[Pulmonary perfusion and ventilation scintigraphies before and after cardiac catheterization in infants with congenital heart diseases]

We performed 99mTc-MAA pulmonary perfusion scintigraphies before and after catheterization of 50 infants with congenital heart disease. 81mKr ventilation scintigraphies were also performed in 41 patients. Both right and left heart catheterization (23 patients) and right heart catheterization (27 patients) were performed by Seldinger's method. Pulmonary perfusion scintigraphies showed new perfusion defects in 6 patients (12%) following catheterization. Of six patients, three had ventilation defects. Clinical characteristics, duration of catheterization, hemodynamic variables were not significantly different between patients with and without lung perfusion defects. The lung perfusion defects seemed to be due to pulmonary embolism following cardiac catheterization.

Gallium-67 uptake in fibrous dysplasia of the bone

In a 43-year-old woman with fibrous dysplasia of the ribs and facial bone and in a 40-year-old man with fibrous dysplasia of the facial bone, there were considerable increases in the uptake of Tc-99m methylenediphosphonate (Tc-99m MDP) and Gallium-67 citrate. Fibrous dysplasia should be added to differential diagnosis of high Gallium-67 citrate uptake in the bone lesions.

[67Ga-citrate scintigraphy in patients with fever of unknown origin]

67Ga scintigraphy was performed in 49 patients with fever of unknown origin (FUO). Positive findings were observed in 25 patients out of 49 (51%). Occult focal lesions were demonstrated in 4 patients and useful information for the diagnosis was provided in 4 patients. In short, the examination showed diagnostic usefulness in 8 (32%) out of positive cases. 67Ga scintigraphy may be recommended as a further examination for patients with strongly suspected focal lesion in FUO.

[The evaluation of the bone marrow accumulation of Ga-67 citrate]

The bone marrow distribution of Ga-67 citrate may be influenced by various elements in serum. In order to make these points clear, 1,955 whole body images were reviewed on the relationship between the accumulation of bone marrow and laboratory examination data of each patients. Increasing accumulation in the bone marrow was determined as positive when the bones of lower extremities were deposited on the images, because these bones was not visualized in normal gallium image. Laboratory data of 20 patients without having bone marrow accumulation was used as control. The positive findings of bone marrow accumulation was observed in 38 patients (2%) including 23 malignancies and 15 benign disease. The malignant tumor infiltration to the bone marrow was demonstrated by bone marrow aspiration biopsy in 2 out of 7 patients with bone marrow accumulation of Ga-67. Seven out of 15 patients with benign disease were collagen disease such as aortitis syndrome or SLE. The values of hemoglobin, hematocrit, serum iron and creatinine clearance were significantly lower in the patients with positive findings in comparison with control. These results suggest that the lower level of serum iron and anemia may cause increasing bone marrow accumulation of Ga-67 citrate.

Tl-201 myocardial SPECT in patients with Duchenne's muscular dystrophy: a long-term follow-up

Tl-201 SPECT was used to evaluate myocardial involvement in 13 patients with Duchenne's muscular dystrophy. Serial studies of 9 patients were done at two-year intervals. The hypoperfused areas of the left ventricle became more prominent with age and severity.

[Cerebral blood flow imaging in patients with moyamoya disease]

The usefulness of IMP-SPECT and rCBF image by 133Xe inhalation method on rCBF in patients with moyamoya disease was studied. Six patients with moyamoya disease were diagnosed by cerebral angiogram, and STA-MCA anastomosis technique and EMS were done to reconstruct the rCBF. Low perfusion areas were detected around the cerebral infarction and hemorrhage and that of anterior and middle cerebral arteries by IMP-SPECT and 133Xe-rCBF image met by X-ray CT. After surgery, 4 out of 6 cases showed the improvement of rCBF by IMP-SPECT and 133Xe-rCBF image, as for clinical symptoms, there were reduction of TIA in 3 cases, and no rehemorrhage in 3 cases. In summary IMP-SPECT and 133Xe-rCBF image may be useful method to evaluate the rCBF in moyamoya disease and the change of rCBF post STA-MCA anastomosis technique and EMS.

Hepatic carcinosarcoma demonstrated by Ga-67 scintigraphy

A case of a primary hepatic carcinosarcoma, a very uncommon liver tumor in adults, demonstrated by Ga-67 scintigraphy, was reported. The liver image showed a lesion of low activity in the left lobe of the liver, whereas the Ga-67 image showed a moderate accumulation in the lesion detected by the liver scan and further indicated a high accumulation extending downwards from the hepatic lesion. An autopsy revealed that the huge abdominal tumor was composed of hepatocellular carcinoma and malignant mesenchymoma in the left hepatic lobe and in the lower part of the tumor, respectively. The Ga-67 image demonstrated these two different histological components of the tumor.

