Coexisting renal vein thrombosis and bilateral adrenal hemorrhage: renoscintigraphic demonstration

A rare case of simultaneous renal vein thrombosis and bilateral adrenal hemorrhage is presented, showing the utility of Tc-99m DTPA and DMSA renal scans to identify the condition and to assess renal function. The characteristic appearances of suprarenal tracer-free areas encircled by peripheral radioactive rims over the inferiorly displaced kidneys on a Tc-99m DTPA renal scan, and that of the flattened upper poles of the kidneys on a Tc-99m DMSA scan, were pathognomonic and strongly indicative of bilateral adrenal hemorrhage. These two scans also showed markedly diminished tracer uptake in the poorly functioning right thrombosed kidney. Follow-up imaging using these two renal scans well demonstrated the functional and morphologic alterations and recovery of the kidneys.     

Increased bone marrow uptake on Tc-99m DMSA scintigraphy in a patient with renal osteodystrophy

A 16-year-old male patient was evaluated with Tc-99m Diethylenetriamine-pentaacetic acid (DTPA) and Tc-99m 2–3 Dimercaptosuccinic acid (DMSA) scintigraphy for renal failure secondary to renal calculi. The uptake in the renal cortex was significantly decreased both on DMSA and DTPA studies. Uptake calculation on DMSA scintigraphy in the kidneys disclosed values of less than 5 %. The activity in the liver and bone was significantly increased. A bone scan performed with Tc-99m methylene diphosphonate (MDP) revealed increased bone uptake with decreased soft tissue activity. Findings on bone scan were compatible with super scan, most likely due to renal osteodystrophy. This case illustrates the altered biodistribution of Tc-99m DMSA and a shift of the radiopharmaceutical to the bone marrow which is mot likely related to colloid formation due to changes in mineral balance in patients with renal failure.     

The role of Tc-99m (V) DMSA scintigraphy in the evaluation of superscan on bone scintigraphy

PURPOSE: This study evaluated the biodistribution of Tc-99m (V) DMSA in patients with superscans on bone imaging and defined its role in differentiating the underlying cause. METHODS: Nine patients (five with metastatic and four with metabolic bone disease) with classical superscans were entered into the study. All patients had the necessary radiologic and biochemical studies and a final diagnosis was reached accordingly. Tc-99m (V) DMSA scintigraphy was performed 1 week after Tc-99m MDP whole-body bone imaging. RESULTS: In four of five patients with widespread skeletal metastases, Tc-99m (V) DMSA scan showed diffusely increased bone uptake. In the remaining patient, the Tc-99m (V) DMSA scan showed a normal distribution pattern. All patients with metabolic bone disease had increased bone uptake on Tc-99m (V) DMSA scans. CONCLUSION: Tc-99m (V) DMSA shows increased bone uptake in patients having a superscan appearance in metastatic or metabolic bone disease. Tc-99m (V) DMSA imaging may play a role in the evaluation of patients with equivocal bone scan findings for a superscan.     

Simultaneous demonstration of pleural effusion and ascites by technetium-99m sulfur colloid liver-spleen scintigraphy

Scintigraphic evidence of ascites has been observed in Tc-99m sulfur colloid studies of the liver and spleen, in Tc-99m HIDA hepatobiliary scans, in Ga-67 citrate scans, and in Tc-99m phosphonate bone images. Pleural effusion has been demonstrated in Tc-99m phosphonate bone scintigraphy. The case of a 48-year-old man whose Tc-99m sulfur colloid liver-spleen scintigram simultaneously demonstrated a right pleural effusion and ascites is presented.     

