• The Korean Journal of Nuclear Medicine
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• v.33 no.6
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• pp.519-526
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• 1999

Purpose: This study was designed to evaluate the usefulness of a technetium-99m mercaptoacetyltriglycine (Tc-99m MAG3) single photon emission computed tomography (SPECT) performed on transplanted kidney. Materials and Methods: Thirty renal transplant patients were included in this study. Planar scan was performed for 30 minutes using 555 MBq Tc-99m MAG3. A post-voiding SPECT scan was acquired on the third, seventh, fourteenth and twenty eighth day after transplantation. Results: SPECT scan showed interpretable image quality in 26 of 30 patients (86.7%) and 84 in 120 scans (70%). Fourteen of 26 patients with interpretable SPECT image showed decreased or increased radioactivity, but only 5 had abnormal findings on the planar scan. Focal SPECT defects were seen in allografts with normal function (n=3), acute tubular necrosis (n=3), and acute rejection (n=2). The defects are thought to reflect focally underperfused renal parenchyme or, in normal allografts, an artifact from uneven radioactivity distribution. Four of 10 patients with renal arterial variation showed focally decreased radioactivity and SPECT helped guide funker studies that confirmed the exact cause. Five of 10 patients with acute tubular necrosis or acute rejection showed focally decreased radioactivity, but its relation to the patients' clinical course was not clear. Focally increased radioactivity was observed in 5 allografts with normal function and 1 with double ureter in which local clearance delay was observed. Conclusion: Tc-99m MAG3 SPECT renal scan can detect additional focal abnormalities compared to planar scan. Further study is necessary to elucidate the exact clinical significance of the SPECT findings.

• The Korean Journal of Nuclear Medicine
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• v.24 no.1
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• pp.74-79
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• 1990

$^{99m}Tc-MAG_3$ was synthesized, and biodistribution and blood clearance rate were compared with those of $^{131}I-OIH$ in mice and rats respectively. Finally renal image was obtained from a normal male volunteer before and after prescription of probenecid. The results obtained were as follows: 1) The uptake of $^{99m}Tc-MAG_3$ by kindey was higher than that of $^{131}I-OIH$ in mice 10 mins after injection (n=6, p<0.05), but slightly lower uptakes were found in all organs (kindney, blood, stomach, intestinge and liver) 2 hrs after injection. 2) For $^{99m}Tc-MAG_3$ $4\frac{1}{2}\;\alpha=2.4{\pm}0.0\;min,\;t\frac{1}{2}\;\beta=44.3{\pm}7.4\;min$, and blood clearance=$3.4{\pm}0.5ml/min$, and for $^{131}I-OIH\;t\frac{1}{2}\;\alpha=1.8{\pm}0.2\;min,\;\beta=69.1{\pm}9.5\;min$, and blood clearance=$1.3{\pm}0.1\;min$ were found in rats. 3) From the renogram of normal male volunteer, we could find that tmax=130 sec and $t\frac{1}{2}=430\;sec$ before probenecid prescription, and $tmax=150\sim170$ sec and $t\frac{1}{2}=810\sim1,170$ sec after probenecid prescriprion. From these results we concluded that $^{99m}Tc-MAG_3$ can be used instead of $^{131}I-OIH$ for obtaining renal image.

• Environmental Mutagens and Carcinogens
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• v.21 no.1
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• pp.1-8
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• 2001

We have synthesized $^{99m}$Tc-mercaptoacetyltriglycine (MAG3)-biocytin as a new imaging agent for hepatobiliary scintigraphy. The aim of this study was to evaluate the usefulness of $^{99m}$Tc-MAG3-biocytin scintigraphy in differentiating carbon tetrachloride ( $CCl_4$)-induced hepatotoxicity from $\alpha$-naphthylisothiocyanate (ANIT)-induced cholestasis in mice, which reflecting the differential diagnosis of neonatal jaundice caused by neonatal hepatitis from congenital biliary atresia in humans. Methods: Balb/c mice (female, 20 g, n=4-6) were pretreated with $CCl_4$(0.5 or $1.0m\ell$/kg) and ANIT ($150 or 300 m\ell$/kg) 18 h before scintigraphy. Biochemical and histopathological examinations showed a pattern of typical acute hepatitis (increase of transaminases and hepatocellular necnsis) in $CCl_4$-treated mice and cholestasis (increase of alkaline phosphatase and ${\gamma}$-glutamyltransferase, and biliary hyperplasia) in ANIT-treated mice, respectively, Mice were fasted at least 4 hr prior to the intravenous injection of $^{99m}$Tc-MAG3-biocytin (18.5 MBq/20$\mu\textrm{g}$) in 2% human serum albumin in saline. Scintigraphy was performed with a ${\gamma}$-camera equipped with a 1-mm diameter pin-hole collimator for 30 min and images were acquired every 15 s. We compared the values of physical parameters, such as peak liver/heart ratio ($${\gamma}$_{max}$) and peak ratio time ($t_{max}$) far $^{99m}$Tc-MAG3-biocytin scintigraphy. Results: Scintigraphic parameters of the $CCl_4$-pretreated (0.5 $m\ell$/kg) group showed a 81.9% decrease of r$_{max}$, and 42.2% decrease of $t_{max}$, whereas the ANIT-pretreated ( $150m\ell$/kg) group showed a 53% decrease of $r_{max}$, and 2.36-fold increase of $t_{max}$, (P<0.05). These results demonstrate that the decrease of $r_{max}$ and the shortening of $t_{max}$ are characteristic features for hepatotoxicity, in contrast to the increase of $t_{max}$ and decrease of $r_{max}$ for biliary hyperplasia. Conclusion: $^{99m}$Tc-MAG3-biocytin hepatobiliary scintigraphy can distinguish hepatitis from cholestasis in mice model and may be similarly useful in humans which differentiating the cause of neonatal jaundice in clinical study.cal study.cal study.cal study.

