Technetium-99m Glucoheptonate Research Articles

Evaluation of Technetium-99m glucoheptonate single photon emission computed tomography for brain tumor grading.

Background:This study is designed to appraise the diagnostic value of technetium-99m glucoheptonate (Tc-99m GHA) single photon emission computed tomography (SPECT) in brain tumor grading.Subjects and Methods:The study was performed on 30 patients referred from the Department of Neurosurgery, who were from both urban and rural areas. Data were collected through interview, history taking, and clinical examination followed by recording the desired parameters and finally imaging. The study subjects were divided into five groups: Controls (n = 4), low-grade tumors (n = 8), high-grade tumors (n = 8), metastases (n = 5), and nonneoplastic lesions (n = 5). This division was based on the World Health Organization (WHO) classification postclinico-histological diagnosis. Each of the subjects underwent contrast-enhanced computed tomography/contrast-enhanced magnetic resonance and Tc-99m GHA SPECT preoperatively. All were followed up postoperatively, and histopathological reports were regarded as the gold standard for tumor grading wherever available.Results:It was found that high-grade tumors (Grades III/IV and IV/IV according to the WHO classification) showed significantly higher tumor to normal (T/N) ratios as well as Tmax/N ratios when compared with low-grade tumors (Grades I/IV and II/IV), metastases or nonneoplastic lesions.Conclusions:In summary, the results of this study suggest that in situations where a preoperative grading of tumor is required Tc-99m GHA can be used in tumor grading and its use should be encouraged. Semi-quantitative analysis using both T/N as well as Tmax/N can be used in differentiating high-grade tumors from low-grade ones.

Quantification of ocular inflammation with technetium-99m glucoheptonate

Histological and morphometric evaluation of ocular inflammation is difficult, particularly when there is extensive ocular involvement with abscess formation and necrosis. A quantitative imaging procedure applicable to humans would be important clinically. To establish such a procedure, turpentine-induced ocular inflammation was obtained by subconjunctival injection in the right eye of 55 rabbits. The left eye was used as control and injected with a volume of saline equal to the volume of turpentine in the right eye. Volumes of turpentine or saline were 0.02, 0.04, 0.06, 0.2 and 0.6 ml, and the rabbits were divided into groups 1-5, according to these volumes. Imaging was performed 48 h after turpentine injection and 6 h after intravenous injection of 10 mCi of technetium-99m glucoheptonate (99mTc-GH). An inflammatory reaction index (IRI), defined as the ratio of counts of the right eye divided by counts of the left eye, was used. IRIs were proportional to the degree of inflammation and allowed the distinction of 3 subgroups: one represented by group 4, one by group 5 and one by groups 1, 2 and 3. This method of quantification of ocular inflammatory processes using 99mTc-GH is original, rapid, non-invasive, reproducible and safe, although unable to differentiate inflammatory processes caused by doses of turpentine which are very small and close to each other. It is conceivable that its application to humans will bring new insight into the ocular inflammatory process and response to therapy.

A practical SPECT technique for quantitation of drug delivery to human tumors and organ absorbed radiation dose

A practical quantitative single photon emission computed tomographic (SPECT) technique based on an empirical threshold analysis permits accurate measurements in humans of drug delivery and absorbed radiation dose. The limits of the method have been explored using a wide range of phantom volumes, concentrations, and target-to-nontarget ratios. A threshold of 43% was found to give the best results using volumes of 30 to 3,800 cc. An excellent correlation (r = .99 with a standard error of estimate [SEE] of 41 cc) was found between SPECT measured volumes and actual phantom volumes. A similarly high correlation (r = .98, SEE = 260 counts/voxel) was found in 77 measurements of concentrations between 0.01 and 3.6 microCi/cc. There was a direct relationship between the target-to-nontarget ratio of phantoms and the accuracy of volume measurements. The technique has been validated by an excellent in vivo/in vitro correlation of uptake in human tumors. The tumor cumulative concentration and tumor-to-blood ratio were used for assessment of drug delivery. In vivo quantitative measurements of the pharmacokinetics of technetium-99m (99mTc) glucoheptonate, cobalt-57 (57Co) bleomycin and platinum-195m (195mPt) cisplatin in human tumors in vivo indicates that, in contrast with tumor models in animals, there is a marked variability in drug delivery even in tumors with the same histology. Future development of labeled drugs should make it possible to use quantitative SPECT for predicting tumor response to therapy and for tailoring chemotherapy for the individual patient under treatment. SPECT quantitation of organ concentration was used for Medical Internal Radiation Dose committee (MIRD) calculations of organ absorbed radiation dose from 99mTc-labeled RBCs. Excellent in vivo/in vitro correlations were obtained between SPECT measured concentrations of blood radioactivity in the heart and in vitro measurements of blood samples. The possibilities and limitations of this technique are discussed and its use for in vivo measurement in humans of absorbed radiation dose from radiopharmaceuticals is suggested.