Effectiveness of diuretic injection on the measurement of differential renal function using Tc-99m DMSA in patients with a dilated renal pelvis

AIM: The aim of this study was to evaluate the effectiveness of diuretic injection for the measurement of differential renal function (DRF) with technetium-99m dimercaptosuccinic acid (Tc-99m DMSA) scintigraphy in patients with a dilated pelvis. MATERIALS AND METHODS: A total of 46 patients who were referred for both technetium-99m-L,L-ethylenedicysteine (Tc-99m L,L-EC) and Tc-99m DMSA imaging and found to have a dilated collecting system on Tc-99m EC scintigraphy were studied. Four to 5 hours after intravenous injection of Tc-99m DMSA, imaging was performed in the supine position, and posterior, anterior, left and right lateral, and left and right posterior oblique views were taken. After this study, furosemide was administered intravenously and 30 minutes later, additional images in the anterior and posterior views were obtained. RESULTS: The kidneys were evaluated into 2 groups. Group 1 comprised 12 kidneys that had an obstructive curve pattern on Tc-99m EC scans. Group 2 comprised 34 kidneys that had a nonobstructive dilated renogram curve pattern. DRF of the kidneys in each patient were calculated, and the values obtained from the standard and diuretic DMSA scans were compared with each other for all patients and each group. Considering all the patients, the values of mean DRF on both standard and diuretic DMSA images were 55.4%+/-21.2% and 55.4%+/-21.5%, respectively. There were no significant differences between DRF values of each kidney obtained by the 2 methods. When we compared the DRF values in groups 1 and 2, there were again no significant differences. In group 1, the values of mean DRF on standard and diuretic images were 51.7%+/-13.7% and 51.6%+/-13.9%, respectively, and in group 2, the values of mean DRF were 56.7%+/-23.4% and 56.7%+/-23.6%, respectively. CONCLUSION: In view of our study, diuretic administration seems to be an unnecessary intervention because it has no effect on the accuracy of DRF measurements using DMSA scintigraphy in patients with a dilated collecting system whether it is obstructed or not.     

Technetium-99m-<Emphasis Type="Italic">N,N</Emphasis>-ethylenedicysteine and Tc-99m DMSA scintigraphy in the evaluation of renal parenchymal abnormalities in children

Technetium-99m dimercaptosuccinic acid (Tc-99m DMSA) as a static renal agent is currently the most frequently used agent in the detection of renal scarring, and allows accurate calculation of differential renal function (DRF). But this agent has some disadvantages such as relatively higher radiation dose and time consumption. METHODS: The purpose of this study was to evaluate the potential of summed image that obtained from parenchymal phase of the dynamic technetium-99m-N,N-ethylenedicysteine (Tc-99m EC) scintigraphy in the detection of renal parenchymal defects and in the estimation of DRF, and to compare the results of this method with those of Tc-99m DMSA scintigraphy. The uptake ratios of the kidney to body background were also calculated for these two methods. Twenty-nine children with various renal disorders underwent both static Tc-99m DMSA and dynamic Tc-99m EC scintigraphy. The cortical analysis of Tc-99m EC scintigraphy was performed on the summed image obtained from dynamic images using the time interval between the first 45-120 sec. RESULTS: There was a very close correlation between these two methods with respect to DRF (r = 0.99). In the detection of renal parenchymal lesions, scintigraphy with Tc-99m DMSA detected more lesions, and the sensitivity and specificity of the summed Tc-99m EC images were calculated as 92.6% and 100%, respectively. In addition, the ratios of mean uptake values for Tc-99m DMSA and Tc-99m EC images were 7.59 +/- 2.17 and 2.95 +/- 0.91, respectively. This ratio of Tc-99m EC seems to be acceptable and allows good delineation of the kidneys. But, the main disadvantages of the summed Tc-99m EC images in comparison with static Tc-99m DMSA images are the use of only posterior projection that may be an important drawback in patients with abnormal kidney positions, lower image counts and higher pixel size because of dynamic acquisition. CONCLUSION: These results show that summed Tc-99m EC images with an acceptable high image contrast provide an accurate DRF calculation in patients without abnormal kidney positions and allow the detection of most renal parenchymal abnormalities. However, Tc-99m DMSA scintigraphy remains the gold standard method because of its well known advantages.     