Dynamic SPECT with technetium-99m HM-PAO in meningiomas--a comparison with iodine-123 IMP

Technetium-99m hexamethylpropyleneamine oxime ([99mTc]HM-PAO) has recently been introduced as an alternative to N-isopropyl-p-[123I]iodoamphetamine ([123I]IMP) for measurement of regional cerebral blood flow. This study compares dynamic SPECT studies using the two tracers in seven patients with meningiomas. Regions of interest were placed over the lesion and contralateral homologous presumed normal area. The counting-rate ratio for the lesion to the contralateral homologous area (L/N ratio) was then calculated in the first image. L/N ratios of [99mTc]HM-PAO single photon emission computed tomography (SPECT) were lower than those of [123I])IMP SPECT, particularly in hypervascular meningiomas. Furthermore, time-activity curves showed that the washout of [99mTc]HM-PAO in the tumors was very slow or incomplete, preventing an accurate assessment of vascularity of meningiomas with [99mTc]HM-PAO, as is generally possible with [123I]IMP.

[Clinical cerebral perfusion scintigraphy with 123I-IMP]

At the first place, some experimental knowledges on the biodistribution of IMP were described for the understand of this agent. And on the basis of our clinical experience, the usefulness of cerebral perfusion imaging using SPECT and IMP was reviewed. The patients with possible ischemic cerebral diseases such as infarction, TIA and RIND are main candidates for this examination. Clinical significance of the so-called "redistribution" of IMP was discussed in detail. Dementia and epilepsy are considered to be the other indication. With improvement of the method, cerebral perfusion imaging may be accepted as essential test in the hospital dealing with the patient with neuropsychiatric deficits.

Critical cerebral blood flow thresholds studied by SPECT using xenon-133 and iodine-123 iodoamphetamine

Regional cerebral blood flow (rCBF) was assessed in patients with cerebrovascular diseases (CVD) by single photon emission computed tomography (SPECT) using 133Xe and N-isopropyl-p-[123I]iodoamphetamine ([123I]IMP). The purpose of this study was to determine the infarcted and symptomatic blood flow thresholds of cerebral cortex by SPECT. In the 133Xe inhalation method rCBF was calculated by employing the Celsis modification of the Kanno and Lassen algorithm. In the [123I]IMP SPECT quantitation was obtained by counting-rate ratio for the low flow lesion to the contralateral homologous region which was presumed to be normal (Lesion/Normal ratio, L/N ratio). The infarcted and symptomatic blood flow thresholds by 133Xe SPECT was 19-23 and 33-36 ml/100 g/min, respectively. While, those of L/N ratio in the [123I]IMP SPECT were 39-48 and 65-72%, respectively. There was a significant correlation between the ischemic degrees evaluated by 133Xe and [123I]IMP SPECT studies.

[Sequential changes of the cardiomyopathy in Duchenne muscular dystrophy by 201Tl myocardial SPECT]

201Tl myocardial SPECT was performed to evaluate cardiomyopathy in Duchenne type of progressive muscular dystrophy (DMD). Follow up SPECT images of the same patients were also obtained about 1 year after the first scan. Cases subjected to study were 10 DMD. At the first study the hypoperfusion area of the left ventricular muscle was observed in 6 cases (60%) out of 10. At the second study the hypoperfusion areas became wider and lower in 4 out of 6 cases (66.7%). The new hypoperfusion area which was not demonstrated at the first study was observed at the second study in one case of these cases. These results suggested that the positive rate of cardiomyopathy in DMD by 201Tl myocardial SPECT was high, and 201Tl myocardial SPECT is a useful examination to detect the change of myocardial damage in DMD.

Comparative study of regional cerebral blood flow images by SPECT using xenon-133, iodine-123 IMP, and technetium-99m HM-PAO

Regional cerebral blood flow (rCBF) was measured by single photon emission computed tomography (SPECT) using 133Xe, N-isopropyl-p-[123I]iodoamphetamine ([123I]IMP) and [99mTc] hexamethylpropyleneamine oxime ([99mTc]HM-PAO) in 24 patients with cerebrovascular diseases. The greatest advantage of 133Xe SPECT was to be able to provide absolute rCBF values without arterial sampling. However, its image quality was very poor. Iodine-123 IMP SPECT provided rCBF images of higher quality and it had good correlation to 133Xe SPECT. Iodine-123 IMP SPECT provided the best images to detect mild ischemic lesions. It could detect obstructive or stenotic changes of large cerebral arteries very well except for a moderate stenosis of internal carotid artery. Technetium-99m HM-PAO SPECT also provided very good rCBF images and it had good correlation to 133Xe SPECT. However, the count-density ratios for the ischemic lesions to the contralateral presumed normal areas of [99mTc] HM-PAO SPECT were significantly higher than those of [123I]IMP SPECT.

