[Single photon emission computed tomography (SPECT) using 99mTc-hexamethyl propyleneamine oxime in patients with ischemic cerebral diseases: comparative study of N-isopropyl-p-[123I]-iodoamphetamine and 99mTc-DTPA SPECT]

In order to confirm the diagnosis and clarify the pathophysiology in the ischemic lesions in brain, 99mTc-PAO SPECT was performed in 42 patients with ischemic cerebral diseases, and the findings on 99mTc-PAO SPECT were compared with those on 123I-IMP or 99mTc-DTPA SPECT, and on X-CT. Furthermore, count ratio of ischemic lesion to normal contralateral region (I/N) was used for the evaluation of the detectability in the lesions on 99mTc-PAO or 123I-IMP SPECT, and less than 0.95 of I/N ratio was defined as the decreased accumulation. The detectability of ischemic lesion in brain with 99mTc-PAO SPECT was 80%, which was superior to that (60%) of LDA on X-CT. Especially, 99mTc-PAO SPECT was useful in cases which were examined early after the onset of the attack. On the other hand, 123I-IMP SPECT showed the best result (88%) in the detectability, and furthermore I/N ratio on 123I-IMP SPECT was lower than that on 99mTc-PAO SPECT. In the delayed phase on 123I-IMP SPECT the redistribution was observed in 30%, while on 99mTc-PAO SPECT it was done in none of them. The accumulation of 99mTc-DTPA in brain was found in 6 of 14 cases (43%), and 2 cases among them also showed the accumulation of 99mTc-PAO in the ischemic lesion. In such cases the destruction of BBB might be considered as the cause of the accumulation of 99mTc-PAO. Thus, 99mTc-PAO SPECT was thought to be useful method in clinical studies of the ischemic cerebral diseases.

[Single photon emission computed tomography by using N-isopropyl-p-[123I]-iodoamphetamine and 99mTc-hexamethyl propyleneamine oxime in a patient with herpes simplex encephalitis]

Single photon emission computed tomographies (SPECTs) by using N-isopropyl-p-[123I-IMP]-iodo-amphetamine (123I-IMP) and 99mTc-hexamethyl propyleneamine oxime (99mTc-HM-PAO) were serially performed in a 70 yrs. old male with herpes simplex encephalitis (HSE), and the chronological changes of accumulations were studied. Accumulations of both 123I-IMP and 99mTc-HM-PAO increased initially, and then decreased with the stage of HSE being advanced. The sequential appearance of the lesion in HSE with 123I-IMP and 99mTc-HM-PAO SPECTs was as same as that reported previously by X-CT; beginning at the temporal lobe with eventually being spread to the occipital and frontal lobe. Furthermore, it was shown that findings of both SPECTs could reflect considerably the clinical features, and the laboratory data in central spinal fluid. Thus, 123I-IMP and 99mTc-HM-PAO SPECTs seemed to be a useful tool in the diagnosis, deciding of whether the treatment was suspended or continued, and clarifying the pathophysiology in HSE.

[A case of Creutzfeldt-Jakob disease followed up by N-isopropyl-[123I]-p-iodoamphetamine and 99mTc-hexamethylpropyleneamine oxime SPECT]

N-isopropyl-[123I]-p-iodoamphetamine (123I-IMP) and 99mTc-hexamethylpropyleneamine oxime (99mTc-HM-PAO) SPECT were performed in a 66 yrs-old female patient with Creutzfeldt-Jakob disease (CJD). The decreased accumulation of both radiopharmaceuticals, which localized initially in the focal regions and progressed eventually to the whole brain, were observed in the early stage of CJD, when no abnormal findings were obtained on X-CT. Although the redistribution of 123I-IMP was recognized in the relatively early stage in which the accumulation was significantly decreased, it disappeared with the progression of the disease. The accumulation of both radiopharmaceuticals which decreased remarkably in the early stage of CJD was sustained in low level during the chronic stage. The accumulation ratio of 99mTc-HM-PAO, after second examinations, to that on first SPECT was lower than those of 123I-IMP. It was suggested, as this cause, that the difference of the accumulation mechanism of both agents might be concerned. Thus, it is interested to follow up a patient with CJD by using 123I-IMP and 99mTc-HM-PAO SPECT, and this modality will provide a useful information to clarify the pathogenesis of CJD.

[Clinical usefulness of a dual photon absorptiometry system using X-ray for peripheral bone--comparison with a single photon absorptiometric system]

A newly developed dual photon absorptiometry system (DCS-600, ALOKA Co., LTD.) using two monochromatic X-rays for the determination of bone mineral in the peripheral bone was fundamentally studied, in comparison to single photon absorptiometry system (SPA). The accuracy and precision in DCS-600 were equal to or better than SPA system. Furthermore, in DCS-600 the forearm could be imaged, and the manipulation was easy. Thus DCS-600 was found to be a good instrument as a quantifying system of bone mass.

