (HEK293) and HCT cells. shMDR transfection was confirmed by RT-PCR and western blot analysis. Adenovirus expressing NIS (Ad-NIS) gene and shMDR (Ad-shMDR) were co-transfected with Ad-NIS into HCT15 cells. Forty-eight hours after infection, inhibition of P-gycoprotein (Pgp) function by shMDR was analyzed by a change of Tc-99m sestamibi uptake and doxorubicin cytotoxicity, and functional activity of induced NIS gene expression was assessed with I-125 uptake assay. Results: In HEK293 cells transfected with shMDR, mdr1 mRNA and Pgp protein expressions were down regulated. HCT15 cells infected with 20 MOI of Ad-NIS was higher NIS protein expression than control cells. After transfection of 300 MOI of Ad-shMDR either with or without 10 MOI of Ad-NIS, uptake of Tc-99m sestamibi increased up to 1.5-fold than control cells. HCT15 cells infected with 10 MOI of Ad-NIS showed approximately 25-fold higher I-125 uptake than control cells. Cotransfection of Ad-shMDR and Ad-NIS resulted in enhanced cytotoxic by doxorubicin in HCT15 cells. I-131 treatment on HCT15 cells infected with 20 MOI of Ad-NIS revealed increased cytotoxic effect. Conclusion: Suppression of mdr1 gene expression, retention of Tc-99m sestamibi, enhanced doxorubicin cytotoxicity and increases in I-125 uptake were achieved in MDR expressing cancer cell by co-transfection of shMDR and NIS gene. Dual therapy with doxorubicin and radioiodine after cotransfection shMDR and NIS gene can be used to overcome MDR.

• Journal of The Korean Radiological Technologist Association
• /
• v.24 no.2
• /
• pp.145-151
• /
• 1998

• The Korean Journal of Nuclear Medicine
• /
• v.30 no.1
• /
• pp.104-111
• /
• 1996

We did Tc-99m sestamibi myocardial perfusion SPECT in 36 patients with acute myocardial infarction when they arrived at the emergency room. And we compared myocardial perfusion images with ECG findings. Then we obtained the follows. The myocardial infarction by the obstruction of left coronary descending artery and right coronary artery showed a good concordance in the diagnosis and infarction site between myocardial perfusion images and ECG findings. The 7 patients with myocardial infarction by a left circumflex coronary artery showed a perfusion defect in the lateral wall in myocardial perfusion SPECT images. But 4 patients of them showed ST segment elevation, 2 patients showed ST depression and 1 patient showed normal ECG findings. The diagnostic sensitivity of Tc-99m sestamibi myocardial perfusion SPECT was 100% by a qualified analysis. The perfusion defect site in the myocardial perfusion SPECT were corresponded with the infarct related coronary artery in 31 patients which was diagnosed by coronary angiograpy. The size of perfusion defect in the po1ar map was $31{\pm}18%(M{\pm}SD)$, in the myocardial infarction with left anterior descending coronary arery obstruction, $31{\pm}13% (M{\pm}SD)$ in the myocardial infarction with right coronary artery obstruction and $25{\pm}5.9%(M{\pm}SD)$ in the myocardial infarction with left circumflex coronary artery obstruction. We concluded that emergency myocardial perfusion SPECT images are useful in the diagnose of myocardial infarction and it's very useful when we are difficult to diagnose with ECG like as lateral wall infarction or left bundle branch block.

• 대한핵의학회:학술대회논문집
• /
• 2002.11a
• /
• pp.29.1-29.1
• /
• 2002