Search PubMed⌕ Search

Biomedical subjects

S Asari

Publications and source records attributed to S Asari.

At least 163 records · Page 9Linked to original sources
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↗
PubMed1982

[An interesting case of the traumatic middle meningeal arteriovenous fistula].

The authors reported an interesting case of the traumatic middle meningeal arteriovenous fistula which was caused by the minor head injury on the opposite side complicated with a subarachnoid hematoma, and was completely cured 35 days after head injury without any surgical intervention. A 75-year-old woman fell down after unconsciousness fit and hit her right head, then visited Matsuyama Shimin Hospital complaining of nausea, vomiting and severe left temporalgia. Neurologically, no other abnormalities were found. On plain skull roentogenograms, a linear fracture was noted on the right temporal bone, but not on the left side. A subarachnoid hematoma localized in the left Sylvian fissure was identified on plain computed tomograms. Left carotid angiograms revealed the middle meningeal arteriovenous fistula at the left middle fossa, which showed an characteristic drainages, i.e. mainly draining to the pterygoid venous plexus and the superior sagittal sinus, partially to the cavernous sinus. She was admitted to our ward and was treated only conservatively. Thirty-five days after head injury, her complaints improved remarkably and left carotid angiograms, performed on the next day, disclosed complete disappearance of the previous fistula, and suggested the point of fistula clearly. Documenting the computed tomogram and the angiograms of our case, possible mechanism of fistula formation and its spontaneous cure was discussed. The middle meningeal arteriovenous fistula was formed by the interaction between the direct or indirect influence of head injury and anatomical, histological and pathological factors of meningeal vessels themselves. Spontaneous cure of the fistula resulted from thrombosis at the point of fistula. In our case, irregularity of the wall of anterior middle meningeal artery on the repeated angiograms supported this view.

Aged↗
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↗
PubMed1980

Increase of peripheral B lymphocytes in Graves' disease.

Peripheral T and B lymphocytes were examined in autoimmune thyroid diseases. The percentages of T and B lymphocytes were calculated from the proportions of E and EAC rosette-forming cells and peroxidase-positive cells determined by micromethods. In thyrotoxic Graves' disease, the percentage of T cells was significantly lower, and the percentage of B cells was higher than in normal controls. The absolute count of B lymphocytes was also markedly increased. The serum levels of thyroid hormones showed a significant correlation with the percentage of B cells and an inverse correlation with that of T cells in untreated cases of Graves' disease. Similar abnormalities of lymphocyte subpopulations were observed in patients with thyrotoxic Graves' disease under drug therapy, but the proportions and absolute counts of T and B lymphocytes were normal in euthyroid patients with Graves' disease, either under drug therapy or in remission. No abnormalities in T and B cells were found in Hashimoto's disease. The data indicate that the main feature of the abnormality of the lymphocyte subpopulations in thyrotoxic Graves' disease is an increase of B lymphocytes. The reasons for the discrepancy between our results and those of earlier reports and for the B cell abnormality in Graves' disease are discussed.

Adult↗
PubMed1977

[Effect of extracranial-intracranial vascular bypass formation on experimental cerebral infarction in dogs (author's transl)].

The middle cerebral artery was occluded at its origin via subtemporal approach by microsurgical technique in 24 dogs. In 8 of these 24 dogs, end-to-side anastomosis between the maxillary artery and a branch of the middle cerebral artery (MA-MCA anastomosis) was made 4 hours after MCA occlusion. In 5 dogs, MA-MCA anastomosis was performed under microscopic control 3 weeks after MCA occlusion. Remaining 11 dogs without shunt operation were used as control animals. All the animals were clinically observed every day until sacrifice. In the control animals, common carotid angiography was performed between the 2nd and the 5th postoperative weeks. The treated animals were studied by selective external carotid angiography 2 weeks after MA-MCA anastomosis. After sacrifice, transcarotid perfusion with 10% formalin solution was carried out and the brain was carefully removed. Each brain was additionally fixed in 10% formalin, sectioned, stained and examined pathologically. Clinical evaluation in all the control animals showed mild to severe neurological deficits or death. On the other hand, the animals with patent bypass in acute stage demonstrated no neurological deficits. Gross and microscopic evaluation of the brains showed that the permanent occlusion produced a medium or large-sized infarct in the occluded MCA territory, and the patent prompt bypass usually caused no or only microscopic infarct. In the patent delayed bypass, the size of infarct seemed smaller than that in the untreated animals. No hemorrhagic infarct was found in treated animals with either prompt or delayed bypass. In general, it seemed that the animals with patent bypass fared better than untreated animals both clinically and pathologically. The experimental data suggest that reestablishment of blood flow by extra-intracranial anastomosis, particularly within 4 hours after MCA occlusion, may lead to a significant restoration of neurological function without pathological damage of the brain.

