• Nuclear Medicine and Molecular Imaging
• /
• v.43 no.2
• /
• pp.112-119
• /
• 2009

Purpose: This study was performed to investigate the clinical significance of reverse redistribution(RR) phenomenon detected on delayed Tc-99m tetrofosmin myocardial single photon emission computed tomography(SPEG) in patients with acute myocardial infarction after revascularization. Materials and Methods: A Tc-99m tetrofrosmin myocardial SPECT was performed in 67 consecutive patients after revascularization for acute myocardial infarction. Myocardial SPECT imaging was performed for early imaging at 40 min and for delayed imaging at 180 min after reinjection at myocardial stress. Regional myocardial uptakes were scored by 4-point scoring in the left ventricular wall divided into 17 segments. Reverse redistribution was defined as an increase of more than 2 point in the activity score on the delayed image. Follow-up myocardial SPECT and coronary angiography(CAG) were performed 9 months later. Results: On myocardial SPECT performed following revascularization, RR was observed in 100 of all 319 segments(31%) and in 43 patients(64%). The abnormalities of perfusion and regional wall motion were more severe in the patients with RR compared to those without RR(p<0.05). On follow-up myocardial SPECT, the myocardial perfusion, regional wall motion, and myocardial thickness were significantly improved in the patients with RR(p<0.05) however, these changes were not significant in those without RR. There was no significant difference between the patients with RR and those without RR in the occurrence of restenosis on CAG. Conclusions: In patients with acute myocardial infarction, the regions showing the RR phenomenon on delayed Tc-99m tetrofosmin SPECT may reflect viable myocardium and indicate recovery of salvaged myocardium.

• The Korean Journal of Nuclear Medicine
• /
• v.23 no.1
• /
• pp.13-18
• /
• 1989

To evaluate diagnostic accuracy of $^{99m}Tc-pyrophosphate$ (PYP) myocardial scan, we analysed 160 $^{99m}Tc-PYP$ scans (acute transmural myocardial infarction 87 cases, acute subendocardial infarction; 20 cases, unstable angina pectoris; 7 cases, other disease; 46 cases). These scans were requested by the physician in Seoul National University Hospital from Sep. 1982 to Oct. 1987. And the diagnosis was confirmed by clinical course and laboratory examinations. 1) The diagnostic sensitivity of $^{99m}Tc-PYP$ scan in acute transmural myocardial infarction was 91.2% (62/68) if scintigraphy was performed within 7 days after infarction, 57.1% (8/14) between 8th and 14th day, 20% (1/5) and after 15 days. 2) The diagnostic sensitivity of $^{99m}Tc-PYP$ scan in acute subendocardial infarction was 75% (12/16) if scintigraphy was performed within 7 days after infarction and 0% after 8 days. 3) The diagnostic specificity of $^{99m}Tc-PYP$ scan in acute myocardial infarction was 94.3% (5/53). Among 5 cases of false positive scans, 1 case was unstable angina pectoris, 2 cases were old myocardial infarction with left ventricular aneurysm, 1 case was old myocardial infarction and the remaining 1 case was cardiomyopathy.

• The Korean Journal of Nuclear Medicine
• /
• v.19 no.1
• /
• pp.137-143
• /
• 1985

Using chelating agents such as Nitrilotriaceticacid(NTA), ticacid(DTPA) and Ethylenediaminenitrilotetraceticacid(EDTA), with TC-99m were determined in vitro and in vivo. Methods.of separation and determination of TC-99m-liposomes added chelating agents were practiced by thin layer chromatogram scan and gel filtration. Biodistributions of Tc-99m-liposomes in normal and sarcoma 180 cells bearing mice were observed. The results were as follows: 1) Maximum amount of $Sn^{+2}$ to reduction from pertechnetium$(10\sim20{\mu}ci)$ by adding 0, 1, 10 and $100{\mu}g$ of $SnCl_2$ in 0.2 ml of oxygen free water was $10{\mu}g$. 2) The large amounts of $SnCl_2$ were not changed but the small amounts of $SnCl_2$ were much changed by labeling with TC-99m to add chelating agents. EDTA in small amounts of $SnCl_2$ were reduced more strongly than DTPA or NTA. Using a hydrophilic chelate, DTPA, the uptake of liposomes could not accumulated in liver and spleen by a lipophilic chelate NTA were significant in vivo. 3) Uptake by tumor was achived 1.14% of injected dose per gram tissue and tumor to organ ratios were measured in low with TC-99m-NTA-liposomes(+).

