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PubMedDate not supplied

The use of thallium-201 and technetium-99m subtraction scintigraphy for the localisation of parathyroid adenomas.

Parathyroid adenomas account for approximately 85% of cases of primary hyperparathyroidism. Several preoperative localisation techniques exist to aid the surgeon during neck exploration, with varying degrees of success. We report on the results of a modification of the established technique of thallium and technetium subtraction scintigraphy. The operative findings of 60 patients undergoing neck exploration for parathyroid adenoma were correlated with preoperative thallium and technetium subtraction scintigraphy scans. The radio-isotopes were administered in the reverse order to conventional administration, resulting in enhanced imaging. The adenomatous glands were correctly localised in all cases. The 100% sensitivity of this modified scanning technique supports a strategy of unilateral scan-directed neck exploration.

Adenoma↗

PubMed1997

Technetium-99m-tetrofosmin SPECT imaging of lung masses: a negative study.

UNLABELLED: Technetium-99m-tetrofosmin has emerged as a new radiopharmaceutical for myocardial imaging, in competition with 201Tl and 99mTc-MIBI. In this study, 99mTc-tetrofosmin was evaluated for its ability to detect malignant and benign lesions from single solid lung masses. METHODS: Forty-nine patients with a single solid lung mass based on chest radiograph findings received 99mTc-tetrofosmin SPECT of the chest to evaluate the value of 99mTc-tetrofosmin SPECT for detecting malignant and benign lesions. RESULTS: Only 61% of the lung malignancies were detected by 99mTc-tetrofosmin SPECT of the chest, including 53% of epidermoid carcinoma (ca), 67% of adeno ca, 75% of small-cell ca, 0% of undifferentiated large-cell ca and 100% of other lung malignancies. In addition, 50% of the benign lesions were detected by chest 99mTc-tetrofosmin SPECT. The probability of tetrofosmin uptake in the mass was not related to mass size. The diagnostic sensitivity, specificity and accuracy were 61%, 50% and 59%, respectively, for differentiating malignant and benign lesions when diagnosing a single solid lung mass. CONCLUSION: Technetium-99m-tetrofosmin SPECT of the chest is of little or no value for the detection of lung ca from single solid lung masses.

Adenocarcinoma↗

PubMed1997

Metabolism of technetium-99m-L,L-ethyl cysteinate dimer in rat and cynomolgus monkey tissue.

UNLABELLED: Technetium-99m-L,L-ethyl cysteinate dimer (99mTc-ECD) is thought to be hydrolyzed in the brain by an enzyme and to be trapped as a hydrophilic product. We investigated the characteristics of the enzymatic system that metabolizes 99mTc-ECD. METHODS: In 50 mM phosphate buffer (pH 7.4), 99mTc-ECD was incubated with various concentrations of homogenates of rat tissues (blood, liver and brain) or cynomolgus monkey tissues (blood, liver, cerebral gray matter, cerebral white matter and cerebellar gray matter), and the metabolic rates were assessed. Inhibition studies were performed using diisopropyl fluorophosphate, eserine and p-chloromercuribenzoate as inhibitors. The metabolic rates in the brain homogenates of rat and monkey were measured at various levels of pH, ranging from 6.6 to 7.6. Technetium-99m-L,L-ethyl cysteinate dimer metabolism was also examined in the presence of purified enzymes. RESULTS: In both species, the metabolic rate was high in liver tissue, intermediate in brain tissue and low in blood. The rate in cerebral gray matter of cynomolgus monkey was higher than those in rat brain, monkey cerebral white matter and monkey cerebellar gray matter. All substances used as inhibitors depressed 99mTc-ECD metabolism, and the response was different among tissues. Reduction in pH induced slight decreases in metabolic rate. Hydrophilic conversion of 99mTc-ECD was observed after incubation with porcine liver carboxylesterase. CONCLUSION: These results support the hypothesis that the hydrophilic conversion of 99mTc-ECD is mediated by enzymes. It is also suggested that various enzymes catalyze the hydrolysis of 99mTc-ECD and that the enzymatic system that metabolizes 99mTc-ECD is different between tissues and between species.

Acetylcholinesterase↗

PubMed1997

[Optimum protocol of technetium-99m tetrofosmin myocardial perfusion imaging for the detection of coronary stenosis lesions in Kawasaki disease].