Role of technetium-99m N,N-ethylenedicysteine renal scintigraphy in the evaluation of differential renal function and cortical defects

PURPOSE: This study was performed to evaluate the effectiveness of technetium-99m N,N-ethylenedicysteine (Tc-99m EC) in comparison to technetium-99m dimercaptosuccinic acid (Tc-99m DMSA) scintigraphy. Differential renal function (DRF) was calculated by both methods and the cortical-phase images of dynamic Tc-99m EC scintigraphy were evaluated for parenchymal defects. MATERIALS AND METHODS: A total of 62 patients with various kidney disorders ranging in age from 1 to 44 years underwent both Tc-99m DMSA and Tc-99m EC scintigraphy. Tc-99m EC summed images of the cortical phase and Tc-99m DMSA images were evaluated visually and quantitatively. Visual analysis was used to define renal parenchymal abnormalities. Quantitative analysis was used in the calculation of DRF. The Tc-99m DMSA scan was taken as the gold standard, and the summed Tc-99m EC scan findings were compared against it. RESULTS: The images obtained with Tc-99m DMSA and Tc-99m EC scintigraphy revealed 99 and 97 focal defects, respectively. The 2 renal parenchyma defects located in the ventral middle sections remained undetected with Tc-99m EC scintigraphy. DRF of the kidneys in each patient was compared using both radiopharmaceuticals. Highly positive correlation between the differential function of these 2 investigations was found (R = 0.91, P = 0.001). The values of mean DRF of the left kidney on Tc-99m EC and Tc-99m DMSA images were 45.8 +/- 19.1 and 45.0 +/- 20.4, respectively. There were no significant differences (P > 0.05). CONCLUSION: This study suggests that although Tc-99m DMSA scintigraphy remains the gold standard method for evaluating parenchymal abnormalities, Tc-99m EC scintigraphy can be a reliable single-modality study to evaluate renal cortical defects, DRF, perfusion, drainage of the urinary system, and indirect evidence of vesicoureteric reflux with the added advantage of low radiation exposure to the patient.     

Discordant hepatic uptake of Tc-99m HIDA and Tc-99m colloid in a patient with segmental biliary obstruction

Discordant hepatic uptake between Tc-99m HIDA and Tc-99m colloid occurred in a 63-year-old female with segmental biliary obstruction due to cholangioma. Radiographic CT and a percutaneous transhepatic cholangiogram revealed the obstructed right hepatic duct as well as the dilated intrahepatic duct in the right lobe. At surgery this was confirmed, and a 2 cm mass encasing the right hepatic duct was identified. It should be included in the gamut of discordant hepatic uptake of Tc-99m IDA and Tc-99m colloid.     

Pharmacokinetics of hepatobiliary imaging agents in rats: concise communication.

The distribution and elimination kinetics of Tc-99m pyridoxlidene glutamate (Tc-99m PG), of Tc-99m N-(2,6-dimethyl-phenylcarbamoylmethyl) iminodiacetic acid (Tc-99m HIDA), and of I-131 rose bengal in blood were quantitated after i.v. injection in rats. This was performed by use of a unique indwelling catheter that externalizes the systemic circulation, permitting continuous monitoring of blood radioactivity. The blood activity-time curves of Tc-99m PG and Tc-99m HIDA are described by the sum of three exponential functions. Only two exponentials are required in the case of I-131 rose bengal. The rank order for the rates of loss from blood was Tc-99m HIDA less than Tc-99m PG less than I-131 rose bengal. Bile was collected after administration of Tc-99m HIDA and Tc-99m PG. The total excretion of radioactivity over a 70-min period amounted to 95.7% and 42.8% of the dose of Tc-99m HIDA and Tc-99m PG, respectively. A linear compartmental kinetic model was developed to account for the disappearance from blood and the biliary excretion of these radiopharmaceuticals in rats.     

Tc-99m(V)-DMSA in wound infection after closure of an ileostomy

We present a 71-year-old man who underwent closure of an ileostomy and had a fever seven days post surgery. Both Tc-99m(V)-dimercaptosuccinic acid (DMSA) and gallium-67 citrate scans showed increased tracer accumulation in the right lower quadrant of the abdomen. Tc-99m(V)-DMSA scintigraphy can be a rapid alternative tool in the detection of wound infection in patients after ileostomy closure.     

Power Doppler sonography versus Tc-99m DMSA scintigraphy for diagnosing acute pyelonephritis in children: are these two methods comparable?

