• Journal of Pharmaceutical Investigation
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• v.31 no.2
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• pp.73-80
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• 2001

Lung perfusion scanning, invariably combined with ventilation studies provides a reliable and non-invasive mean to diagnose lung related pathologies despite the availability of modern techniques such as angiography, magnetic resonance imaging, magnetic resonance angiography, and helical (spiral) computed tomography. The technique involves the generation of images by radiations emitted from radioisotopes introduced in to the lungs. Various radiopharmaceuticals have been proposed and designed to incorporate $Tc^{99m}$ in to macroparticulate form for lung perfusion imaging. However, most of these have associated difficulties such as reproducibility of the product with regards to particle size distribution and poor elimination from the lung capillary bed. $Tc^{99m}$ macroaggregated albumin $(Tc^{99m}-MAA)$ is used extensively for clinical lung perfusion imaging and is considered as the radiopharmaceutical of choice. It is non-toxic, safe, and being biodegradable, is easily eliminated from the lung capillary bed by proteolytic enzyme metabolism and by mechanical forces due to lung movement.

• The Korean Journal of Nuclear Medicine
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• v.27 no.1
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• pp.18-21
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• 1993

이상에서 $^{99m}Tc$-MAA 도관스캔을 고찰하여 보면 다음과 같이 요약할 수 있다. 1) $^{99m}Tc$-MAA 도관스캔은 반복 시행할 수 있고, 그 방법이 간단하나 도관의 위치를 알아내는데 매우 정확하다. 2) 방사선학적 방법인 혈관조영술은 조영제 주입시 실제 항암제를 주입하는 속도보다 매우 빠르게 주입하므로써 야기될 수 있는 동맥의 연축(spasm), 층류 등의 원인에 의하여 항암제를 주입할 때와 다른 양상을 보여 암종의 헐류분포나 주변의 다른동맥으로 항암제가 주입 되는지의 여부를 정확히 알 수 없는 반면, $^{99m}Tc$-MAA 도관스캔은 항암제 주입속도와 동일하게 주입하므로써 보다 정확하게 암종의 혈류분포나 부작용을 예측할 수 있다. 3) 골반내 종양의 경우와 같이 도관을 양측의 동맥에 삽입하여야 하는 경우에는 암종에 대한 각 동맥으로부터의 혈류분포를 비교하여 항암제의 투여량을 변화시키므로써 치료효과의 상승과부작용의 감소를 꾀할 수 있다. 나아가서 둔부동맥으로의 혈류가 많은 경우에는 둔부동맥을 색전화하여 부작용을 극소화할 수도 있다. 4) 여러 종류의 종양, 특히 간종양의 경우에는 폐의 방사능섭취를 측정하여 종양내 동정맥단락을 정량화 할 수 있어 치료후 그 변화를 관찰하여 치료효과를 추측할 수도 있다.

• Tuberculosis and Respiratory Diseases
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• v.50 no.1
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• pp.117-121
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• 2001

Pleural effusion due to hepatic cirrhosis with ascites is well known, although hepatic hydrothorax in the absence of ascites is a rare condition, the pathogenesis of which is still unknown. We report a case of hepatic hydrothorax without ascites confirmed by the intraperitoneal injection of Tc-99m mecroaggregated serum albumin (Tc-99m MAA) that demonstrated the passage of Tc-99m MAA into the right pleural cavity.

• The Korean Journal of Nuclear Medicine
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• v.19 no.2
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• pp.65-68
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• 1985

The radioisotope study using $^{99m}Tc-macroaggregated$ Albumin is a simple, non-invasive test for the diagnosis of pulmonary arteriovenous fistula(PAVF). It can show the presence. of the right-to-left shunt at the lung level using the dynamic study, and also the shunt fraction can be estimated. Here we presented the results of the radioisotope study on two patients with PAVF. In one patient, the cardiac catheterization was clone and calculated shunt fractions by both method were well matched.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.155-158
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• 2010

Purpose: $^{99m}Tc$-macroaggregated albumin (MAA) hepatic arterial perfusion scintigraphy was known for useful method to evaluate patients receiving intraarterial chemotherapy for liver cancer. This study evaluate about usefulness of normal liver on hepatocellular carcinoma (HCC) from HCC patients. This study is to see the usefullness of Hepatic Arterial Perfusion Scintigraphy (HAPS) by measuring mass size, shape, lung shunting and tumor to normal ratio (T/N ratio) in relative blood stream of HCC patients compared with HCC on normal liver. Materials and Methods: From June 2009 to September 2009, HAPS studies were performed on 7 patients (men 6, women 1, mean 64) who were diagnosed HCC. HAPS was performed after proper hepatic artery $^{99m}Tc$-MAA of 5 mCi (185 MBq) injection by catheter. We performed anterior, posterior, both lateral view, SPECT of chest and abdomen. Then we set up ROI and calculated lung shunting, T/N ratio for each count, count/pixel (mean value). Results: Tumor and liver size analyzed by ROI of anterior, posterior view are 2.0-10.8 cm (mean 3.75 cm), 8.8-18.5 cm (mean 14.6 cm). T/N ratio analyzed by total tumor and total normal mean value are 2.41-5.76 (mean 3.8). lung shunting analyzed by total liver count is 3.14-13.92% (mean 6.77%). Conclusion: HAPS with $^{99m}Tc$-MAA can evaluate mass size, location, quantitative analysis through T/N ratio. also HAPS can evaluate detection of arteriovenous shunt through lung uptake before radioisotope therapy. Therefore HAPS with $^{99m}Tc$-MAA can be useful method in aspect of evaluation and treatment of HCC.