• The Korean Journal of Nuclear Medicine
• /
• v.35 no.4
• /
• pp.291-292
• /
• 2001

We report a case of malignant pericardial effusion originated from adenocarcinoma of the lung incidentally diagnosed by bone scintigraphy, prior to echocardiographic detection. A 76 year-old man with adenocarcinoma of the lung underwent Tc-99m MDP bone scintigraphy to evaluate skeletal metastasis. Anterior images of the chest of the bone scintigraphy unexpectedly showed diffuse increased activity in the region of the heart surrounded by an oval-shaped band of increased activity corresponding to the periphery of the cardiac silhouette (Fig. 1). There was no evidence of bony metastasis. Pericardial effusion was confirmed by echocardiography (Fig. 2) and malignant cells were revealed by subsequent microscopic examination of the pericardial fluid. Bone scintigraphy using Tc-99m phosphate compounds is commonly used to detect bony metastasis in cancer patients. Tc-99m phosphate compounds occasionally accumulate in extra-osseous sites, including $pleural^{1,2)},\;pericardial^{3,4)},\;and\;ascitic\;fluids^{5,6)}$. It has been reported that their accumulation in serous effusions should strongly suggest $malignancy^{1-6)}$. The exact mechanism for accumulation of Tc-99m phosphate compounds in serous effusions is unclear. Several investigators have proposed that the radiopharmaceuticals exuded directly from peripheral vessels to the serous cavity due to increased vascularity and vascular permeability, and bleeding by disruption of blood vessels due to cancerous $infiltration^{5,6)}$.

• The Korean Journal of Nuclear Medicine
• /
• v.29 no.4
• /
• pp.460-464
• /
• 1995

[ $^{201}T1/^{99m}Tc$ ] pertechnetate subtraction scintigraphy of the parathyroid gland was performed in a study of 8 patients with clinical and biochemical evidence of hyperparathyroidism for diagnosis and Localization of the lesion prior to sugery. 6 cases of parathyroid adenomas were accurately localized and 2 cases of diffuse hyperplasia associated with chronic renal failure(CRF) and multiple endocrine neoplasia (MEN) type I. $^{201}T1/^{99m}Tc$ pertechnetate scan was useful for patients with hyperparathyroidism, especially in definite localization preoperatively.

• The Korean Journal of Nuclear Medicine
• /
• v.34 no.5
• /
• pp.436-437
• /
• 2000

A 63-year-old male who had subtotal gastrectomy for early gastric cancer three months ago underwent Tc-99m bone scintigraphy for the evaluation of skeletal metastases. He had no symptoms such as fever, tenderness, or wound discharge. On physical examination, the surgical scat along the midline of the upper abdomen had keloid formation and there was no radiographic evidence of calcification. Bone scintigraphy (Fig. 1A & 1B) demonstrated all unusual linear increased uptake along the midline of the upper abdomen that corresponded to the,skin incision for subtotal gastrectomy. Usually, an incisional scar will not be visualized in Tc-99m methylene diphosphate (MDP) scintigraphy beyond two weeks after surgery.$^{1)}$ Upon reviewing the literature, there were only a few reports where localization of Tc-99m MDP in surgical scars were found two months after surgery.$^{2)}$ It was also reported that a few cases with Tc-99m MDP uptake in the keloid scar developed after surgery. Although there are several potential mechanisms that may explain the uptake of Tc-99m MDP in scar tissue, the primary mechanism in older scars is suggested to be a result of pathological calcification.$^{2)}$ Siddiqui et al$^{3)}$ suggested it could be due to microscopic calcification in small resolving hematomas. However, the primary mechanism in keloid scar is not well-known. We should obtain oblique or lateral views to differentiate the uptake in healing surgical scars from the artifactual uptake.

• Childhood Kidney Diseases
• /
• v.7 no.2
• /
• pp.239-244
• /
• 2003

$^{99m}Tc-MAG3$ Scintigraphic Scan is sensitive at depicting focal parenchymal abnormalities and can be used for the measurement of overall renal function. We experienced a 12-year-old girl presenting with fever and flank pain. On the ultrasonogram and post-voiding delayed image of $^{99m}Tc-MAG3$ scintigraphic scan, severe right cortical atrophy and hydronephrosis with vesicoureteral reflux were detected. We could demonstrate the reflux nephropathy by these two diagnostic work-up without conventional voiding cystourethrography.

• The Korean Journal of Nuclear Medicine
• /
• v.29 no.1
• /
• pp.84-91
• /
• 1995

