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S Tokiguchi

Publications and source records attributed to S Tokiguchi.

At least 37 records · Page 2Linked to original sources
PubMed1996

High-resolution CT findings in the development of the sphenooccipital synchondrosis.

PURPOSE: To evaluate the development of the sphenooccipital sychondrosis as seen on high-resolution thin-section CT scans. METHODS: We retrospectively reviewed the records of 253 patients, ages 1 to 77 years old, who had had thin-section CT examination of the skull base. RESULTS: An ossification center appeared midline in the patients who were 8 to 13 years old. Six of 12 girls showed additional symmetric ossification centers on either side of the midline; however, this pattern was not seen in boys. No sphenooccipital synchondrosis persisted in any patient past the age of 13 years. CONCLUSION: High-resolution CT scans of the skull base can show a pattern of progressive ossification of the sphenooccipital synchondrosis, which can be readily recognized and predicted.

Adolescent↗
PubMed1996

Atrophy of bilateral extraocular muscles. CT and clinical features of seven patients.

Swelling of the extraocular muscles is a common orbital abnormality that is easily demonstrated by computed tomography (CT). However, muscle atrophy is more difficult to identify and is rarely reported in the literature. Bilateral atrophy is extremely rare. We report the CT and clinical features of seven patients showing bilateral extraocular muscle atrophy: four with mitochondrial myopathy (MM) and three with myasthenia gravis (MG). Six patients had clinical histories of muscle involvement > 20 years. An incorrect diagnosis of MG was made initially in two patients with MM because of mildly positive Tensilon testing. The ocular motor abnormalities failed to improve after thymectomy in the myasthenic patients. Orbital appearance on neuroimaging is similar in these disorders. Differentiation between these two disorders is impossible with orbital CT and magnetic resonance imaging (MR) alone.

Adult↗
PubMed1995

Peculiar enlargement of the nasopharynx in patients with anorexia nervosa.

We examined the nasopharynx and brain in 17 patients with anorexia nervosa by CT and compared the findings with those of 44 normal subjects and of 5 patients of the same age with marked emaciation caused by various psychiatric disorders. An enlarged nasopharyngeal space with a flattened posterior wall and enlarged lateral pharyngeal recesses were demonstrated in all patients with anorexia nervosa whose weight was lowest at the time of the CT examination, and these CT features regressed or became normal quickly after they had gained some weight. This characteristic enlargement of the nasopharynx and lateral pharyngeal recesses was observed neither in the markedly emaciated patients (2 with schizophrenia, 1 with major depression, 1 with stupor and the other with an extremely unbalanced diet) nor in 44 normal subjects without emaciation. These features were therefore thought to be characteristic and of diagnostic significance.

Adolescent↗
PubMed1994

Corticobasal degeneration: etiopathological significance of the cytoskeletal alterations.

We have studied brain tissues from three patients with corticobasal degeneration (CBD) histologically, ultrastructurally and immunohistochemically. Ballooned neurons in the cerebral cortex and severe degeneration of the substantia nigra were observed in them all and weakly basophilic neurofibrillary tangles (NFTs) were distributed widely in the basal ganglia and brain stem. Ultrastructural examination demonstrated that the NFTs comprised characteristic 15-nm-wide straight tubules, which showed positive immunohistochemical staining with an antibody against tau, but not ubiquitin. Tau-immunoreactive neuronal cell bodies without NFTs also were found in the cerebral cortex and subcortical nuclei, predominantly in the brain stem, and the greatest number of tau-positive glial inclusions occurred in the cerebral gray and white matter of the pre- and post-central gyri. These inclusions comprised tubular structures with diameters of about 15 nm and were localized in the oligodendroglial cellular cytoplasm and processes. These findings indicate that there is a close cytoskeletal pathological relationship between CBD and progressive supranuclear palsy.

Aged↗
PubMed1993

CT of the pacchionian body.

The CT appearances of the pacchionian body, confirmed at autopsy, are reported. The pacchionian body appears as a low density mass in the dural venous sinus, of almost the same density as the subarachnoid space.

