Search

In this study, we examined the usefulness of whole body coronal images and whole body cine display MIP images (CMIP) upon which image processing was carried out after whole body SPECT in comparison to the usefulness of whole body images (WB/SC) compensated by scattered radiation in tumor/inflammation scintigraphy with 67Ga-citrate (67Ga). Image interpretation was performed for the 120 patients with confirmed diagnoses, and the accuracy of their diagnoses was studied by three nuclear medical physicians and two clinical radiological technologists by means of sensitivity, specificity and ROC analysis. The resultant data show that sensitivity, specificity, accuracy and the area under the ROC curve Az in the WB/SC were approximately 65%, 86%, 74% and 0.724, respectively, whereas sensitivity, specificity, accuracy and Az of the image reading system in which CMIP is combined with whole body coronal images reconstructed by the OS-EM method were approximately 93%, 95%, 94% and 0.860, respectively. Furthermore, coronal images reconstructed by the OS-EM method tended to be superior to those produced by the FBP method in both diagnostic accuracy and ROC analysis. In conclusion, the image reading system in which CMIP is combined with whole body coronal images reconstructed by the OS-EM method was shown to be superior in diagnostic accuracy and ROC analysis. Our data suggest that whole body SPECT is an excellent technique as an alternative to WB/SC.

Unlabelled: This study was performed to assess the relationship between 201Tl chloride uptake and brain tumor proliferation using monoclonal antibody Ki-67 and proliferating cell nuclear antigen (PCNA)., Methods: Thirty-four patients with brain tumors were studied. Serial SPECT images were recorded and thallium uptake (Tl index) and washout rates in the tumors were calculated. Imaging results were compared with those from biopsy and histology. Cell proliferation was determined by PCNA or Ki-67 monoclonal antibody staining., Results: Thallium-201-chloride indices of the astrocytoma were 1.73 +/- 0.17 and 1.48 +/- 0.07 on early and delayed images, respectively. On the other hand, 201TI indices for anaplastic astrocytoma were 2.60 +/- 1.05 and 1.76 +/- 0.93 and 3.26 +/- 1.63 and 2.23 +/- 0.56 for glioblastoma. The correlation between the 201TI (delay) and Ki-67 indices for astrocytic tumor. There were no significant differences between Ki-67/PCNA indices and washout rates., Conclusion: There was a positive correlation between PCNA but not the Ki-67 labeling index and the 201Tl index. With the use of a noninvasive technique, 201TI index supports the PCNA index.

Six patients with cardiomyopathy were imaged following intravenous injection of an indium-111 labeled monoclonal antibody directed against the heavy chain of cardiac myosin. Two patients had hypertrophic non-obstructive cardiomyopathy (HNCM), two patients had dilated cardiomyopathy (DCM), and two patients had specific heart muscle disease. One of 2 patients with HNCM and one of 2 patients with DCM had a positive antimyosin scan. The 2 patients with specific heart muscle disease manifested persistent blood pool activity of the antibody, thereby precluding interpretation of the images. The present report demonstrates that antimyosin antibody imaging may provide evidence of myocardial injury, or necrosis in some patients with cardiomyopathy.

The recent expansion of interventional cardiovascular techniques has stimulated the development of non-invasive cardiac studies, to evaluate the outcome of the interventional therapy. Radionuclide ventriculographic technique provides to quantify global left ventricular systolic/diastolic performance, and evaluate the regional left ventricular wall motion during rest or exercise. This concept was extended from the "bedside" to the ambulatory environment with the description of a battery powered device, the radionuclide ventricular function monitor. To assess the performance of cardiac function using radionuclide ventriculography to that using the ambulatory ventricular function monitor, the systolic and diastolic function were measured at rest in a series of healthy volunteers (n = 10) and in patients with cardiovascular disease (n = 23). Seventeen patients had coronary artery disease (CAD) with prior myocardial infarction, three patients had coronary artery disease, and three patients had dilated cardiomyopathy. The 23 patients manifested a wide variation in LV systolic function. The relationship between the multiple gated acquisition (MUGA)-ejection fraction and the ambulatory ventricular function monitor-ejection fraction correlated well (r = 0.90). As a complement to the radionuclide perfusion studies, cardiac blood pool imaging and radionuclide ventricular function monitoring allow for through non-invasive description of cardiac physiology and function in patients with various cardiac disorders.