• The Korean Journal of Nuclear Medicine
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• v.36 no.5
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• pp.306-313
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• 2002

Purpose: Diuretic renography (DR) can be false negative in patients with upper urinary tract obstruction due to low compliance of the renal pelvis. Delayed parenchymal transit (DPT) may be a valuable sign in case of false negative DR. We compared the diagnostic values of DR and DPT during Tc-99m MAG3 diuretic scan in adults with suspected unilateral obstructive uropathy. Materials and Methods: Fifty-four patients(male:female=30:24, age: $40.7{\pm}15.5$ yrs) who underwent Tc-99m MAG3 diuretic scan due to suspicious unilateral obstructive uropathy were analyzed. DR with a $T_{1/2}\;of\;>\;15min$ was considered as positive for obstruction. DPT was considered to be present when there was delayed appearance of radioactivity in the renal pelvis and prolonged retention of radioactivity in the renal parenchyma. The renal area ratio was defined as the ratio of pixel number of hydronephrotic kidney over that of normal contralateral at $1{\sim}2min$ images. Definition of obstruction was improved hydronephrosis after intervention, or aggravated hydronephrosis without intervention. Non-obstruction was defined as unchanged hydronephrosis over 6 months. Results: Twenty-six renal units had obstruction and 28 no obstruction. The sensitivities of DR and DPT were 69% (18/26) and 50% (13/26) respectively. Two renal units with DPT but negative DR showed the renal area ratio of <1.1. Among the 20 obstructive renal units with DPT or positive DR, 13 with DPT had lower renal area ratio than 7 renal units without DPT ($0.97{\pm}0.20\;vs\;1.30{\pm}0.41,\;p<0.05$). Differential renal function was not significantly different between these groups. DPT correctly diagnosed all renal units with non-obstruction (specificity 100%), while the specificity of DR was 89% (25/28). Conclusion: DPT during Tc-99m MAG3 diuretic scan may be a valuable sign in diagnosing urinary obstruction especially in patients with false negative DR and early HN.

• Journal of radiological science and technology
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• v.39 no.2
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• pp.199-208
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• 2016

$^{99}mTc-MAG_3$ Renal scan is a method that acquires dynamic renal scan image by using $^{99}mTc-MAG_3$ and dynamically visualizes process of radioactive agent being absorbed to kidney and excreted continuously. Once the test starts, ratio in both kidneys in 1~2.5 minutes was measured to obtain split renal function and split renal function can be expressed in ratio based on overall renal function. This study is based on compares split renal function obtained from data acquired from posterior detector, which is a conventional renal function test method, with split renal function acquired from the geometric mean of values obtained from anterior and posterior detectors, and studies utility of attenuation compensation depending on difference in geometric mean kidney depth. From July, 2015 to February 2016, 33 patients who undertook $^{99}mTc-MAG_3$ Renal scan(13 male, 20 female, average age of 44.66 with range of 5~70, average height of 160.40cm, average weight of 55.40kg) were selected as subjects. Depth of kidney was shown to be 65.82 mm at average for left and 71.62 mm at average for right. In supine position, 30 out of 33 patients showed higher ratio of deep-situated kidney and lower ratio of shallow-situated kidney. Such result is deemed to be due to correction by attenuation between deep-situated kidney and detector and in case where there is difference between the depth of both kidneys such as, lesions in or around kidney, spine malformation, and ectopic kidney, ratio of deep-situated kidney must be compensated for more accurate calculation of split renal function, when compared to the conventional test method (posterior detector counting).