The role of scintigraphy in urinary tract infection

There is controversy regarding the role of radiological imaging for urinary tract infection (UTI). The "gold standard" has been the intravenous pyelogram (IVP). Yet, the IVP has a very limited value with only about 25% of children with pyelonephritis demonstrating abnormalities. Ultrasound (US) has recently been advocated as a replacement for the poorly sensitive and poorly specific IVP. However, comparative studies between US and IVP indicate only an equivalent sensitivity and specificity. Cortical scintigraphy with Technetium-99m glucoheptonate (99mTc GH) or 99mTc dimercaptosuccinic acid (99mTc DMSA) has also been advocated as a means of differentiating parenchymal (pyelonephritis) from nonparenchymal (lower UTI) involvement in UTI. The clinical presentation may be misleading especially in the infant and child in whom an elevated temperature, flank pain, shaking chills, or an elevated sedimentation rate are often lacking. The clinician attempts to localize the site of infection for it has a direct bearing upon the therapy. A collecting system infection can often be eradicated with a single oral dose of an appropriate antibiotic, whereas renal parenchymal involvement requires IV therapy for an extended interval. Cortical scintigraphy can localize the site of infection with a high degree of accuracy. Recent studies report a sensitivity of 86% and specificity of 81% of pyelonephritis. This is in contrast to the IVP with a sensitivity of only 24% and US with a sensitivity of only 42%. The scintigraphic appearance of parenchymal infection of the kidney is a spectrum of minimal to gross defects reflecting the degree of histologic involvement that spans from a mild infection to frank abscess. Cortical scintigraphy can be used to monitor the evolution of scarring following infection. Cortical scintigraphy with 99mTc DMSA or 99mTc GH is the method of choice for the initial evaluation of UTI. Not only does it have a very high sensitivity and specificity for differentiating parenchymal from collecting system disease, but it also provides an accurate quantitative measurement of function and in combination with radioiodinated orthoiodohippurate renography and Lasix (furosemide; Abbott Laboratories, North Chicago) diuresis will also differentiate significant obstruction from stasis. The use of radionuclide techniques opens new vistas for the investigation of UTI. Cortical scintigraphy should become the gold standard by which other technologies, therapy, and theoretical considerations of pyelonephritis are measured.

Technetium-99m-glucoheptonatelung imaging; has it a role in the diagnosis of bronchial carcinoma?

It has been shown by Vorne et al. and Passamonte et al. that technetium-99m-glucoheptonate (Tc-GH) concentrates in bronchial carcinomas. The two studies reported similar sensitivities (88 and 91%, respectively) but discordant specificities (88 and 10%, respectively). In order to assess the uptake of Tc-GH in bronchial carcinomas we performed lung imaging on patients with an abnormal chest radiograph who were undergoing routine investigations for bronchial carcinoma. 108 patients (85 carcinoma, 23 non-carcinoma) were given 555 MBq (15 mCi) Tc-GH intravenously and scanned 5 h later. Images were assessed by one investigator (J.A.L.) without knowledge of the patient's clinical details or other results. Localized uptake of Tc-GH was seen in 71 out of 85 patients who proved to have bronchial carcinoma. Uptake was also seen in 16 out of 23 patients with a variety of non-malignant lung conditions. Sensitivity for bronchial carcinoma was 84%, and specificity 30%. Uptake did not vary significantly with histology. Eleven out of 12 patients with proven tuberculosis had increased uptake of Tc-GH; two of those patients also had inactive lesions which did not concentrate the tracer. In conclusion, Tc-GH is of limited value in the diagnosis of bronchial carcinoma, because of its low specificity. A possible role in the diagnosis of active tuberculosis may exist, following further assessment.