Visualization of ocular melanoma with N-isopropyl-p-[123I]-iodoamphetamine

In a patient with ocular melanoma, scintigraphy with N-isopropyl-p-[123I]-iodoamphetamine [( 123I]IMP) clearly delineated the histologically proven ocular lesion. In a tissue distribution study, using the resected specimen, a significantly high accumulation of the radioactivity was confirmed in tumor tissue. Thus, [123I]IMP scintigraphy provided specific localization of an ocular melanoma.

[Detection of varicocele by using 99mTc-diethylenetriamine pentaacetic acid human serum albumin (99mTc-DTPA human serum albumin)]

In order to detect the varicocele, scrotal scintigraphies by using 99mTc-HSA-D were performed in 14 patients with male infertile or palpable mass in left scrotum on physical examinations. Abnormal pooling of 99mTc-HSA-D, indicative of varicocele lesion, could be found in left scrotum in 9 cases, confirmed surgically or clinically. Compared with 99mTc-HSA, 99mTc-HSA-D was superior in high uptake ratio of varicocele to soft tissue and in nonvisualization of bladder. Thus, 99mTc-HSA-D scrotal scintigraphy seemed to be of a great use to detect the varicocele.

Visualization of soft tissue by technetium-99m MDP in polymyositis. Case reports

Two patients with polymyositis showed abnormal muscular uptake of Tc-99m-methylene diphosphonate (MDP) during routine bone imaging. Imaging with Tc-99m MDP is a useful tool in monitoring the activity of the diseased muscle.

Usefulness of bone imaging in diagnosis of sternocostoclavicular hyperostosis

Four patients with sternocostoclavicular hyperostosis showing characteristic abnormal uptake on bone imaging are described. Bone imaging was useful in the diagnosis of sternocostoclavicular hyperostosis.

[Clinical study on the measurement of squamous cell carcinoma (SCC)--related antigen in SCC]

By using a RIA Kit for squamous cell carcinoma (SCC) antigen, extracted and purified this substance from liver metastasis of SCC of the uterine cervix, a fundamental and clinical study has been done. Based on the fundamental study, it was shown that this kit was useful clinically. High concentrations of serum SCC related antigen were observed in squamous cell carcinoma of the lung, head and neck, and uterus. It was recognized that the measurement of serum SCC related antigen was useful in not only diagnosis, but also in the evaluation of effectiveness of therapy or prediction of recurrence. In particular, as there is a lack of reliable tumor markers in head and neck tumors, good results can be anticipated from the measurement of SCC related antigen in such cases.

The usefulness of bone-marrow scintigraphy in the detection of bone metastasis from prostatic cancer

We used a combination of bone and bone-marrow scintigraphy to study 25 patients with prostatic cancer. Of the 18 cases whose 99mTc-methylene diphosphonate (MDP) bone scans showed hot spots in the lower lumbar region of the spine and/or the pelvic bone, 8 had normal bone-marrow scintigrams. These 8 patients were subsequently shown to have senile, degenerative changes of the spine. On the other hand, in 9 of the 10 patients whose bone-marrow scintigrams showed accumulation defects, follow-up study and characteristic X-ray findings confirmed the presence of metastases. In all 6 cases with extensive bone metastases shown by 99mTc-MDP bone scintigraphy, 99mTc-sulphur-colloid bone-marrow scintigraphy showed multiple accumulation defects. In conclusion, bone-marrow scintigraphy was found to be useful in distinguishing metastatic lesions from benign degenerative changes in the cases with suspected bone involvement, as well as in evaluating equivocal lesions in the pelvis.

[Clinical study of the measurement of tissue polypeptide antigen in patients with breast cancer]

Tissue polypeptide antigen (TPA) concentrations in patients with breast cancer were measured using a radioimmunoassay (RIA) kit. Although this RIA kit presented some problems in the dilution test of high-concentration samples, it was found to be adequate for clinical use. It was shown that the measurement of serum TPA concentration was useful in monitoring the local recurrence, for the early diagnosis of distant metastasis and for evaluating the therapeutical effect after surgery. TPA concentration showed no correlation with CEA concentration. Therefore, in order to raise the rate of diagnostic success, simultaneous measurement of both TPA and CEA was essential.

Metastatic medullary thyroid cancer: localization with iodine-131 metaiodobenzylguanidine

A patient in whom metastatic medullary thyroid cancer was diagnosed underwent a scintigraphic examination using [131I]MIBG. Multiple hot lesions and diffuse hepatic uptake were noted corresponding to bone and liver metastases. Iodine-131 MIBG may prove to be useful for scintigraphic localization and for the treatment of medullary thyroid cancer as in pheochromocytoma and neuroblastoma.

Usefulness of liver scan using 99mTc-phytate in diagnosis of partial diaphragmatic eventration

Partial diaphragmatic eventration, when occurring at uncommon sites, is difficult to diagnose when only using a plain X-p and fluoroscopy. We experienced an unusual variety of this disorder. In order to diagnose this case, liver scintigraphy using 99mTc-phytate was performed, and we were able to make a definite diagnosis without other invasive examinations.