Aged↗
PubMed1992

Primary leptomeningeal glioma: ultrastructural and laminin immunohistochemical studies.

We studied a case of primary leptomeningeal glioma (PLG) on the left parietal lobe of a 74-year-old woman and compared the tissue with heterotopic glial tissue from another case. The PLG tumor consisted of spindle-shaped cells with marked nuclear atypism, which tended to be arranged in a fascicular pattern, and the majority of its cells were positive for glial fibrillary acidic protein. Ultrastructural examination demonstrated that most of the tumor cells contained intermediate filaments and often junctional complexes were present on their plasma membranes. Frequently, basal lamina-like structures surrounding the tumor cell surfaces were observed. Laminin immunohistochemistry clearly demonstrated a fine network of linear positive staining around the cytoplasm and processes of the tumor cells. The ultrastructure of the heterotopic glial tissue consisted of many astrocytes partially surrounded by basal lamina. These findings strongly suggest that PLG is a distinct tumor, which arises from the heterotopic astrocytes within the subarachnoid space.

Aged↗
PubMed1991

[Investigation of fat in the dural sinus].

Detection of fat in the cranium usually indicates the presence of a fat-containing tumor such as lipoma, dermoid cyst or teratoma. However, since 1982, Hasso et al demonstrated with CT the presence of normal adipose tissue in the cavernous sinus, the mere existence of fat in the cranium does not necessarily mean the presence of a fatty tumor. The author first described fat deposition in the superior sagittal sinus and torcular Herophili following a CT study performed in 1986. The purpose of this study was to investigate the distribution, frequency, and anatomical correlations of fat in the dural sinus as demonstrated on CT. Fat was detected in the cavernous sinus in 20% of all cases (492/2408), and occurred more frequently (25%) in those older than 50 years. Fat was less frequent in the other dural sinuses (3%; 75/2296). The most common location was the torcular Herophili, followed in decreasing order of frequency by the straight sinus, inferior sagittal sinus, superior sagittal sinus and transverse sinus. Pathological examination was performed in three cases. Fat deposition was composed of normal adipose tissue and was devoid of fibrous encapsulation or infiltration. In one case, the fat seemed to be partly exposed to the subarachnoid space on CT, whereas on autopsy, thin dura mater covering the fat nodule was confirmed. Fat in the dural sinus must be differentiated from cavernous nodule or sinus thrombosis. The Hounsfield unit may be helpful in making a definitive diagnosis.

Adipose Tissue↗
PubMed1991

An autopsy case of atypical motor neuron disease with Bunina bodies in the lower motor and subthalamic neurons.

We report a 37-year-old male without any family history of neurological disease who suffered progressive muscular atrophy and sensory impairment of 4 years' duration. Autopsy revealed neuronal loss in the anterior horns of the spinal cord and in the hypoglossal and facial nuclei of the brain stem. The corticospinal tracts of the spinal cord showed only mild degeneration. In addition, there were obvious degenerative lesions manifested by loss of neurons, myelin and axons in the spinal posterior columns, Clarke's column, spinocerebellar tracts and dorsal root ganglia as well as in the subthalamic nucleus, globus pallidus, substantia nigra and cerebellar dentate nucleus. Furthermore, we frequently encountered Bunina bodies not only in the lower motor neurons but also in the subthalamic neurons. We consider this case to be an atypical example of motor neuron disease with features of multisystem degeneration. The fact that Bunina bodies were observed in both lower motor and subthalamic neurons in this case suggests a common etiology of neuronal degeneration in these two different systems.

Adult↗
PubMed1990

[The MR findings on the corpus callosum of normal young volunteers].