The value of obtaining renal images following brain scintigraphy with technetium-99m glucoheptonate.

The value of adding an extra view of the kidneys immediately following brain imaging with Tc-99m glucoheptonate was investigated in a two-year retrospective study at our institution. Between October 1982 and October 1984, 561 individuals underwent Tc-99m glucoheptonate brain imaging with the added renal view. Twenty-nine of these individuals (5.2%) demonstrated renal abnormalities. The abnormal renal findings were clinically correlated in 24 of these persons. Sixteen (67%) of these 24 individuals were unaware of any renal abnormality. Useful information can be obtained from renal images incidental to brain imaging at no added expense or radiation exposure to the patient, and at a minimal cost in time to the imaging clinic.

Glucoheptonate Measurement of Differential Renal Function

In previous studies using dogs whose renal function was rendered asymmetric by unilateral infarction or partial ureteral obstruction, the efficacy of technetium-99m diethylenetriamine pentaacetic acid and dimercaptosuccinic acid in the measurement of differential renal function was demonstrated. The present study was undertaken to determine if technetium-99m glucoheptonate could also be used to quantitate differential renal function in these conditions. Five dogs with partial ureteral obstruction, 4 with segmental infarction and 2 with ipsilateral combination of both were studied. Seven to 10 days following these interventions the animals were given a bolus injection of 10mCi Tc-99m glucoheptonate. This was acquired in the posterior projection on a minicomputer at 2 seconds/frame for 3 minutes. Static images were obtained anteriorly and posteriorly between 3 and 5 hours postinjection. The following day iothalamate and creatinine clearances were measured by ureteral catheterization. There was good correlation between differential function calculated from the 1 to 3 minute portion of the bolus study and that determined by the ureteral catheter studies, r > 0.99. Correlations based on the static images were less satisfactory due to pelvic retention in the obstructed animals, r = 0.73. We conclude that technetium-99m glucoheptonate may be used to determine differential renal function.

Bronchoalveolar Lavage and Technetium-99m Glucoheptonate Imaging in Chronic Eosinophilic Pneumonia

A patient with chronic eosinophilic pneumonia was evaluated using bronchoalveolar lavage, technetium-99m glucoheptonate, and transbronchial lung biopsy. Bronchoalveolar lavage revealed 43 percent eosinophils and correlated well with results of transbronchial lung biopsy. Technetium-99m glucoheptonate lung imaging demonstrated intense parenchymal uptake. After eight weeks of corticosteroid therapy, the bronchoalveolar lavage eosinophil population and the technetium-99m glucoheptonate uptake had returned to normal. We suggest that bronchoalveolar lavage, with transbronchial lung biopsy, is a less invasive way than open lung biopsy to diagnose chronic eosinophilic pneumonia. The mechanism of uptake of technetium-99m glucoheptonate in this disorder remains to be defined.

Nuclear Renal Imaging in Acute Pyelonephritis.