Animals↗
PubMed1976

[Maxillary artery to middle cerebral artery anastomosis in dog-- a new experimental model (author's transl)].

End-to-side anastomosis between the maxillary artery and a branch of the middle cerebral artery was performed in the dog. The technique was devised as a new experimental model for extracranial-intracranial arterial shunt operation. The middle cerebral artery was ligated at the origin through a subtemporal small burr hole under the operating microscope in 13 dogs. Then, the shunt operation was carried out in 8 dogs 4 hours after the ligation(acute state), and in 5 dogs 3 weeks after(chronic stage). The patency of the anastomotic site was evaluated by the selective external carotid angiography 2 weeks after the shunt operation. In the acute stage of 8 dogs, 7 cases showed patency of anastomosis (88%), and in the chronic stage of 5 dogs, arteriogram revealed 4 patent anastomosis (80%). In successful cases, arteriogram showed excellent filling of the entire territory of the middle cerebral artery through the shunts (Fig. 4, 5). Various types of experimental shunt operation were attempted in our review of the literature. Among them, the anastomosis between the superficial temporal artery and a branch of the middle cerebral artery by Yasargil (1967) is rather popular and this procedure has been used by some investigators including us to investigate the effect of the extracranial-intracranial shunt on experimental acute stroke. So far as dog's experiment is concerned, the superficial temporal artery appeared to be not suitable for a donor artery, because the superficial temporal artery runs far from the middle cerebral artery and its distal part is extremely small in caliber. Therefore, the superficial temporal artery was often obstructed by compression, kinking or narrowing by surrounding tissues and by adhesion to the bone edge of the burr hole. On the other hand, the maxillary artery of the dog, which is the largest terminal branch of the external carotid artery, has plenty of blood flow and suitable size for end-to-side anastomosis to the middle cerebral artery. In addition, maxillary artery is located very close to the proximal part of the middle cerebral artery. These anatomical and spatial advantage of the maxillary artery seemed to be favorable donor artery to the middle cerebral artery and have brought hight patency rate in our series of anastomosis than that of the other previous experimental extracranial-intracranial shunts. To our knowledge, this is the first report on successful patent shunt formation after long-term occlusion of the middle cerebral artery in animals. Now, it is in our mind that progress of the study can be expected in the field of extracranial-intracranial shunt operation for cerebral infarction by this experimental procedure.

Animals↗
PubMed1976

[Traumatic aneurysm of the peripheral cerebral artery].

Two cases of traumatic aneurysm of peripheral cerebral artery were reported. Case 1. A 6-year-old girl was severely injured on her head by automobile accident. Plain skull films showed depressed fracture in the left frontal region. Left common carotid angiogram 25 days after the injury revealed small aneurysm of a cortical branch of the anterior cerebral artery. Cranioplasty and removal of the aneurysm was performed. Postoperative course of this patient was uneventful. Case 2. A 4-year-old girl fell downstaris and struck her left temporal region. On admission, she was unconscious and plain skull films showed multiple linear fractures. No aneurysm was demonstrated in the right common carotid angiogram immediately after the head trauma. Since her general condition gradually improved, she discharged 23 days after the head trauma. 63 days after the injury, she developed sudden onset of severe headache, vomiting, and status epilepticus. Right common carotid angiogram showed a large aneurysm arising from a branch of right pericallosal artery at the free edge of the falx. Parent artery of the aneurysm was clipped. Postoperatively, the patient made uneventful recovery. 60 reported cases of traumatic aneurysm of peripheral cerebral artery were reviewed and analyzed in etiology, diagnosis, clinical course, treatment and pathogenesis.

Brain Injuries↗