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K Sadamoto

Publications and source records attributed to K Sadamoto.

At least 55 records · Page 3Linked to original sources
PubMed1982

Minimum dose contrast bolus in computed angiotomography of the brain.

We have carried out basic investigations of an intravenous minimum dose bolus (MinDB) injection method for cerebral computed angiotomography by comparing blood iodine concentrations with high resolution computed tomography (CT) images of cerebral blood vessels. With the GECT/T 8800 scanner, a MinDB injection of 1 ml/kg of 60% Conray at a rate of 2 ml/s made it possible to increase the blood iodine concentration in the carotid artery to more than 15 mg/ml for about 20 s. Computed tomography performed during this period enabled us to obtain clear images of the circle of Willis, including other main cerebral arteries, deep veins, and cortical and lenticulostriate arteries. Cerebral computed angiotomography using this method should be useful for noninvasive screening or detection of cerebrovascular lesions themselves, such as cerebral aneurysms, cerebrovascular obstructions, arteriovenous malformations, and moyamoya disease, and should also be useful for determining the anatomical relationship between the cerebral blood vessels and other parenchymal or space occupying lesions.

Carotid Arteries↗
PubMed1982

Normal anatomy of cerebral vessels by computed angiotomography in the coronal, Towne, and semisagittal planes.

This report presents a detailed analysis of the normal cerebrovascular anatomy on the modified coronal, Towne (half-axial), and semisagittal computed tomographic (CT) images. Direct multiplane CT scans were obtained from fresh cadavers injected with gelatinous iodine solution. The modified coronal plane is optimal for delineation of the internal carotid bifurcations and the anterior and the middle cerebral arteries, and for identification of the lenticulostriate arteries and the angiographic sylvian point. The Towne plane is optimal for delineation of the vertebrobasilar arterial system. Thorough knowledge of the normal appearance of cerebral blood vessels in biplane or multiplane computed angiotomography is a prerequisite for understanding the spatial relationships of the abnormal cerebrovascular anatomy.

Basilar Artery↗
PubMed1982

Delineation of unruptured cerebral aneurysms by computerized angiotomography.

Unruptured aneurysms were diagnosed in 15 of 86 patients with cerebral aneurysms during 2 years beginning in April, 1979. One patient with severe head injury was excluded from the series. Fifteen aneurysms in the other 14 patients were first detected by computerized angiotomography. Six aneurysms were located in the middle cerebral artery, three in the upper half of the basilar artery, two in the anterior communicating artery, two in the posterior cerebral artery, and two at the internal carotid-posterior communicating artery junction (both in the same patient). Three were smaller than 5 mm, eight were between 6 and 10 mm, and four were larger than 10 mm. The noncontrast computerized tomography (CT) findings associated with 15 aneurysms were as follows: five showed defects in the basal cistern of Sylvian fissure, four were calcified or high-density masses, and in the six instances there was no evidence of an aneurysm. Unruptured aneurysms may be suggested by a well demarcated, round, isodense mass which forms a defect in the basal cistern of Sylvian fissure on a plain CT image, and are highly and homogeneously enhanced by computerized angiotomography. A carotid artery blood iodine level of 15 mg/ml is required to obtain clear images. The authors conclude that computerized angiotomography is useful in the delineation of unruptured aneurysms.

Adult↗
PubMed1982

[Multiplane postmortem cerebral computed angiotomography--Part I. Normal anatomy of cerebral vessels on the axial plane (author's transl)].

Cranial computed tomography has been mainly used for detection of the parenchymal space-occupying lesion, and has had the limitation of detection of the cerebrovascular lesion itself because of low CT resolution. However, high resolution CT scanners have recently brought us the possibility of definition of fine cerebral vessels on CT images using an appropriate injection method of contrast agents (cerebral computed angiotomography). This paper concerns the normal anatomy of the cerebral vasculature on CT images using 9 fresh cadavers with normal intracranial structures. They received the postmortem injection of contrast agents through bilateral common carotid and vertebral arteries, and were undertaken the multiplane CT scanning with the axial, modified coronal, Towne (half-axial) and the semisagittal projections using GE-CT/T 8800 (9.6 sec scanning time, 320 x 320 matrices). The normal anatomy of cerebral vessels on the axial plane, obtained at the levels 10 to 90 mm above the canthomeatal line, is presented in this paper. Main visualized vessels in the posterior fossa were the basilar artery, the cranial loop of the PICA, the AICA from the origin to the hemispheric branches including the meatal loop in the cerebellopontine angle cistern, and the SCA from the ambient and quadrigeminal segments to the lateral marginal and superior hemispheric branches. The circle of Willis and other main cerebral arteries were clearly visualized with their small branches, for example, the posterior communicating, the anterior choroidal and the lenticulostriate arteries. Deep cerebral veins were also visualized at the levels of the midbrain, the middle and the roof of third ventricle, and the body of lateral ventricle. Postmortem cerebral computed angiotomography provided us not only the precise anatomy of the cerebral vasculatures, but also their anatomic relations with the surrounding structures such as cerebral parenchyma, ventricles, cisterns and other subarachnoid spaces. On the clinical point of view, cerebral computed angiotomography can be applied to the screening system of vascular lesions themselves such as asymptomatic aneurysms, arteriovenous malformations, and Moyamoya disease.

Brain↗
PubMed1982

[Multiplane postmortem cerebral computed angiotomography--Part II. Normal anatomy of cerebral vessels on the modified coronal, Towne and semisagittal planes].