PURPOSE This study assessed the role of renal power Doppler ultrasonography (PDU) to identify acute pyelonephritis (APN) and to determine whether PDU can replace Tc-99m DMSA renal scintigraphy in the diagnosis of APN in children.METHODS A prospective study was conducted in 40 infants and young children (78 kidneys were evaluated) with a mean age of 25.9 months (range, 1 to 68 months) who were hospitalized with a first episode of high fever and bacteruria, possibly APN. All children were examined by PDU and Tc-99m DMSA within the first 3 days after admission. Patients with congenital abnormalities, hydronephrosis, and urinary reflux were excluded.RESULTS Twenty-seven of the 78 kidneys appeared abnormal on Tc-99m DMSA, and 20 of them were abnormal on PDU. Fifty-one of 78 kidneys were normal on Tc-99m DMSA, and 3 of 51 appeared diseased on PDU. The accuracy of PDU was 87%, sensitivity was 74%, and specificity was 94%. The positive predictive and negative predictive values were both 87%. When considering the numbers of lesions in 27 kidneys with positive Tc-99m DMSA studies (38 lesions), PDU did not disclose 16 lesions (false-negative results). Thus, the sensitivity of PDU for diagnosing lesions of APN decreased to 58%.CONCLUSIONS A positive PDU finding should obviate the use of Tc-99m DMSA in patients thought to have possible APN. However, because of a large number of false-negative results (26%) and underestimation of the number of pyelonephritic lesions (low sensitivity of 58%), PDU cannot replace Tc-99m DMSA in the diagnosis of APN in children.     

Tc-99m(V) DMSA imaging. A new approach to studying metastases from breast carcinoma.

Combined Tc-99m MDP skeletal imaging and Tc-99m(V) DMSA whole body scans to detect metastases were performed during the follow-up of 30 patients who underwent surgery for breast carcinoma. Eight patients had normal Tc-99m MDP and Tc-99m(V) DMSA scans and were declared free of metastatic disease, further confirmed by no change in symptomatology over a 1-year follow-up period. Twenty-two patients had positive Tc-99m MDP scans with varied skeletal involvement. Tc-99m(V) DMSA scans showed matched areas of increased radiotracer concentration in bony metastases in 20 of these patients. Tc-99m(V) DMSA concentration was not seen in traumatic vertebral collapse or in coexistent osteoarthritic disease in vertebral metastatic involvement. Interestingly, Tc-99m(V) DMSA showed increased concentration in brain and liver metastases. Pentavalent Tc-99m(V) DMSA appears useful for detecting skeletal and soft-tissue metastases in breast carcinoma, and can improve the specificity of Tc-99m MDP bone scans in screening for bone metastases.     

Ectopic ureteroceles in infants with prenatal hydronephrosis: use of renal cortical scintigraphy

PURPOSE: This study assesses the contribution of renal cortical scintigraphy in the diagnostic evaluation of infants with ectopic ureteroceles. METHODS: The records of 20 infants (age range, 3 weeks to 4 months) who were referred for renal cortical scintigraphy after an ectopic ureterocele associated with a duplex kidney was found during follow-up of prenatal hydronephrosis were reviewed retrospectively. All infants underwent voiding cystourethrography, ultrasonography, and Tc-99m DMSA scintigraphy. RESULTS: All upper moieties showed absent or depressed Tc-99m DMSA uptake. Upper moiety functional impairment was associated with structural abnormalities shown by ultrasonography. The degree of functional impairment was reflective of ultrasonographically defined cortical thickness relative to pelvic diameter, but this relation varied. Eight of 20 (40%) lower moieties had diffusely depressed relative Tc-99m DMSA uptake. Focal defects were also present in three of these eight (38%) lower moieties. Lower moiety functional impairment was associated with higher degrees of pelvic dilatation and with vesicoureteral reflux. Ultrasonography revealed diffuse parenchymal thinning in four of the eight (50%) lower moieties with depressed uptake. Ultrasonography did not define focal parenchymal loss in any lower moiety. CONCLUSIONS: The degree to which function is impaired in the upper moieties of duplex kidneys with ureters terminating in ectopic ureteroceles is not highly predictable by ultrasonography. Lower moiety functional impairment and cortical defects are frequently present in these kidneys and often occur without ultrasonographic evidence of parenchymal damage. Use of renal cortical scintigraphy in the diagnostic evaluation of infants with ectopic ureteroceles is supported.     