Pseudoaneurysm of the celiac artery demonstrated by radionuclide angiography

The usefulness of radionuclide angiography in patients with vascular occlusion or aneurysm is well documented. In this paper, a rare case of pseudoaneurysm of the celiac artery demonstrated by radionuclide angiography is reported.

Unusual uptake and retention of I-123 IMP in brain tumors

Ten patients with unusual uptake and retention of I-123 IMP in their brain tumors were studied. Of these ten patients, five had meningiomas and the remaining five had glioblastoma, malignant astrocytoma, malignant lymphoma, metastatic brain tumor, and cellular blue nevus. Six tumors (five meningiomas and the glioblastoma) showed short term retention of I-123 IMP. Three tumors (the malignant astrocytoma, the malignant lymphoma, and the metastatic brain tumor) showed a delayed increase of radioactivity and the cellular blue nevus showed a gradual increase and long term retention of the tracer.

Dynamic SPECT with iodine-123 IMP in meningiomas

Dynamic studies of single photon emission computed tomography (SPECT) were performed with intravenous administration of N-isopropyl-p-[123I]iodoamphetamine ([123I]IMP) in 12 patients with meningiomas. Their vascularities were also assessed by angiography. Regions of interest (ROIs) were placed over the lesion and the contralateral presumed normal area, the symmetrical one if possible. Time-activity curves (TACs) were then constructed and the counting-rate ratio for the lesion to the contralateral presumed normal area (L/N ratio) was calculated in the first image of the dynamic SPECT. TACs were classified into three types: type I, an initial high uptake and rapid washout type, type II, an initial high uptake and slow washout one, and type III, an initial low uptake one. L/N ratios of angioblastic meningiomas were over 300%, while those of many fibroblastic ones were under 100%, at most 105%. We compared L/N ratios with angiographic vascularities and histologic types and conclude that dynamic SPECT with [123I]IMP is the examination of choice for evaluating the vascularity of lesions.

Tc-99m hexamethylpropylene-amine oxine (HM-PAO) uptake in a bone metastasis

Uptake of Tc-99m Hexamethylpropylene-amine Oxine (HM-PAO) was seen in bone metastases from carcinoma of the lung. The uptake was prominent when compared to Tc-99m MDP, I-123 IMP, and Ga-67 citrate. Brain imaging with Tc-99m HM-PAO and N-isopropyl-p-[I-123] iodoamphetamine (IMP) is now frequently performed. Uptake of these agents has been reported in brain tumors and melanomas. In this report, uptake of Tc-99m HM-PAO in a metastatic lesion in bone is discussed.

Gallium scintigraphy in patients with adult T-cell leukemia lymphoma

Gallium scintigraphy was evaluated in 25 patients with adult T-cell leukemia lymphoma (ATLL). Anterior and posterior images were obtained at 72 h after administration of 3 mCi 67Ga-citrate using a gamma camera (Maxi-Camera 400 T, General Electric Co.) with a medium energy standard parallel hole collimator. Abnormally high accumulations were observed in 17 out of 25 cases (superficial lymph node, 8; hilar and mediastinal lymph node, 7; paraaortic lymph node, 2; lung, 9; liver, 1; bone, 1). There were 10 malignant lesions detected by 67Ga scintigraphy in 9 out of 17 cases (superficial lymph node, 1; hilar and mediastinal lymph node, 6; paraaortic lymph node, 1; liver, 1; bone, 1). White blood cell count and serum LDH levels were raised in patients with abnormally high accumulations of 67Ga. In conclusion, 67Ga scintigraphy seemed to be a useful examination to detect malignant lesions in patients with ATLL.

Gallium-67 scintigraphy in patients with hemochromatosis treated by deferoxamine

Gallium scintigraphy was performed as an aid for determining the presence or absence of malignant neoplasm in two patients with hemochromatosis treated by deferoxamine. However, gallium scan images could not be obtained. So gallium scintigraphy was performed once more to investigate the cause of low activity. Both patients had heavy urinary excretion of gallium in the first 24 hrs after the injection, and activity was very low on the day of examination. This phenomenon may be attributed to the effect of deferoxamine which is highly bound to the gallium.