The clinical usefulness of a new myocardial perfusion imaging agent, technetium-99m tetrofosmin, was assessed in 58 patients for a total of 76 times (mean age 9.7 years, 1-15 years) including 20 with and 26 without significant coronary stenotic lesions in Kawasaki disease. Pharmacological (dobutamine or adenosine triphosphate disodium) or exercise stress technetium-99m tetrofosmin single photon emission computed tomography was performed under stress and at rest on the same day. The sensitivity for detection of stress-induced perfusion defects by this method was 90% (18/ 20) and the specificity was 85% (22/26). The dose was 9.3 +/- 2.5 MBq/kg under stress and 18.7 +/- 5.6 MBq/kg at rest. No significant correlation was recognized between the dose and the image quality. Adequate image quality was provided by projection time 20-40 sec per frame. Increased liver accumulation was seen in 24% (18/76), especially in younger and pharmacological stress cases. The acquisition starting time after tetrofosmin injection was 58.4 +/- 18.7 min in the negative increased liver accumulation group and 43.7 +/- 18.3 min in the positive group (p < 0.01). We recommend that the following protocol is used for pediatric imaging. 1) The standard tetrofosmin dose is rougly 10 MBq/kg (upper limit 370 MBq) at stress and the double dose for the rest imaging. 2) SPECT projection time of 20-40 sec per frame. 3) In practice, the patient should be fasting prior to stress injection, and the imaging should be done 1 hour after eating. The rest injection should be done immediately thereafter, and the rest image should be obtained 1 hour later.

Adolescent↗

PubMed1998

Diagnostic accuracy of technetium-99m-pertechnetate scintigraphy with lemon juice stimulation to evaluate Warthin's tumor.

UNLABELLED: This study investigated the diagnostic accuracy of 99mTc-pertechnetate scintigraphy with lemon juice stimulation for evaluating parotid gland Warthin's tumor. METHODS: Technetium-99m-pertechnetate scintigraphy with intraoral lemon juice stimulation was used to evaluate a total of 68 parotid gland lesions clinically suspected of being Warthin's tumor in 62 patients. Twenty-three of the 68 lesions were subsequently histologically confirmed to be Warthin's tumor, whereas the remaining 45 lesions were histologically diagnosed as being other lesions. RESULTS: Technetium-99m-pertechnetate scintigraphy with lemon juice stimulation correctly diagnosed 18 of 23 Warthin's tumors as being Warthin's tumor but was unable to diagnose the other five Warthin's tumors. Further, scintigraphy correctly diagnosed 41 of 45 non-Warthin's tumors as being non-Warthin's tumor but misdiagnosed other four non-Warthin's tumors as Warthin's tumor. Thus, the sensitivity of scintigraphy for diagnosing Warthin's tumor was found to be 78%, its specificity 91% and its accuracy 87%. On the basis of prestimulation images alone, however, the sensitivity was estimated to be 65%, its specificity 93% and its accuracy 84%. CONCLUSION: For evaluating Warthin's tumor, the sensitivity of 99mTc-pertechnetate scintigraphy was relatively low, although the specificity was sufficiently high. Lemon juice stimulation improved the sensitivity markedly but decreased the specificity slightly. Thus, 99mTc-pertechnetate scintigraphy with lemon juice stimulation should be carefully performed for diagnosis of Warthin's tumor.

Adenolymphoma↗

PubMed1998

Technetium-99m labeled to human immunoglobulin G through the nicotinyl hydrazine derivative: a clinical study.

UNLABELLED: A novel method to label polyclonal human immunoglobulin G (IgG) with 99mTc through the nicotinyl hydrazine derivative (HYNIC) has shown promising results in the detection of experimental infection. In this study, 99mTc-labeled HYNIC-IgG was directly compared to (111)In-labeled diethylenetriaminepentaacetic acid (DTPA)-IgG in patients suspected of infectious or inflammatory disease. METHODS: Thirty-seven patients (22 women and 15 men; mean age = 54 yr, range = 17-78 yr) with 39 suspected infectious or inflammatory foci were prospectively studied. After administration of 740 MBq 99mTc-HYNIC-IgG, imaging was performed at 4 and 24 hr postinjection. To avoid cross-over activity, (111)In-DTPA-IgG was injected 24 hr after 99mTc-HYNIC-IgG and imaged at 4, 24 and 48 hr postinjection. The scintigraphic results were confirmed by microbiological, histological, radiological and clinical methods. RESULTS: Technetium-99m-HYNIC-IgG and (111)In-DTPA-IgG scintigraphy showed 100% concordancy. All 17 patients with proven infection or inflammation (19 foci, mainly localized in the locomotor system) had positive scintigraphic findings. No false-negative scintigrams were recorded. In three patients, the scintigrams were concordantly false-positive. As a result, the sensitivity and specificity of imaging infectious or inflammatory foci with 99mTc-HYNIC-IgG and (111)In-DTPA-IgG in these patients were 100% and 85%, respectively. CONCLUSION: Technetium-99m-HYNIC-IgG scintigraphy is equally as effective as (111)In-IgG scintigraphy for the detection of infection and inflammation. The apparent physical and logistic advantages of 99mTc over (111)In make 99mTc-HYNIC-IgG a promising new radiopharmaceutical for imaging infection and inflammation.