Unusual Tc-99m MDP and I-123 MIBG images in focal pyelonephritis

A 6-year-old boy presented with an inflammatory syndrome. Because Tc-99m MDP bone scintigraphy revealed increased tracer uptake at the upper pole of the right kidney, further studies were oriented towards a diagnosis of renal or adrenal pathology. I-123 metaiodobenzylguanidine (MIBG) accumulated at the site of the abnormal MDP uptake. The diagnosis of neuroblastoma or allied disorder was excluded on the basis of other investigations and further evaluation, suggesting that the MIBG uptake was a false-positive. Findings on clinical imaging, laboratory findings, Tc-99m DMSA imaging, sonography, and CT scanning were highly suggestive of acute focal pyelonephritis.     

A comparison of the tumor-seeking agent Tc-99m(V) dimercaptosuccinic acid and the renal imaging agent Tc-99m dimercaptosuccinic acid in humans

Being aware of the ideal nuclear properties of Tc-99m, our interest has been focused on the design of the (+5) oxidation state Tc-99m(V) dimercaptosuccinic acid (Tc(V)-DMSA) as a tumor-seeking agent. Tc-99m(V) DMSA holds a TcO4(3-) core and, like PO4(3-), has excellent characteristics for tumor uptake, but has a different distribution than the well-known renal scanning agent, Tc-99m DMSA. The differences in chemical behavior of Tc-99m(V) DMSA and Tc-99m DMSA are discussed. Three cases in which neoplasms were studies with Tc-99m(V) DMSA and Tc-99m DMSA are presented. Tc-99m DMSA and Tc-99m(V) DMSA, having a common ligand and tracer but, with the metal ion core in a different oxidation state, the uptake characteristics are altered markedly.     

Reversed intrapulmonary right-to-left shunt after banding of the patent ductus venosus

Diffuse pulmonary microvascular arteriovenous communication developed in an 8-year-old girl with a patent ductus venosus. Tc-99m macroaggregated albumin (MAA) pulmonary perfusion scintigraphy with total-body imaging demonstrated multiple lung perfusion deficits and abnormal tracer uptake in systemic organs with hepatic radioactivity greater than the kidneys, suggesting the presence of right-to-left shunt and abnormal hepatic hemodynamics. I-123 iodoamphetamine transrectal portal scintigraphy revealed a large portosystemic venous shunt. The follow-up Tc-99m MAA perfusion scans after banding of the patent ductus venosus revealed partial improvement of the perfusion deficits and right-to-left shunt, indicating the possible reversibility of this pulmonary shunt complication.     

The role of Tc-99m (V) DMSA scintigraphy in the diagnosis and follow-up of lung cancer lesions