Early and delayed single photon emission CT in various cerebral diseases using N-isopropyl-p-(123I)iodoamphetamine

Early and delayed single photon emission computed tomography (SPECT) using N-isopropyl-p-(123I)iodoamphetamine (IMP) was performed on 28 subjects (2 normal, 12 with cerebrovascular diseases and 14 with brain tumors) to evaluate the reversibility of the cerebral abnormality and cerebral viability. The results were compared with X-ray CT, 99mTc brain scintigraphy and rCBF by 133Xe inhalation method. Three types of IMP kinetics were observed. Initial hypoactivity that changed over 4 to 6 hours approaching a normal pattern suggests a hypofunctional parenchyma without significant tissue damage: long-lasting abnormalities on IMP SPECT indicates cellular damage.

The distribution of radioiodine-labeled N-isopropyl-p-iodoamphetamine in permanently ischemic brain of the Mongolian gerbil

In a study of the distribution of N-isopropyl-p-131I-iodoamphetamine (IMP) in the permanently ischemic brain of 35 mongolian gerbils, the right common carotid artery was ligated under ether anesthesia. After given time intervals, 1.35 MBq (50 microCi) of IMP was injected into 17 gerbils which had severe neurological symptoms, and into 3 normal gerbils for controls. One minute there after each gerbil was sacrificed and brain autoradiography was performed. The activity of IMP in various parts of the brain was calculated from each autoradiogram. Low perfusion areas were observed in the right cerebral hemisphere and the brain stem (5-25% of normal value) from the first minute up to 24 h after ligation. In addition, low perfusion areas were also observed in the left cerebral hemisphere (40-60% of normal value) which represented a remote effect. These results suggest the usefulness of IMP for demonstrating cerebral ischemia and diaschisis.

The Distribution of Radioiodine-Labeled N-Isopropyl-plodoamphetamine in Permanently Ischemic Brain of the Mongolian Gerbil

In a study of the distribution of N-isopropyl-p-131l-iodoamphetamine (IMP) in the permanently ischemic brain of 35 mongolian gerbils, the right common carotid artery was ligated under ether anesthesia. After given time intervals, MBq (50μCi) of IMP was injected into 17 gerbils which had severe neurological symptoms, and into 3 normal gerbils for controls. One minute there after each gerbil was sacrified and brain autoradiography was performed. The activity of IMP in various parts of the brain was calculated from each autoradiogram. Low perfusion areas were observed in the right cerebral hemisphere and the brain stem (5-25% of normal value) from the first minute up to 24 h after ligation. In addition, low perfusion areas were also observed in the left cerebral hemisphere (40-60% of normal value) which represented a remote effect. These results suggest the usefulness of IMP for demonstrating cerebral ischemia and diaschisis.

The distribution of N-isopropyl-p-iodoamphetamine in temporary ischemic brain of the mongolian gerbil

We studied the distribution of N-isopropyl-p-[131I]-iodoamphetamine (IMP) in the ischemic brain of 44 mongolian gerbils. The right common carotid artery was temporarily occluded by a clip and recirculated 3 h later. After given time intervals, 50 microCi of IMP was injected into 18 gerbils which had symptoms. One min after injection (or 10 min, 1 h, or 6 h after injection in other gerbils), each gerbil was killed and autoradiography was performed. IMP activity in various parts of the brain was calculated as %Dose/g from each autoradiogram. At one min after recirculation, partial no flow phenomenon was observed in the right cerebral hemisphere. From 10 min to 24 h after recirculation, a high uptake region was observed partially in the right cerebral hemisphere and thalamus. The high activity disappeared rapidly 10 min after injection. It seemed that this high uptake indicated luxury perfusion at the location of severe tissue damage. In the left side, the low perfusion recovered to an almost normal value at one to three days after recirculation. These results suggested the possibility that IMP could demonstrate luxury perfusion and diaschisis.

Optimal positioning for CT examinations of the skull base. Experimental and clinical studies

To evaluate the most appropriate CT angles for the skull base, four adult phantom skulls of various shapes were examined by CT. 15 osseous sites in each skull base were selected and the optimum angle for their delineation was determined. Using Reid's base line (0 degree), many sites could be imaged best at angles up to +20 degrees, and +10 degrees was found to be optimum. Examinations of patients using OM-line as a reference disclosed imaging rates in excess of 70% for sites other than the hypoglossal canal, the optic canal and foramen rotundum, which are in horizontal planes.