Bacterial Infections↗

PubMed1992

Scintigraphic evaluation of disease activity in rheumatoid arthritis: a comparison of technetium-99m human non-specific immunoglobulins, leucocytes and albumin nanocolloids.

Technetium-99m-labelled, non-specific, polyclonal, human immunoglobulin G (99mTc-hIG) has been used to quantify synovial inflammation in rheumatoid arthritis. A comparison was carried out between the scintigraphic results obtained with this tracer, 99mTc-hexamethylpropylene amine oxime-labelled white blood cells (99mTc-WBC) and 99mTc-albumin nanocolloids (99mTc-NC). Twenty patients affected by rheumatoid arthritis and suffering from clinically active synovitis were studied with 99mTc-hIG. The number and sites of the involved joints had been previously assessed on the basis of the presence of pain and/or swelling. A radiological examination had already been carried out on all the joints. Two days after the 99mTc-hIG scan, 10 patients (group 1) underwent 99mTc-WBC scintigraphy and the other 10 (group 2) underwent a 99mTc-NC scan. The results show that the results of 99mTc-hIG and 99mTc-NC scans are in agreement with clinical examinations in the majority of cases. However, a certain number of positive joint scans corresponding to negative clinical examinations was found. The numerical distribution of these results according to the radiological stages seems to show that 99mTc-hIG is more useful than 99mTc-NC in the initial phases of the disease. The 99mTc-WBC scan was negative in a consistent percentage of the joints previously assessed as clinically and 99mTc-hIG scan positive.

Arthritis, Rheumatoid↗

PubMed1983

The role of technetium-99m iminodiacetic acid (IDA) cholescintigraphy in acute acalculous cholecystitis.

Technetium-99m iminodiacetic acid (IDA) cholescintigraphy was performed in 15 patients with acute acalculous cholecystitis. Fourteen of the 15 patients with acute disease had positive findings, indicating the presence of cystic duct or common duct obstruction. One case in which the gallbladder was visualized failed to respond to sincalide stimulation; this was classified as a suggestive finding of disease. The diagnostic accuracy of 99mTc-IDA cholescintigraphy was far superior to the other imaging studies used (8 sonograms, 1 intravenous cholangiogram, 3 oral cholecystograms, 1 percutaneous transhepatic cholangiogram). The 99mTc-IDA study is recommended as the imaging procedure of choice for examining patients with suspected acute acalculous cholecystitis.

Acute Disease↗

PubMed1985

Disparate hepatic imaging with technetium-99m sulfur colloid and disofenin in Wilson's disease.

A 10-yr-old boy presented with fulminant hepatic failure. Technetium-99m sulfur colloid images showed absent reticuloendothelial function in the liver. A [99mTc]-disofenin hepatobiliary scan visualized liver parenchyma and biliary excretion. Disparate appearance of the liver may be seen in other hepatic diseases, but should be remembered as a possible pattern in Wilson's disease.

Child↗

PubMed1980

Tc-99m HMDP (hydroxymethylene diphosphonate): a radiopharmaceutical for skeletal and acute myocardial infarct imaging. II. Comparison of Tc-99m hydroxymethylene diphosphonate (HMDP) with other technetium-labeled bone-imaging agents in a canine model.

Technetium-99m hydroxymethylene diphosphate (Tc-HMDP) was compared with the two other diphosphonates (Tc-MDP and Tc-HEDP) and Tc-99m pyrophosphate (Tc-PPi) in a canine model of acute myocardial infarction. The TC-HMDP showed higher uptake in infarcted myocardium than the other two diphosphonates, and uptake equivalent to that of Tc-PPi.

Animals↗

PubMed1983

The technetium phosphate bone scan in the diagnosis of osteomyelitis in childhood.