Many clinical and laboratory tests have been employed to evaluate disease activity in rheumatioid arthritis. $^{99m}Tc$-labelled polyclonal IgG(HIG) has been demonstrated to accumulate in focal sites of infection or inflammation in both animals and human subjects. The purpose of this study was to distinguish arthritis with active inflammation from those without active inflammation and to correlate relative intensities of $^{99m}Tc$-labelled HIG uptake of the rheumatoid arthritis with clinical and MR indices of the joint inflammation. This study included twelve patients with active rheumatoid arthritis, two with ankylosing spondylitis and one with degenerative osteoarthritis without active inflammation. A Whole-body and spot images were obtained 4 hours after intravenous injection of 20mCi of $^{99m}Tc$-labelled HIG. Scintigrams were assessed visually by 3 experienced radiologists, and graded as normal or mildly and markedly increased uptake within the joints, and the degree of uptake was compared with clinical and radiologic severity of synovial inflammation. MRI studies were done on the involved joints consisted of wrist(n = 11), knee(n = 2) and hip joint(n= 2). Active synovitis was defined when marked elevation of ESR and gadolinium enhancement of synovium on MRI were demonstrated. Markedly increased radiotracer uptake was seen in 10 of 11 rheumatoid arthritic patients with active synovitis whereas normal or mildly increased uptakes were noted in others, including rheumatoid arthritic patient(n=1) and non-rheumatoid patients(n = 3) without active synovitis. This study showed that the localization of involved joints in rheumatoid arthritis could be detected with $^{99m}Tc$-labelled HIG and that the degree of uptake correlated well with the degree and activity of inflammation. In conclusion, $^{99m}Tc$-labelled HIG scan is a useful method in the evaluation of active inflammation in rheumatoid arthritis.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.20 no.1
• /
• pp.28-31
• /
• 2016

Purpose $^{223}Ra-Dichloride$ is used for the medicine of castration-resistant prostate cancer (CRPC) and which emits ${\alpha}-ray$ of 28 Mev that is used for therapy. However $^{223}Ra-Dichloride$ emits ${\beta}-ray$ of 3.6% and ${\gamma}-ray$ of 1.1%(80,156,270 keV) aside from ${\alpha}-ray$ in decay. Therefore we would like to evaluate external radiation expose dose rate of ${\gamma}-ray$ of $^{223}Ra-Dichloride$. Materials and Methods We calculated external radiation expose dose rate using ${\gamma}-constant$ of $^{223}Ra-Dichloride$, $^{99m}Tc$ based on Health physics(2012). $^{223}Ra-Dichloride$ of 3.5 MBq and $^{99m}Tc-MDP$ of 740 MBq were applied. external radiation expose dose rate 15 times from 1m by survey meter. Results ${\gamma}-contant$ of $^{223}Ra$, $^{99m}Tc-MDP$ from 1m distance based on Health physics(2012) is 0.0469, 0.0215. calculated value of external radiation expose dose rate was $16{\mu}Sy$, $34{\mu}Sy$ which activity is $^{223}Ra-Dichloride$ of 3.5 MBq and $^{99m}Tc-MDP$ of 740 MBq from 1 m and measured mean value of 1 m was $0.7{\mu}Sy/h$, $18{\mu}Sy/h$. Conclusion ${\gamma}-constant$ of $^{223}Ra$ is higher than $^{99m}Tc$ based on Health physics(2012). however calculated maximum external radiation expose dose rate of $^{223}Ra-Dichloride$ is lower than $^{99m}Tc$ due to actually used quantity of activity of $^{223}Ra-Dichloride$ is small. measured value of $^{223}Ra-Dichloride$ is also lower than $^{99m}Tc-MDP$. Therefore external radiation expose dose rate of ${\gamma}-ray$ of $^{223}Ra-Dichloride$ is very low.

• The Korean Journal of Nuclear Medicine
• /
• v.32 no.2
• /
• pp.161-167
• /
• 1998

Purpose: Segmental parenchymal excretion delay on Tc-99m DISIDA scan is caused by intrahepatic bile duct obstruction. However, the diagnostic value for intrahepatic bile duct obstruction is unknown. We conducted this study to assess the positive predictive value of segmental excretion delay for the diagnosis of intrahepatic bile duct obstruction, and additional benefit over other noninvasive radiologic studies. Materials and Methods: The study population consisted of 43 patients (48 scans) who showed segmental parenchymal excretion delay on Tc-99m DISIDA scan. The results of abdominal CT or ultrasonography, which was done within 1 month of Tc-99m DISIDA scan, were compared with scintigraphic findings. Results: The etiology of segmental parenchymal excretion delay was determined by ERC or PTC in 31 scans, and follow-up studies in 13 scans. No causes were identified in 4 scans. The positive predictive value of segmental parenchymal excretion delay for intrahepatic bile ductobstruction was 92% (44/48). On the other hand, 13% (5/38) of CT and 28% (5/18) of ultrasonography were normal. In 18% (7138) of CT and 17% (3/18) of ultrasonography, only intraheipatic bile duct dilatation was noted without any diagnostic findings of intrahepatic bile duct obstruction. Conclusion: Segmental parenchymal excretion delay on Tc-99m DISIDA scan had a high positive predictive value for the diagnosis of intrahepatic bile duct obstruction. Tc-99m DISIDA scan may be useful for the diagnosis of intrahepatic bile duct obstruction, especially in patients with nondiagnostic CT or ultrasonography. The diagnostic usefulness need to be confirmed by further prospective studies.