To evaluate the primary site, pulmonary hilar, and mediastinal lesions in patients with lung cancer, thallium-201 using single-photon emission computed tomography (SPECT) was used as a tumor agent. The study population consisted of 7 patients (5 men and 2 women), aged 57 to 82 years (mean 68). Tl-201 tomography imaged positive at the primary site in all patients with lung cancer. The images demonstrated the tumor and/or mediastinal lymph nodes that were greater than 2.0cm. In particular, each tomograms facilitated the identification of the Tl-201 increased uptake in proportion to primary site. The short waiting period after injection with Tl-201 clearly offers a major advantage over alternative tumor imaging agents, such as Ga-67 or radiolabeled monoclonal antibodies. Furthermore, Tl-201 SPECT may be useful to detect the tumor and/or mediastinal lymph nodes in patients with lung cancer.

To evaluate the therapeutic effects of percutaneous nephroureterolithotomy, the renal function of eleven patients with renal calculi was studied, pre- and post-intervention. Renal function was determined, by renal scintigraphy with the renal agent, Tc-99m diethylenetriaminepentaacetic acid (DTPA). In each renal scintigram the renogram curve was analyzed and the following were determined by deconvolution analysis; the renal fraction of blood flow (RFBF), DTPA-glomerular filtration ratio (GFR), and the renal mean transit time (MTT). The successful results in percutaneous nephroureterolithotomy (PNL) was proven using the radionuclide technique in most cases. From these results it can be concluded that renal scintigraphy is an effective procedure to evaluate the effect of PNL for treating renal calculi and secondary hydronephrosis.

In a DAB-hepatoma organic tumor, Ga-67 accumulated markedly in the hepatocellular carcinoma with scant stroma but not in the cholangioma that was rich in connective tissue. No granulation tissue was formed around the tumor. In transplanted tumors (Ehrlich's tumor and Sarcoma 180), Ga-67 accumulated in the granulation tissue within the fibroblasts, leukocytes and capillaries surrounding the tumor, rather than in the tumor. In inflammatory lesions, Ga-67 uptake was similar in granulation tissue with large numbers of phagocytes, such as leukocytes and histiocytes, and capillaries. There was a very good correlation between the degree of Ga-67 uptake and of cellular infiltration and the proliferation of capillaries. Ga-67 uptake, both in inflammatory lesions and in transplanted tumors, was observed in the granulation tissue. This result implies that the mechanisms of Ga-67 uptake in tumor and inflammatory tissues are not the same, because Ga-67 accumulated in the DAB-hepatoma that had no inflammatory granulation tissue. This study indicates that a non-transplanted tumor is required to study Ga-67 accumulation in tumors, as different results may occur in tumors with and without inflammatory granulation tissue.

The distribution of 67Ga-citrate in the hepatoma of rat induced by 3'-methyl-4-dimethylaminoazobenzene was studied. 67Ga uptake ratio resected specimen, autoradiography and histological specimen were compared each other. 67Ga uptake ratio of the tumor was increased 1.6 to 7.2 times (average 4.4) to control group. Regardless of the size of the tumor, macroautoradiographically observed distribution of 67Ga-citrate in the hepatoma was higher in the peripheral zone than in the central zone. Histologically the degeneration of tumor cell was low or absent in the peripheral zone of tumor, whereas it was intense in the central zone. 67Ga-citrate was highly accumulated in the zone which the degeneration was low or absent. We, however, could not demonstrate the site where 67Ga-citrate was incorporated.

The heart-to-liver (H/L) uptake ratio in rats was determined 8 min after the rectal administration of 201Tl. Apart from normal controls, three groups of rats were examined; these were composed of animals with induced (1) acute hepatic damage, (2) liver cirrhosis, and (3) partial portal-vein ligation. After the rectal administration of 201Tl, 51Cr-labeled microspheres were injected into the spleen. The radioactivity of the removed liver, lungs, and heart was determined in a gamma-well scintillation counter, and the radioactivity of 201Tl and the 51Cr-labeled microspheres was separately calculated using simultaneous equations derived from the results of a preliminary experiment. The H/L ratios (201Tl) in the normal controls and the animals with acute hepatic damage were not significantly different; however, there was a positive correlation (P less than 0.01) between the H/L ratio and the shunt index (51Cr microspheres) in three groups, i.e., normal controls, liver cirrhosis, and partial portal-vein ligation.

The renal circulation of patients with essential hypertension and renovascular hypertension was evaluated using 99mTc-DTPA. The first renal peak count (the first Cmax; FCmax), time phase distribution (the first Tmax; FTmax), and blood velocity (the FCmax/FTmax) were calculated by digital imaging. This yields a visual image of the renal circulation. We consider that the increase in the renal first pass blood flow in patients with essential hypertension is best observed pixel by pixel. The FCmax and FCmax/FTmax images before and after treatment by percutaneous transluminal renal angioplasty in patients with renovascular hypertension clearly show its therapeutic effect. The FI technique, therefore, has the advantage that it can be performed at the same time as the conventional routine examinations of renal function. This makes it very useful clinically.