• The Korean Journal of Nuclear Medicine
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• v.28 no.3
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• pp.350-356
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• 1994

Purpose : Hepatic arterial perfusion scintigraphy with Tc-99m-macroggregated albumin (HAPS) study was carried out in 16 patients with hepatocellular carcinoma(HCC) and in six patients without liver tumor to evaluate HAPS findings of hepatocellular carcinoma and usefullness of HAPS. Materials and Methods : HAPS with planar and SPECT study were performed in 22 patients after conventional hepatic or celiac arteriography. For HAPS study, 4-5 mCi of MAA mixed with 2ml of saline was injected into proper hepatic artery or its distal branches at the rate of approximately 1ml/sec. We analysed 21 HCCs over 2cm in diameter(average diameter; 6.4cm) and 17 of 21 HCCs were over 4cm in diameter(Table 1). CT, sonography and angiography were performed within two week in all 16 patients and liver scan was performed in 12 patients. Results : Three different pattern of tumor perfusion were observed in 16 patients with HCC (Table 2). 1) diffuse increased perfusion in 16 of 21(76%)(Fig. 1) 2) increased peripheral perfusion in 4 of 21(19%) (Fig. 2) 3) diffuse decreased perfusion in 1 of 21 (5%) Arteriovenous shunt indicated by lung uptake of MAA were observed in 9 of 16(56%)(Fig. 4). In contrast, angiography demonstrates arteriovenous shunt in 2 of 16(13%). There was no accumulation of radioactivity on RBC-blood pool scan in all six patients with HCC examined (Fig. 1). Conclusion : HAPS is useful study in evaluation of perfusion pattern or vascularity of HCC and in detection of arteriovenous shunt.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.7 no.1
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• pp.50-55
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• 2021

Low-dose radiotherapy has been known to have anti-inflammatory activity and been used for treatment of pneumonia together with anti-serum and sulfanilamide. However, it rapidly discontinued after the development of various antibiotics showing outstanding effect. Recently, it was re-considered to treat COVID-19 which has very limited treatment such as remdesivir and dexamethasone. So, several studies of COVID-19 therapy using low-dose radiation were reported very recently. They showed that low-dose radiation of 0.5~1.5 Gy were useful for decreasing the oxygen consumption and hospitalization period of COVID-19 patients without adverse reaction. Radiopharmaceuticals such as [⁹⁹mTc]Tc-macroaggregated albumin (MAA) also might be used for low-dose radiotherapy. Administration of vitamin D having anti-inflammatory effect would also be helpful for therapy with synergistic effect.

• The Korean Journal of Nuclear Medicine
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• v.20 no.2
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• pp.73-78
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• 1986

Of 18 patients with Takayasu's arteritis who underwent $^{99m}Tc-MAA$ (macroaggregated albumin) perfusion luing scanning, 9 (50%) showed perfusion defects. Chest X-rays of them were nonspecific. One patient underwent $^{99m}Tc-DTPA$ radio aerosol inhalation lung scanning simultaneously, which revealed normal. So routine screening radioisotope perfusion lung scanning is helpful to evaluate pulmonary arterial involnmement in Takayasu's arteritis patients. And Takayasu's arteritis should be included in differential diagnosis of pulmonary embolism.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.1
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• pp.28-32
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• 2006

Purpose: Conventional chest X-ray and pulmonary function test cannot sensitively detect inhalation injury. Bronchoscopy is known to be the gold standard but it is invasive method. We evaluated whether lung inhalation/perfusion scans can sensitively detect inhalation injury of fire victims. Materials and Methods: Nineteen patients (male 9, female 10, mean age 31.6 yr) of fire victims were enrolled in this study. Inhalation lung scan was performed 2 days later after inhalation injury with $^{99m}Tc$-technegas. Perfusion lung scan was performed 4 days later with $^{99m}Tc$- MAA (macroaggregated albumin). Follow up lung scans were performed 16 and 18 days later for each. Chest X-ray was performed in all patients and bronchoscopy was performed in 17 of 19 patients at the same period. Pulmonary function test was performed in 9 patients. Results: Four of 19 patients showed inhalation and perfusion defects and one showed inhalation defect but, normal perfusion scan findings. These five patients with abnormal scan findings showed abnormal bronchoscopic findings and severe respiratory symptoms. On chest X-ray, 2 of them had pulmonary tuberculosis and one of them showed pulmonary congestion. FEV1 /FVC was abnormal in 3 patients. On the follow up scan, all patients with abnormal initial scan findings showed improved findings and they had improved clinical state. Conclusion: Inhalation/perfusion lung scans can detect inhalation burn injury noninvasively in early stage and may be useful in therapeutic decision making and follow up of patients.

• Clinical and Experimental Pediatrics
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• v.50 no.10
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• pp.1030-1033
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• 2007

A pulmonary thromboembolism (PTE), which is a sudden blockage in a pulmonary artery, usually due to a blood clot, is rare in children. The clinical presentation is often subtle or masked by the underlying clinical condition and the condition must be suspected during clinical testing. Although the choice of treatment depends on the clinical presentation, anticoagulation is the mainstay of therapy for children with PTE. We report the case of a healthy 1-month-old boy who presented with hemoptysis without hemodynamic instability. He was diagnosed based on chest computed tomography with angiography and 99mTc macroaggregated albumin lung perfusion scintigraphy and treated with low-molecular-weight heparin.