We reviewed the technetium phosphate scans of 280 patients who had been referred with a clinical diagnosis of osteomyelitis in order to establish the diagnostic accuracy of this procedure. Strict criteria were established to define two subgroups: one of patients with proved osteomyelitis and one of patients who definitely did not have osteomyelitis. The scan correctly identified osteomyelitis at fifty-five of sixty-two sites, and was correctly negative in seventy-four of seventy-nine patients without osteomyelitis. The scan correctly distinguished all cases of cellulitis or soft-tissue abscess from osteomyelitis, but identified osteomyelitis in eight of thirty-nine patients with septic arthritis. The phosphate bone scan maintained this accuracy through any duration of symptoms, and performed almost equally well at all skeletal sites and in all age groups.

Abscess↗

PubMed1996

Comparative radionuclide imaging of metastatic insular carcinoma of the thyroid: value of technetium-99m-(V)DMSA.

We report a case of metastatic insular carcinoma of the thyroid evaluated with 201TI, 99mTc-MIBI, 99mTc-(V)DMSA, 99mTc-MDP and 131I whole-body scans, which were obtained after total thyroidectomy. For the majority of lesions detected in the skeleton and soft tissue, 131I images were generally available, although most were visualized easier with 99mTc-(V)DMSA. Technetium-99m-MDP images were considered better than 99mTc-(V)DMSA images in showing bone lesions but not soft-tissue lesions. Both 201TI and 99mTc-MIBI scans provided sufficient advantage to exhibit neck and mediastinal metastases, but they did not surpass 99mTc-(V)DMSA in detecting abdominal or bony lesions. In this patient with various metastases from insular carcinoma of the thyroid, 99mTc-(V)DMSA seemed to be the tracer of choice for whole-body imaging.

Bone Neoplasms↗

PubMed1984

Technetium-99m-labeled macroaggregated albumin arteriography for detection of abnormally positioned arterial catheters during infusion chemotherapy.

The arterial catheter position of 500 courses of intra-arterial chemotherapy were monitored by intraarterially introduced Technetium-99m macroaggregated albumin (MAA) particles. Seventeen instances of abnormally positioned catheters (3.4%) were detected by MAA arterial perfusion (MAAAP). All these abnormally positioned catheters were subsequently repositioned resulting in improved tumor perfusion. Plain radiographs obtained in eight instances failed to reveal the abnormally positioned catheter in four, while all eight of these abnormally positioned catheters were detected by MAAAP. Abnormally positioned catheters detected by MAAAP were either immediately after arterial catheter placement (nine instances) or during the course of chemotherapy (eight instances). Of the right instances of displaced catheters during intra-arterial chemotherapy, six instances were accompanied by clinical signs and symptoms suggestive of displaced catheter. Arteriovenous shunting was documented in 5 of 12 hepatic MAAAP studies as evidenced by increased lung activity. When the catheters were displaced in these cases, the lung activity changed: completely disappearing in two instances; decreasing in two instances and remaining unchanged in one.

Antineoplastic Agents↗

PubMed1997

Preoperative determination of the surgical procedure for hepatectomy using technetium-99m-galactosyl human serum albumin (99mTc-GSA) liver scintigraphy.

Technetium-99m-diethylenetriaminepentaacetic acidgalactosyl human serum albumin (Tc-GSA) is a new liver scintigraphy agent which binds to the asialoglycoprotein receptors. We evaluated the preoperative assessment for hepatectomy using Tc-GSA liver scintigraphy. Ninety patients with hepatocellular carcinoma were admitted for elective hepatectomy. Tc-GSA scintigraphy was conducted after the intravenous injection of Tc-GSA, and maximal removal rate of Tc-GSA (GSA-Rmax) was calculated using a radiopharmacokinetic model. Measurement of GSA-Rmax, conventional liver function, and 15-minute retention rate of indocyanine green (ICGR15) was carried out preoperatively. The relationships between liver functions, histological activity index (HAI), ICGR15, and GSA-Rmax values were estimated. A significant correlation was obtained between GSA-Rmax and ICGR15 (r = .534, P < .0001). Preoperative discrepancies between GSA-Rmax and ICGR15 values were seen in 15 patients. In these cases, the GSA-Rmax values correlated well with the total HAI scores (r = .595, P < .02), but no significant correlation was seen between the ICGR15 and HAI scores. Two patients died of postoperative liver failure within 2 months of the operation. These two patients were found to have severe discrepancies between their preoperative GSA-Rmax and ICGR15 values. We concluded that GSA-Rmax might be useful for selecting candidates for hepatectomy and that extended hepatectomies (di- and tri-segmentectomy) are high-risk surgical procedures in the case of low GSA-Rmax scores (below 0.35).