The size and shape of the corpus callosum of twenty-seven normal young volunteers (age 18-31 years, 17 men and 10 women) were investigated using a superconducting high field (1.5 T) MRI unit. The length of the corpus callosum was 71.1 +/- 5.1 mm (mean +/- S.D.) and the height was 24.9 +/- 2.1 mm. The length ratio of the corpus callosum to the brain was 43.9 +/- 2.3% with the ratio of the height 25.0 +/- 2.3%. The callosal index (height/length) was 35.4 +/- 2.9%. The area of the corpus callosum in the midsagittal plane was 681.4 +/- 93.6 mm2 (min. 563 mm2 to max. 902 mm2). We divided the corpus callosum into three segments: rostrum and genu; anterior and posterior trunks; splenium. Each part accounts for one third of the total area of the corpus callosum. The genu and splenium were generally equal in thickness. The minimal thickness of the trunk was 3 mm with the maximal one 9 mm. The posterior trunk was never thicker than the anterior one. The posterior part of the posterior trunk showed thinning and concavity in almost all cases. So-called impressio corporis callosi was observed in 12 cases (44.4%). Thirteen cases (48.1%) showed a shallow concave configuration at the anterior dorsal surface of the corpus callosum. Six cases of these were thought to be due to compression by the pericallosal artery. This finding was not detected in the posterior portion of the corpus callosum. This concavity was also seen in infants. The thinning of the posterior part of the posterior trunk was seen after the development of the splenium, but the concave configuration at the anterior dorsal surface of the corpus callosum may be encountered before the full development of the genu and splenium.

Adult↗
PubMed1990

[Convulsive seizures and heterotopic gray matter; report of two cases].

We reported CT and MRI findings of heterotopic gray matter in two patients with intractable convulsive seizures. CT demonstrated space-occupying but non-expansive lesions isodense with the cortical gray matter adjacent to the body of the lateral ventricle. These lesions were not enhanced with contrast infusion. MRI was performed in one case in which the lesion was isointense with the cortical gray matter.

Brain Neoplasms↗
PubMed1990

[A case of xanthoma of the skull].

The reports in the radiologic literature of osseous xanthoma are very rare. We reported a case of xanthoma of the skull without hyperlipidemia. The bony changes is well-marginated radiolucent lesion with marginal sclerosis and an central nidus of bone.

Bone Diseases↗
PubMed1988

Fat in the dural sinus--CT and anatomical correlations.

Two cases of fat in midline dural sinuses, detected by high-resolution CT, were studied anatomically. The fat nodules were not located in the sinus lumen, but in the sinus wall. They were composed of normal adipose tissue without fibrous encapsulation. Our findings have proved that the fat deposit as demonstrated by CT within these dural sinuses represents normal adipose tissue in the sinus wall and does not necessarily mean the presence of a fatty tumor.

Adipose Tissue↗
PubMed1986

Fat in the dural sinus.

Fat density in the dural sinus on computed tomography (CT) is described in eight cases. Of the eight cases, five had fat deposit in the torcular Herophili, and three in the superior sagittal sinus. This finding was incidentally found by CT and there was no common underlying disease in these cases. It is suggested that this finding represents normal adipose tissue in the dural sinus.

Adipose Tissue↗
PubMed1980

Myoclonus epilepsy associated with ragged-red fibres (mitochondrial abnormalities ): disease entity or a syndrome? Light-and electron-microscopic studies of two cases and review of literature.

A report is given of an association of dyssynergia cerebellaris myoclonica associated with Friedreich's ataxia and mitochondrial myopathy in 2 patients. They had suffered from gradually increasing bursts of myoclonus since the wage of 14 and childhood, respectively. The other striking clinical features included generalized convulsions, mental deterioration, intention tremor, ataxia, muscular atrophy and deformity of feet. Muscle biopsies revealed ragged-red fibres in both cases. On electron microscopy these fibres contained subsarcolemnal aggregations of abundant abnormal mitochondria with proliferation of inner membranes or paracrystalline inclusions. One of these patients showed elevated blood lactate and pyruvate with an increased lactate/pyruvate ration, apparently of primary origin. These 2 cases resemble those reported briefly by Tsairis et al. (1974). An association of dyssynergia cerebellaris myoclonica associated with Friedreich's ataxia and mitochondrial myopathy in these 2 patients is unlikely to be coincidental but may represent one nosological entity. This myoclonus epilepsy syndrome associated with ragged-red fibres is compared with other possibly related mitochondrial encephalomyopathies.

Adult↗