• The Korean Journal of Nuclear Medicine
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• v.34 no.6
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• pp.497-507
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• 2000

Purpose: We have examined the utility of $^{99m}Tc$-MAG3 perfusion indices for assessing renal graft function in early post-transplantation period. Materials and Methods: Our study included 80 renal transplant recipients (48 men and 32 women, mean age: 40.3 years). Diagnosis was based on biopsy, laboratory data and clinical course. Renal scintigraphy (RS) was obtained using 100 MBq of $^{99m}Tc$-MAG3 from 11 days to 23 days of kidney transplantation. We measured 5 indices in whole-kidney (WK) and cortical (C) renograms; Hilson's perfusion index (PI), transplant perfusion index (TP) and transplant function index (TF) as perfusion parameter, and the time to peak activity (Tmax) and the ratio of renal counts at 20 min to that at 3 min (K20/3) as functional parameter. Results: The diagnoses at the day of RS were normal graft (NG) in 44, acute rejection (AR) in 14, acute tubular necrosis (ATN) in 10, and Cyclosporine A nephrotoxicity (CsA) in 12. TP and TF were significantly decreased in AR, ATN and CsA, compared to those in NG. K20/3 of AR and ATN wore significantly greater than that of NG. WK-Tmax of AR was significantly longer than that of NG. K20/3 of AR and C-K20/3 of ATN were significantly prolonged relative to those of CsA. There were no statistically significant perfusion indices among complication groups. Conclusion: TP and TF reflecting microperfusion and initial tubular extraction are reliable in assessing graft function. However, it is required to correlate perfusion indices with functional indices and clinical course in differentiating from one another among complication groups.

• The Korean Journal of Nuclear Medicine
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• v.29 no.1
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• pp.79-83
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• 1995

Purpose : We analysed $^{99m}Tc-MAG_3$ renal scans to evaluate renal function of transplanted kidney and to detect various renal transplant complications, measuring the ratio of renal radioactivity at three minutes to that at 20 minutes(elimination index). Material and Methods : The fifty seven renal transplantation recipients were studied. There were 50 normal functioning transplanted kidneys as group I and 7 abnormal function-ing transplanted kidney, including 5 cases of acute renal rejection, 2 cases of acute tubular necrosis as group IIl. The protocol consisted of: (1) $^{99m}Tc-MAG_3$ 740MBq injection intravenously : (2) sequential imaging for 2min(60two-second images) followed by 30min(30 sixty-second images) : (3) drawing of region of interest(ROI) on renal imaging; (4) time-activity corves were generated from renal ROI after background subtraction, and time of maximum activity($T_{max}$) and half time of maximal peak radioactivity($T_{1/2}$) were produced in the renogram curve. (5) EI through Bischof-Delaloye method as determined on the renogram curve. Results : Normal group( I ) shows mean EI of 2.21(95.0% Confidence limit of 2.01-2.87), $T_{max}$ of 154 sec, $T_{1/2}$ of 1,139 sec. Abnormal group(II) shows mean EI of 0.74, $T_{max}$ of 1,466 sec, $T_{1/2}$ of 19,224 sec. The EI, $T_{max}$, $T_{1/2}$, BUN and serum creatinine values are significantly different between normal group(I) and abnormal group(II) (p<0.0001). Conclusion : By measuring EI with $^{99m}Tc-MAG_3$, renal function of transplanted kidney could be easily evaluated and various complications could be detected early.

• 대한핵의학회:학술대회논문집
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• 1989.06a
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• pp.136.2-137
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• 1989

• The Korean Journal of Nuclear Medicine Technology
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• v.20 no.1
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• pp.59-65
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• 2016

Purpose Dynamic kidney scan is a typical imaging technique that visualizes kidney function. Reproducibility of dynamic kidney scans has been evaluated by comparing low-dose kidney scans with low-dose radiopharmaceutical and standard dynamic kidney scan. With this comparative study, if reproducibility is superb, the dynamic kidney scan method with reduced radioactivity to patients is to be utilized and radiation exposure to patient is to be reduced. Materials and Methods For gamma camera, Orbiter, SymbiaE (Siemens, Germany) was used. Among patients who had used 370 Mbq (10 mCi) from January of 2013 to February 2014 and other patients who had used 185 Mbq (5 mCi) from March of 2014 to July of 2015 with identical condition, 21 subjects using DTPA and 20 subjects using $MAG_3$, 41 subjects in total, had been selected as subjects for data. From renogram of the result image, frame of the peak point was selected. Then, region of interest of kidney and background had been selected and Kidney to Background Ratio has been calculated for comparison. Results In tests using DTPA, kidney to background ratio when using 370 Mbq was $5.67{\pm}0.8$ at average while it was $5.62{\pm}0.87$ when using 185 Mbq, which didn't show much difference. Also in the tests using $MAG_3$, kidney to background ratio when using 370 Mbq was $14.95{\pm}2.58$ at average and $14.56{\pm}2.02$ in 185 Mbq, which neither showed much difference. In paired sample t-test, p-value was 0.566 in DTPA and 0.363 in $MAG_3$, which confirmed that there was no difference between the groups. Conclusion In identical patients, when dose was decreased from 370 Mbq to 185 Mbq, reproducibility of dynamic kidney scan was proven to be excellent. Low-dose Dynamic kidney scan can achieve results with fine reproducibility without improvement in performance of gamma camera and is expected to reduce radiation exposure to patient.

• 대한핵의학회:학술대회논문집
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• 1999.11a
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• pp.18.2-18.2
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• 1999