Patients with acute pyelonephritis may present with a spectrum of clinical signs and symptoms. There are few noninvasive diagnostic studies, however, to confirm or exclude this diagnosis. A small number of patients, generally those with severe disease, will demonstrate radiographic changes on excretory urography, but the lack of sensitivity of the IVP in early, acute pyelonephritis is well documented. Several radionuclide techniques have been proposed to assist in the earlier detection of this clinical problem including imaging with Mercury-197 chlormerodrin, Gallium-67 citrate, Technetium-99m glucoheptonate. Technetium-99m DMSA, and, more recently, Indium-111 labeled white blood cells. The success of the renal cortical imaging agents as well as those which localize in infection are described in this report. There appears to be a complimentary role or the cortical imaging agents and the radiopharmaceuticals which localize in bacterial infection. Cortical agents offer the advantage of specific assessment of functioning renal tissue and a convenient, rapid method for following the response to treatment in a noninvasive manner. A pattern is described which may be diagnostic; correlation with Gallium-67 citrate of Indium-111 WBCs may increase the probability of infection as the cause for the cortical abnormality. The measurement of differential renal function using cortical agents provides additional information to assist the clinician in predicting the late effects of infection. Improved sensitivity and specificity, and a reproducible method for following the response to therapy in patients with acute pyelonephritis are the advantages of the techniques described.

Nuclear renal imaging in acute pyelonephritis

Patients with acute pyelonephritis may present with a spectrum of clinical signs and symptoms. There are few noninvasive diagnostic studies, however, to confirm or exclude this diagnosis. A small number of patients, generally those with severe disease, will demonstrate radiographic changes on excretory urography, but the lack of sensitivity of the IVP in early, acute pyelonephritis is well documented. Several radionuclide techniques have been proposed to assist in the earlier detection of this clinical problem including imaging with Mercury-197 chlormerodrin, Gallium-67 citrate, Technetium-99m glucoheptonate. Technetium-99m DMSA, and, more recently, Indium-111 labeled white blood cells. The success of the renal cortical imaging agents as well as those which localize in infection are described in this report. There appears to be a complimentary role or the cortical imaging agents and the radiopharmaceuticals which localize in bacterial infection. Cortical agents offer the advantage of specific assessment of functioning renal tissue and a convenient, rapid method for following the response to treatment in a noninvasive manner. A pattern is described which may be diagnostic; correlation with Gallium-67 citrate of Indium-111 WBCs may increase the probability of infection as the cause for the cortical abnormality. The measurement of differential renal function using cortical agents provides additional information to assist the clinician in predicting the late effects of infection. Improved sensitivity and specificity, and a reproducible method for following the response to therapy in patients with acute pyelonephritis are the advantages of the techniques described.

Technetium-99m glucoheptonate renal scan in diagnosis of acute renal injury

Twenty-four patients with suspected renal injury were evaluated using high-dose intravenous pyelography, technetium-99m glucoheptonate radionuclide studies (RNS), and selective renal arteriography. Critical examination of these three diagnostic modalities reveal that RNS are extremely accurate in renal trauma evaluation and are more sensitive than intravenous pyelography. When RNS are used in conjunction with high-dose intravenous pyelography in the initial workup for renal trauma, 60 to 65 per cent of diagnostic angiograms may be avoided.

Early quantification of experimental myocardial infarction with technetium-99m glucoheptonate: Scintigraphic and anatomic studies

Recent advances in understanding of the pathophyslology of myocardial necrosis indicate the need for a noninvaslve method that will allow detection and quantification of infarcts in the first few hours after the onset of infarction. Myocardial infarct scintigraphy using technetium-99m glucoheptonate is capable of detecting infarction in dogs and man within 4 to 6 hours of onset. Studies were performed in 45 dogs with acute myocardial iniarction: 28 with an anterior infarct, 5 with an inferior infarct, 6 with an anterior infarct studied after infusion of mannttol and 6 with II-gatlon of the left anterior descending coronary artery and repertuslon of the ischemic area. The dogs were given 20 mCI of technetium-99m glucoheptonate 1 hour after coronary occlusion, subjected to imaging 5 to 9 hours later and then killed. The experiments revealed that (1) scintigraphic infarct size correlated with infarct weight for anterior ( r = 0.85) and inferior ( r = 0.88) infarcts; (2) technetium-99m glucoheptonate also concentrated in a rim of myocardium around the infarct that probably represented the ischemie zone; and (3) technetium-99m glucoheptonate uptake by infarcted myocardium could be greatly increased with mannltol and reperfusion.