[en] Ultrahigh speed CT is called electron beam scanning type CT, which is a new type CT using an electron gun, and its clinical application has been advanced mainly in USA and Japan. The features of this ultrahigh speed CT are short scanning time and repetition time, and the change of the shapes of organs like pulsing heart and the changes of the shapes and densities of organs like respiring lung can be known by this means. The equipment is IMATRON C-100 using an electron beam scanning type x-ray generator. There are three methods of photographing with the IMATRON C-100, that is, cine mode, flow mode and volume mode. These methods are briefly explained. The primary purpose of applying CT to heart diseases is the accurate diagnosis of cardiac infarction. The ultrahigh speed CT can do the excellent detection of ventricular aneurysm. Also its application to coronary artery calcification, myocardial diseases and heart tumors is described. As for its application to the radiation therapy of chest diseases, the change of lung density in radiotherapy, the change of the CT values of lungs, and the application to the treatment are reported. (K.I.)

[en] Magnetic resonance images (MRI) of the normal cruciate ligament (CL) in ten cases, disruption of the anterior CL in 5 cases and sprain fracture of the tibia at the insertion of the anterior CL were obtained with a 0.1 Tesla resistive magnet. A normal CL was well demonstrated as a black band, using a spin-echo sequence with 5 mm slice thickness and an oblique plain which contained each CL. Disruption of the anterior CL and sprain fracture of the tibia were correctly diagnosed by MRI. A valuable role for MRI in the assessment of cruciate ligament injuries was suggested. (author)

[en] One patient with complete agenesis and 9 patients with partial dysgenesis of the corpus callosum were studied by magnetic resonance imaging (MRI) using a resistive magnet. In 9 patients with partial dysgenesis, 8 had a posterior defect while the remaining one had an anterior defect. MRI demonstrated size and shape of the corpus callosum precisely together with associated abnormalities i. e., lipoma, absence of the septum pellucidum, Chiari I malformation and cystic disease. MRI is the best technique in the evaluation of the corpus callosum. (author)

[en] In this study, the left ventricular diameter, the interventricular septum thickness, and the left atrial internal diameter were measured by ultrafast computed tomography and echocardiography. The fractional shortening was calculated as the difference between end-diastolic and end-systolic left ventricular diameter divided by end-diastolic left ventricular diameter. The fractional shortening by both methods was compared. The correlation coefficients between the results by both methods were 0.78 at the end-diastolic left ventricular diameter, 0.84 at end-systolic left ventricular diameter, 0.74 at the interventricular septum thickness and 0.78 at fractional shortening. The correlation coefficient by both methods was low in the left atrial diameter. The fractional shortening by ultrafast CT tended to be lower than that by echocardiography. Although the fractional shortening by ultrafast CT is not measured at the veritable long axis which is only the table sliding to the left for 25 degrees, the datum is useful as an index of the left ventricular function. (author)

[en] Magnetic resonance (MR) imaging was performed in fifty normal pituitary glands, ten pituitary microadenomas, and twelve adenomas with extrasellar extension using a 0.15 Tesla resistive magnet. The average height of normal glands was 5.6 +- 1.2 mm, whereas that of microadenomas was 6.8 +- 1.0 mm. The superior surface and internal texture of these conditions were well delineated. Adenomas that showed extrasellar extension together with surrounding structures were well demonstrated on sagittal and coronal scans. It can be expected that with further technical developments MR imaging will play an important role in the clinical management of pituitary adenomas. (author)

[en] Computed tomography (CT) of 85 patients was reviewed to investigate normal appearances of the pericardium. The pericardium was identified as a thin curvilinear soft tissue density in 80 out of 85 patients, best seen anterior to the right ventricle at the coronary sinus level. The CT appearances of 44 pericardial diseases, including effusions, thickening, cysts, tumors, pericardial defects and false left ventricular aneurysm, were reviewed to evaluate the usefulness of CT in the diagnosis of pericardial diseases. CT was useful in the detection of various pericardial abnormalities and provides accurate information. (author)

[en] Longitudinal relaxation times (T₁) of 36 brain tumors were calculated with a magnetic resonance imaging system of 0.15 Tesla resistive magnet. T₁ values of brain tumors were longer, in most instance, than the normal brain. Epidermoid with adipose tissue showed very short T₁ value, while cystic tumors showed very long T₁ values. Most of meningiomas showed T₁ values similar to normal gray matter. T₁ values had no correlation with tumor maturation. (author)

[en] Ultrafast computed tomography (UFCT) is a new diagnostic modality that includes not only imaging of cardiac structures, but also movement of cardiac muscles and valves. It can be useful in the evaluation of prosthetic valves, because the scan time is extremely short and whole cardic structures are imaged with a slice thickness of 8 mm and within 7 cardiac cycles. We review our experience using UFCT to observe prosthetic valve function in 22 cases with various valvular diseases. (author)

[en] Ultrafast computed tomography was performed in 30 patients with hypertrophic cardiomyopathy and images were assessed on variability of left ventricular hypertrophy, the pattern of left ventricular contraction, right ventricular hypertrophy, dilatation of the left atrium, and thickening of the mitral valve. Fifteen (50.0%) of 30 patients had asymmetric septal hypertrophy, six (20.0%) had diffuse hypertrophy, and nine (30.0%) had apical hypertrophy. In eleven patients with asymmetric septal hypertrophy and two with apical hypertrophy, non-hypertrophied segments in end-diastole showed vigorous contraction. Sixteen patients showed homogeneous left ventricular contraction and one showed partial apical contraction. Right ventricular hypertrophy was noted in 12 patients (40.0%), dilatation of the left atrium in 13 patients (43.3%), and mitral valve thickening in three (10.0%). Ultrafast computed tomography was useful in the evaluation of apical hypertrophy and right ventricular hypertrophy, which could be difficult to obtain by echocardiography. (author)

[en] Computed tomography (CT) provides noninvasive information in the evaluation of abnormalities of the gastrointestinal tract by direct imaging of the bowel wall and adjacent mesentery. Several prior studies have discussed the variable CT appearances of mesenteric abnormalities, such as lymphoma, metastasis, inflammatory disease and edema. Although mesenteric thickening was mentioned in these studies, no study has provided a detailed analysis of the CT appearance of the thickened mesentery. Two characteristic types of mesenteric thickening were identified in 47 patients. Type I is 'intramesenteric thickening', which was noted in 25 patients with vascular obstruction, inflammatory disease and edema. Type II is 'mesenteric surface thickening', which was noted in 22 patients with peritonitis carcinomatosa, peritoneal mesothelioma, tuberculous peritonitis and pseudomyxoma peritoneai. An understanding of these two types of mesenteric diseases is important in the identification of mesenteric pathology. (author)