Adult↗

PubMed1992

Using technetium-99m (V) dimercaptosuccinic acid to detect malignancies from single solid masses in the lungs.

Fifty patients (43 male, 7 female, age 31-77 years) with single solid masses in their lungs based on the findings of a chest X-radiograph [40 malignancies: 5 small cell carcinoma (Ca), 17 epidermoid Ca, 12 adeno Ca, 6 undifferentiated large cell Ca] and 10 benign lesions underwent technetium-99m (V) dimercaptosuccinic acid [99m-(V)DMSA] scans to evaluate the usefulness of 99mTc-(V)DMSA in the detection of lung Ca with different cell types and benign lesions. Only 43% (17/40) of the malignancies in the lungs were detected by 99mTc-(V)DMSA, including 29% (5/17) epidermoid Ca, 50% (6/12) adeno Ca and 17% (1/6) undifferentiated large cell Ca of the lungs. However, all 5 cases of small cell Ca and 11 cases combined with bone metastasis were revealed by 99mTc-(V)DMSA. In addition, 3 of the 10 benign lesions (2 organizing pneumonias, 1 benign tumor) presented with an uptake of 99mTc-(V)DMSA. The diagnostic sensitivity, specificity and accuracy were 43%, 70% and 48%, respectively, in differentiating malignant from benign lesions for the single solid mass in the lungs. In conclusion, 99mTc-(V)DMSA is of little or no use in the differentiation of lung Ca from single solid masses in the lungs.

Adenocarcinoma↗

PubMed1993

Evaluation of white cell scintigraphy using indium-111 and technetium-99m labelled leucocytes.

Indium-111 oxine labelled leucocyte (111In oxine leucocyte) scintigraphy is the test of choice in detecting occult infection and localising focal inflammation. 111In oxine labelling is technically difficult and expensive and leucocyte labelling with technetium-99m stannous colloid (99mTc Sn colloid) has been considered to be an alternative. Leucocytes from 40 cases referred for investigation of occult infection or localisation of inflammation were simultaneously labelled with 111In oxine and 99mTc Sn colloid with dual isotope acquisition performed at 1, 3 and 24 h. Twenty-four hour 99mTc Sn colloid scans were corrected for 111In downscatter. Each case was independently interpreted by two experienced observers. Twenty-one patients demonstrated positive 111In oxine leucocyte scans. Using 111In oxine leucocyte scans as the gold standard, 99mTc Sn colloid leucocyte scanning had an overall sensitivity of 86% and a specificity of 95%. Clinical follow-up verified that three patients had false negative 99mTc Sn colloid leucocyte scans and one patient had a false positive. Further clinical evaluation of 99mTc Sn colloid labelled leucocytes is required before they can become a reliable replacement for 111In oxine leucocytes.

Colloids↗

PubMed1992

Uterine technetium-99m mercaptoacetyltriglycine and diethylene triamine penta-acetic acid uptake in the scintigraphic evaluation of transplanted kidneys.

An anuric 35-year-old woman with a renal transplant underwent serial renal scintigraphy studies to screen the kidney function. A hypervascular pelvic mass in the region of the bladder was identified during technetium-99m mercaptoacetyltriglycine (MAG3) and also during 99mTc diethylene triamine penta-acetic acid (DT-PA) scintigraphy. She was in the secretory phase of the uterine cycle during the study and had no gynaecological problem to explain the radioactivity accumulation. The accumulation of 99mTc-MAG3 mimicking the bladder was considered as uterine activity. To our knowledge, this is the first case of uterine visualization with 99mTc-MAG3.

Adult↗

PubMed1992

Technetium-99m diethylene triamine penta-acetic acid and dimercaptosuccinic acid in the detection of a segmental branch stenosis of the renal artery by captopril renography.

We present a case in which a 39-year-old woman with correctable bilateral renovascular hypertension did not show abnormality during post-captopril technetium-99m dimercaptosuccinic acid (DMSA) study. Post-captopril 99mTc-diethylene triamine penta-acetic acid (DTPA) scintigraphy revealed the adverse effect of a stenosis of the artery supplying the upper part of her left kidney but failed to uncover the existence of severe multiple narrowings of the right renal artery. After bilateral renovascular reconstructive surgery, the hypertension completely disappeared. This case illustrates that DTPA may be more efficacious than DMSA in the detection of segmental loss of renal function induced by angiotensin converting enzyme inhibition.

Adult↗