Objective To define the role of Tc-99m (V) dimercaptosuccinic acid (DMSA) scanning in the detection of lung cancer (LC) and its metastases, and monitoring the response of LC lesions (LCL) to chemo/radiotherapy (TH). Methods Tc-99m (V) DMSA whole-body scans, planar thorax views, and thorax Single-photon emission computed tomography (SPECT) images were obtained both 30 min (early) and 5 h (late) after Tc-99m (V) DMSA administration in 12 small/nonsmall cell LC patients (11 men, 1 woman; mean age 59 years). Five patients also had bone scans. The same scintigraphic protocol was performed in 7 of 12 patients, 3 weeks after first-line TH. TH response was evaluated visually in all LCL and semiquantitatively in primary tumors (PT) of six patients, by comparing the tumor uptake ratios (TUR) of pre-TH and post-TH Tc-99m (V) DMSA SPECT [TUR = mean counts of region of interests (ROI) in PT/mean counts in contralateral ROI]. In seven patients, a 6-month survival was determined. Results Tc-99m (V) DMSA accumulated in 34 LCL (11 PT, 19 bone metastases, 1 suprarenal mass, 1 axillary node, 2 supraclavicular nodes). A total of 11 patients displayed Tc-99m (V) DMSA uptake in LCL and one patient did not show uptake. In six patients, SPECT imaging showed deeply located PT in the lung parenchyma better than planar views. In five patients, both planar and SPECT views revealed peripherally located PT in the lungs. Early scans showed 18 LCL and late scans displayed all the LCL. Nine bone metastases on pre-TH Tc-99m (V) DMSA scans revealed matched areas of increased Tc-99m methylene diphosphonate (MDP) uptake on bone scans; six bone metastases were additionally detected on Tc-99m (V) DMSA scans when compared with bone scans, and four bone metastases on Tc-99m (V) DMSA scans could not be compared with bone scans because bone scan was not performed. In one patient, Tc-99m (V) DMSA scans became positive for bone metastases on post-TH later than the bone scans for some of the bone metastases. Neither planar nor SPECT imaging showed mediastinal lesions defined on thorax CT in nine patients. On TH monitoring, 17 LCL showed diminished Tc-99m (V) DMSA uptake, one disappeared, four were unchanged, three displayed increased uptake, and five new lesions were established. Of the six patients, TUR in PT increased in two (one survived), decreased in one (exitus), was unchanged in two (two exitus) on post-TH scans, and PT totally disappeared in one (survived) patient. Conclusions Tc-99m (V) DMSA scans are useful in detecting LCL, except for those around the blood pool regions, making it a promising modality to monitor TH response. Obtaining a single fifth hour late Tc-99m (V) DMSA scan is appropriate. SPECT should be applied to all patients for the detection of deeply located lesions.     

Reduced Tc-99m DMSA uptake in a patient with renal tubular acidosis: effect of acid-base imbalance

Tc-99m dimercaptosuccinic acid (DMSA) is used as a renal cortical imaging agent to detect parenchymal abnormalities especially in children. Kidney uptake of DMSA provides an index for evaluation of a functional tubular mass, which depends on the renal blood flow and proximal tubular cell membrane transport function. We here report a boy with renal tubular acidosis, which has noticeably reduced uptake on his Tc-99m DMSA scintigraphy, despite a totally normal Tc-99m MAG-3 study. The case reported here clearly demonstrates a situation in which renal uptake of DMSA may be dissociated from a functional renal mass and the importance of acid-base balance which alters Tc-99m DMSA uptake.     

A case of recurrent cholangitis after bile duct injury during laparoscopic cholecystectomy: Value of scintigraphy with Tc-99m GSA and hepatobiliary scintigraphy for indication of lobectomy

A 39-year-old woman with acute cholecystitis and gallstones underwent laparoscopic cholecystectomy. She suffered from recurrent episodes of cholangitis due to injury of the major bile ducts during laparoscopic cholecystectomy. Hepatobiliary scintigraphy with Tc-99m Sn-N-pyridoxyl-5-methyltryptophan was performed. Although normal bile excretion was found from the left hepatic duct to the percutaneous transhepatic biliary drainage (PTBD) tube, excretion from the right hepatic lobe was prolonged. Scintigraphy with Tc-99m diethylenetriaminepentaacetic acid-galactosyl human serum albumin demonstrated atrophy of the right hepatic lobe and enlargement of the left hepatic lobe. Cholangiography via the PTBD tube revealed complete obstruction of the left hepatico-jejunal anastomosis and could not enhance the right intrahepatic bile duct. A right hepatic lobectomy was performed because of the atrophy, glissonitis and the absence of an appropriate bile duct for reconstruction. Postoperatively she was active and exhibited no evidence of recurrent cholangitis.     

A false positive I-131 MIBG due to dilated renal pelvis: a case report

A case of false positive I-131 MIBG imaging for detection of pheochromocytoma is presented. There was an area of increased tracer uptake in the left renal region that showed steadily reducing activity over a period of three days. This raised the suspicion of a dilated renal pelvis, which was later confirmed by Tc-99m DTPA imaging. It is advisable in cases of ambiguous I-131 MIBG imaging to use Tc-99m DTPA rather than Tc-99m DMSA for localizing the kidneys and renal pelvis.