Mismatch between iodine-123 IMP and technetium-99m HM-PAO brain perfusion imaging in a patient with meningioma

The discrepancy between three methods for cerebral perfusion imagings in the case of a man with meningioma is presented. Imaging with N-isopropyl-P-[I-123] iodoamphetamine (IMP) showed no activity in the tumor. Imaging with Tc-99m hexamethylpropyleneamine oxime (HM-PAO) and the local cerebral blood flow (LCBF) image with Xe-133 inhalation showed high tumor activity. IMP is a more accurate method for imaging the brain tissue blood flow.

Biodistribution of N-isopropyl-p-iodoamphetamine in the rat brain

The biodistribution of N-isopropyl-p-iodoamphetamine (IMP) was studied in the rat brain. 131I-labelled IMP was injected intravenously in awake animals. Activities in the brain of Sprague-Dawley rats were 2.68-3.22 (% dose/g) in the cortex and 0.59-0.66 (% dose/g) in the white matter at 1 min p.i. Activities in the cortex were slightly increased at 60 min p.i., while activities in the white matter increased markedly at 60 min and 6 h p.i. Therefore, the cerebral cortex-to-white matter ratio decreased from 5 to 1 within 60 min after injection. Autoradiograms of the rat brain at 1-10 min p.i. showed high contrasts. Activities were high in the cortex and low in the white matter, but homogeneous at 60 min-6 h. IMP seems to be a useful agent for cerebral perfusion imaging in the early phase after injection. Knowledge of biodistribution of this agent is considered to be indispensable for the interpretation of images.

[Clinical evaluation of serum neuron-specific enolase levels in patients with lung cancer]

Serum neuron-specific enolase (NSE) levels were studied in 105 patients with malignant neoplasms (lung cancer 38, others 67), 13 patients with various benign diseases and 7 healthy adults. The mean serum NSE level in adult control subjects was 7.4 +/- 0.8 ng/ml, and cut off level was decided 10 ng/ml. Serum NSE levels were elevated in 14/38 (37%) of patients with lung cancer and in 14/67 (21%) of patients with the other malignant neoplasms. In patients with benign diseases, serum NSE level was elevated only in one patient with pituitary adenoma. In 7 patients with small cell lung cancer, the positive rate was higher (86%) than in those with non-small cell lung cancer (26%), and serum NSE levels were higher than 25 ng/ml except one case. There was no correlation between serum NSE and CEA (carcinoembryonic antigen) levels in patients with small cell lung cancer, also in patients with lung cancer. The measurement of serum NSE level seemed to be useful for diagnosis in patients with small cell lung cancer.

Bullous lesions detected by computed tomography

An analysis was made of bullous emphysema detected by plain chest radiography and computed tomography (CT). Bullous lesions were detected in 43 of 214 patients who had thoracic CT as a further assessment of their pulmonary, pleural, and mediastinal abnormalities. Plain chest radiography failed to detect the bullous lesions in 17 (39.5%) out of the 43 patients. Bullous lesions unrecognizable on plain radiographs ranged from 1.0 to 2.0 cm in size, were few in number, and were situated on the mediastinal side of the lung in many patients. CT is a sensitive method for detecting bullous lesions. Therefore, we consider it necessary to perform CT when needle biopsy for a previously known pulmonary lesion is taken into account, because knowledge of coexisting bullous lesions may be useful in preventing the occurrence of severe pneumothorax as complication.

Diagnosis of diffuse hepatocellular diseases using SPECT

In the scintigraphic diagnosis of diffuse hepatocellular diseases, increased splenic uptake of colloids and splenomegaly are helpful signs. To quantify these patterns, the volume and activity of liver and spleen were measured by using single photon emission computed tomography (SPECT). The spleen-to-liver (S/L) ratios in volume and activity that were calculated from SPECT images were estimated in normal individuals and in patients with diffuse hepatocellular diseases. The maximum normal limits of S/L ratios of volume, activity, and activity/volume were predicted as 0.19, 0.087, and 0.72 (mean +/- 2 s.d.). Twenty-two of twenty-three patients (96%) with liver cirrhosis had at least two elevated S/L ratios, and three elevated S/L ratios could clearly differentiate the patient with liver cirrhosis from normal individuals. On the other hand, only six patients (32%) with chronic hepatitis had elevation of any S/L ratio. Abnormal S/L ratios of activity/volume in the range from 0.72 to 1.05 were not obvious on planar or SPECT images.

Hepatic anomalous lobulation demonstrated by liver and hepatobiliary scintigraphy

The use of liver and hepatobiliary scintigraphy for evaluation of the hepatobiliary system in patients with hepatic disease is now widespread. In the present case, the usefulness of liver and hepatobiliary scintigraphy for the diagnosis of liver malformation is described.