[Evaluation of cerebral hemodynamics by 123I-IMP in cerebral AVMs before and after operation by using SPECT].

To evaluate cerebral hemodynamics by N-isopropyl-p-[123I]-iodoamphetamine (123I-IMP) preoperative and postoperative (after 1 day, and after 7-10 days) regional cerebral blood flow scan, 6 arteriovenous malformations (AVMs) which performed total removal operations were studied by using a ring type SPECT "HEADTOME". We performed the dynamic scan just after the intravenous injection of 222 MBq (6 mCi) of 123I-IMP, then the static scan 20 minutes after the intravenous injection. In preoperative dynamic scans of all cases, only the first frame image showed the increased activity on the nidus probably because of the blood pool.

[Crossed cerebellar diaschisis in hydrocephalus--a case report].

A case of hydrocephalus in which a crossed cerebellar diaschisis with single photon emission CT (SPECT) using 123I-iodoamphetamine (123I-IMP) disappeared by a ventriculo-peritoneal shunting operation, was reported. A 54-year-old female had a clipping surgery for a aneurysm of the left middle cerebral artery on April 9, 1987. Post-operatively, she had a transient mild aphasia.

Isoproterenol stress thallium scintigraphy for detecting coronary artery disease.

The value of exercise thallium scintigraphy in detecting coronary artery disease is well established. However, there are at times situations in which the exercise test cannot be readily used. Isoproterenol (ISP) stress ECG (ISP-ECG) is reportedly a useful method in diagnosing coronary artery disease.

[Development of a new quantitative analysis for thallium myocardial SPECT images--quantitative STEREO-VIEW method and evaluation of its clinical usefulness].

We have developed a three-dimensional quantitative display method, Quantitative STEREO-VIEW method (STEREO-VIEW method), for analysis of thallium (Tl) myocardial SPECT images and have evaluated its clinical usefulness. SPECT data were obtained immediately and 4 hours after the exercise, and contour lines for outer edges of left ventricular (LV) myocardium were detected from 10 slices of short axial images in delayed scan. LV wall was divided into 510 segments by dividing each slice into 51 sectors and LV myocardium was three-dimensionally reconstructed.

[The relationship between N-isopropyl-p-[123I]iodoamphetamine accumulation in the brain and its dynamics in other organs].

Single photon emission computed tomography of the brain and dynamic scintigraphy of the lung and liver with N-isopropyl-p-[123I]iodoamphetamine (IMP) were performed in 21 patients with and without cerebrovascular diseases to determine the relationship between IMP accumulation in the brain and its dynamics in other organs. The D/E ratios of the lung, liver and brain were calculated dividing the counts of the delayed image by that of the early image. The brain D/E ratio in the normal hemisphere was well correlated with the lung D/E ratio.

[Bone dynamic study--evaluation for factor analysis of hip joint].

Factor analysis was applied to dynamic study of Tc-99m MDP for the evaluation of hip joint disorders. Fifteen patients were examined; eight were normal, six were osteoarthritis in which one accompanied synovitis was included, and one was aseptic necrosis on the head of the femur. In normals, according to the Tc-99m MDP kinetics, three factor images and time-activity curves were obtained which were named as blood vessel, soft tissue, and bone factor images and curves.

Effect of nifedipine on left ventricular function during exercise in patients with stable effort angina. Relation of its efficacy to the severity of coronary artery disease.

To evaluate whether the effect of nifedipine on left ventricular function relates to the severity of coronary artery disease (CAD) or not, supine graded ergometer exercise testing was performed before and after sublingual administration of 10 mg nifedipine in 24 patients with stable effort angina. To minimize the effect of nifedipine on myocardial oxygen consumption, exercise before and after nifedipine was discontinued at the same target rate pressure product. Percent (%) left ventricular ejection fraction (EF) [EF during exercise/EF at rest.

[Clinical usefulness of physiologic components obtained by factor analysis--application to 99mTc-DTPA renography].

The clinical usefulness of physiological components obtained by factor analysis was assessed in 99mTc-DTPA renography. Using definite physiological components, another dynamic data could be analyzed. In this paper, the dynamic renal function after ESWL (Extracorporeal Shock Wave Lithotripsy) treatment was examined using physiological components in the kidney before ESWL and/or a normal kidney.

[Reverse redistribution in the stress thallium scan--correlation of coronary blood flow and myocardial damage].

In order to make clear 'reverse redistribution (RR)' phenomenon in stress thallium scan we investigated 477 consecutive patients who were consisted of 74 cases with PTCA (PTCA group), 86 cases with coronary artery bypass graft (CABG group) and 317 cases without any revascularization (N group). RR was detected in 12 cases out of PTCA group (16%), in 11 cases out of CABG group (13%) and in 10 cases out of N group (3.2%), and the incidence of RR in PTCA or CABG group was higher than that of N group (p less than 0.

Analysis of thallium-201 myocardial SPECT images using fuzzy set theory.

Using the fuzzy set theory, a method was developed for analyzing the extent and severity of ischemia by comparing the exercise and delayed SPECT images with Thallium-201. For each short axial image (slice) for exercise and delayed study, a defect probability matrix (DPM) is created so that it shows the severity of ischemia of myocardium in that slice. Each slice is divided into 8 equi-angle sectors, and the left ventricle (LV) also is divided into 8 equi-angle vertical sectors from apex to base.

[Evaluation of the system performance and clinical images of the single photon emission computed tomography for head using ring arranged detector].

To evaluate the system performance, several preoperational fundamental tests of single photon emission computed tomography (SPECT) were carried out. Spatial resolutions (FWHM) measured with the point-spread functions of a 99mTc line source were 12.5 mm with a high resolution (HR) collimator and 17.

[99mTc-DMSA renal uptake in urological diseases measured from renal tomographic images using single photon emission computed tomography (SPECT)].

To determine renal function, 99mTc-DMSA renal uptake was measured from renal tomographic images obtained by single photon emission computed tomography (SPECT). A total of 77 tests was conducted on 73 patients with various diseases in the kidneys and urinary tract to determine renal uptake. The correlation coefficient(r) between total renal volume and total renal uptake was 0.

Evaluation of regurgitant fraction of the left ventricle by gated cardiac blood-pool scanning using SPECT.

Regurgitant fraction (RF) of patients with and without mitral regurgitation (MR) and/or aortic regurgitation (AR) was evaluated by gated cardiac blood-pool scanning using single photon emission computed tomography (SPECT). Using the stroke count image of a short-axis tomogram to separate the right atrium and ventricle, the left ventricular stroke count (LVSC) and right ventricular stroke count (RVSC) were determined. The RF equaled (LVSC - RVSC)/LVSC.

Automated body contour detection in SPECT: effects on quantitative studies.

To perform accurate in vivo quantitation by single photon emission computed tomography, we have developed a new method for detecting body contours for the correction of tissue attenuation. Our method can rapidly derive the best fit contours throughout the body by using the measured axial length of the patient body and Fourier filtering the detected contours which are defined by a unique bit-plane algorithm. We have also evaluated the effects of the body contours on the reconstructed images by using various attenuation correction techniques including a precorrection method (Sorenson, 1974), a postcorrection method (Chang, 1978), a weighted backprojection method, and a radial post correction method (Tanaka, 1983 and 1984).