In order to obtain a detailed knowledge of the cerebral vasculature on computed tomographic (CT) images, multiplane CT scannings on the axial, coronal, Towne and sagittal planes are required. Previous reports have concerned only the axial CT images of the cerebral vasculature, and no mention has been made about the vasculature on the coronal, Towne or sagittal images. This paper concerns the normal anatomy of the cerebral vessels on the modified coronal, Towne (half-axial) and semisagittal CT planes using 9 fresh cadavers. They received postmortem injection of contrast agents and were scanned by GE-CT/T 8800 as mentioned in Part I. Scanning planes were the modified 50-60 degrees coronal, Towne (40-45 degrees off the canthomeatal line), and the semisagittal (45 degrees toward the sagittal plane). The main vascular structures visualized on the modified coronal CT plane resembled the antero-posterior view of the carotid angiogram, and they were as follows: internal carotid arteries (supra-clinoid portion), posterior communicating arteries, anterior choroidal arteries, anterior cerebral arteries (horizontal and ascending portions, pericallosal and callosomarginal arteries and other cortical branches), middle cerebral arteries (horizontal, insular, opercular and terminal portions with identification of the angiographic Sylvian point), lenticulostriate arteries, posterior cerebral arteries, basal vein of Rosenthal (BVR), internal cerebral veins (ICV), subependymal veins which drain into BVR and ICV, choroid veins, vein of Galen, and venous sinuses. As for the demonstration of the lenticulostriate arteries or the Moyamoya vessels in clinical cases, the modified coronal plane is preferred to the axial one. On Towne plane, the vertebro-basilar arteries and the ascending portion of anterior cerebral artery were demonstrated as linear densities, which were demonstrated as spotty densities on the axial plane. On the semisagittal plane, the median or paramedian vasculatures of the main cerebral arteries and deep cerebral veins, were well demonstrated like a lateral view of carotid angiogram. Biplane or multiplane cerebral computed angiotomography will increase in clinical diagnostic value for understanding the anatomical relationship between the cerebral vessels and other intracranial lesions, and also will be applied to the screening of small vascular lesions themselves, e.g., asymptomatic aneurysms, vascular occlusions, arteriovenous malformations and Moyamoya diseases.

Brain↗
PubMed1982

[Traumatic interhemispheric subdural hematoma--report of a case and analysis of 7 cases].

A case of traumatic interhemispheric subdural hematoma is reported and 7 cases, including ours, reported in literature are analyzed. A 43-year-old jogger hit his forehead in the traffic accident. After medical care for the wound at the near hospital, he walked to home without any neurological deficits. On the following day, he complained of headache, nausea and slight gait disturbance, so the visited us 5 days after head trauma. On the biplane computed tomograms, interhemispheric subdural hematoma was detected. A distinct avascular space in this portion was found on the right carotid angiograms. Treated conservatively with repeated computed tomography, he recovered completely well about a month after head trauma. Analyzing 7 cases, following comments were obtained; Age distribution was between 23 to 74 and all were male. The mechanism of the hematoma formation in such region remained still unclear, but seemed to be caused partially due to rotational cerebral injuries. Characteristic clinical symptom was hemiparesis, predominantly crural or crural monoparesis. This symptom was found in four of seven cases on the same side of the hematoma, that was supposed due to the compression of the contralateral blood flow the distal anterior cerebral artery. Neuroradiologically, on the angiograms, the internal branches of callosomarginal arteries turned away from the middle parallel to the pericallosal artery stayed in the middle and between them, a distinct avascular space was found. On the biplane computed tomograms, semilunar high density area was identified along the midline, bounded medially by the falx cerebri, laterally by the convex border against the brain parenchyma, inferiorly by the tentorium. Although the anteroposterior extension of the hematoma was recognized on the axial plane, the superoinferior extension, especially in relation to the tentorium, was well shown on the coronal plane. On the electroencephalogram, no characteristic findings were obtained. Abnormalities blood coagulation were found in a case. Five cases were operated on and 2 cases treated conservatively, and the outcome was good in all. The following diseases had to be differentiated: hematomas due to the rupture of peripheral anterior cerebral artery aneurysms, including traumatic ones, blood coagulopathy or medication of anticoagulants. Tumors such as parasagittal or falx meningiomas, subdural abscesses localized in the interhemisphere, infarctions of distal anterior cerebral artery.

Adult↗
PubMed1981

[Biplane computed cerebral angiotomography of moyamoya disease (author's transl)].

In this paper, the authors report biplane computed cerebral angiotomographic findings in 5 cases of Moyamoya disease. The specific features of Moyamoya disease on the CT image were as follows: On the axial plane, the linear structures of the anterior half of the circle of Willis and the proximal portion of the middle cerebral arteries disappeared, and instead of these normal structures, irregular, tortuous or patchy high-density areas just like a "caterpillar" were shown in the basal cistern and medial Sylvian fissures. On the modified coronal plane, the supraclinoid internal carotid arteries and the carotid fork could be identified only with a difficulty, and abnormal, "nebular" high-density areas consisting of irregular, tortuous or patchy high-density vascular components became visible in the basal cistern extending to the basal ganglia. A modified coronal plane and intravenous minimum dose bolus injection method seemed to be more useful for the visualization of these specific features on the CT image. Even before carotid angiography, we can suspect Moyamoya disease for finding these specific features on the CT image. Carotid angiography has been the only method of diagnosing Moyamoya disease. Instead of this invasive examination, computed cerebral angiotomography is useful in detecting Moyamoya disease conveniently and non-invasively. Therefore, we may conclude that computed cerebral angiotomography is very useful method for screening and follow up study of Moyamoya disease.

Adult↗