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M Shigemori

Publications and source records attributed to M Shigemori.

At least 91 records · Page 5Linked to original sources
PubMed1994

[Two cases of distal superior cerebellar artery aneurysm].

Two cases of subarachnoid hemorrhage due to a ruptured aneurysm of the distal superior cerebellar artery (SCA) are reported. In the first case the patient was a 78-year-old woman who complained of severe headaches and was admitted to a local hospital on May 25, 1992. A CT scan revealed a subarachnoid hemorrhage, and an angiogram showed an aneurysm of the right ambient segment of the superior cerebellar artery. Trapping of the aneurysm was successfully performed via a subtemporal approach on June 9, 1992. In the second case the patient was a 46-year-old man who complained of severe headaches and was admitted to Kurume University Hospital. A CT scan showed subarachnoid hemorrhage and an angiogram showed an aneurysm of the right ambient segment of superior cerebellar artery. Trapping of the aneurysm was successfully performed via a subtemporal approach on Sept 11, 1990. Forty-three reported cases of distal SCA aneurysm were reviewed. Only one patient received early surgical treatment, and with surgery in all of the other cases being delayed. Both of our patients underwent delayed surgical treatment with excellent results. The clinical characteristics of distal SCA aneurysms and the timing of surgery are discussed.

Aged↗
PubMed1994

[Effect of nitric oxide on central dopaminergic neurons].

Neuronal damage induced by ischemia involves various changes in neurotransmission. Nitric oxide (NO), a putative neurotransmitter and/or neuromodulator has some role in this neuronal damage. In the present study, the effect of NO on the terminal site of dopamine (DA) neurons in the rat striatum was examined using the microdialysis technique. First perfusion with sodium nitroprusside (SNP) as an NO donor increased extracellular DA (10 mM, 460%; 1 mM, 140%) in the striatum and decreased its metabolites. Pretreatment with tetrodotoxin (TTX, 5 microM), (+)-5-methyl-10,11-dihydro-5H-dibenzo [a,d] cyclohepten-5,10-imine hydrogen maleato (MK801, 1 microM) or muscimol (1 microM) inhibited SNP-induced increases in extracellular DA and decreases in DOPAC (TTX, complete block; MK801, 75% inhibition; muscimol, 80% inhibition). Second, extracellular NO, DA and DOPAC were measured in the gerbil striatum following 10 minutes of forebrain ischemia produced by occluding both carotid arteries. Occlusion of the carotid arteries also caused increases in extracellular NO and DA in the gerbil striatum (NO, 3000%; DA, 2800%). These findings suggest that NO-facilitated DA release occurs via interaction between glutamatergic and dopaminergic neurons. These changes are probably partially involved in the neurodegenerative phenomena following ischemia. It is also shown that simultaneous measurements of NO and DA using this technique may be useful in assessing ischemic changes in vivo.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1994

[A case of convexity arachnoid cyst associated with chronic subdural hematoma and intracystic hemorrhage].

Arachnoid cysts account for about 1% of all intracranial tumors, in which about 50% arise from the middle cranial fossa, and rarely occur at the cerebral convexity. They sometimes are associated with chronic subdural hematoma (CSDH) but the exact mechanism of their development is still unclear. A 15-year-old boy was admitted to our hospital with an arachnoid cyst at the right frontal convexity. When he experienced recurrent generalized seizure, CT and MRI revealed CSDH localized at the surface of the arachnoid cyst. Radical operation for the cyst with CSDH was successfully performed. As far as we know, it is rare that CSDH and hematoma are colocalized over an arachnoid cyst at the cerebral convexity. In this report, the operative findings of this patient and possible mechanism of CSDH formation were reported.

Adolescent↗
PubMed1993

Completely thrombosed giant fusiform aneurysm in a young patient--case report.

A completely thrombosed giant fusiform aneurysm of the peripheral anterior cerebral artery occurred in a 16-year-old female, with a familial and personal history of vascular headache for 4 or 5 years. She was admitted in a drowsy state with severe headache. Computed tomography revealed subarachnoid hemorrhage and intracerebral hemorrhage as a mottled and ring-like high-density area in the left paramedian frontal lobe not enhanced postcontrast. Left carotid angiography demonstrated an avascular mass and a 5 cm defect in the A3 portion of the anterior cerebral artery. The rupture of the giant fusiform aneurysm was confirmed intraoperatively.

Adolescent↗
PubMed1993

Scanning electron microscopic observations of the arachnoid granulations in monkeys with cerebrospinal fluid hypotension.

The changes in arachnoid granulations following the depletion of cerebrospinal fluid (CSF) were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In the normal tissue, the arachnoid granulations located at the inner walls of the superior sagittal sinus and the straight sinus had bulging protrusions of various sizes, as viewed with the SEM. With TEM, the outermost cells covering the surface of the arachnoid granulations had "giant vacuoles" in the cytoplasm. With CSF hypotension, the arachnoid granulations were smaller in size and the outermost layer of cells were thinner. The vacuoles in the outer layer were not developed. In the apical region of the individual arachnoid granulations with CSF hypotension, the arachnoid cells were densely clustered under the endothelial cells. With recovery to normal CSF pressure, the arachnoid cells appeared to protrude between the endothelial cells covering the apical portion of the arachnoid granulation.

Animals↗
PubMed1993

[A case of Turcot syndrome (glioma polyposis)].

We reported a case of Turcot Syndrome (glioma polyposis) in a 19-year-old woman with nonfamilial polyposis coli and adenocarcinoma of the colon, and grade 3 astrocytoma in the right parietal lobe. The patient was admitted with the complaint of general convulsion after colostomy for polyposis and adenocarcinoma of the colon. CT scans on admission showed a large parietal tumor in the right side. Total removal was performed successfully and histological examination showed astrocytoma grade 3. One year after the operation, the tumor recurred. Conservative treatment failed to improve her condition and she died one year later. Turcot Syndrome (glioma polyposis) is very rare and only 10 cases have been reported in Japan. In this report, the clinical characteristics of this syndrome were discussed.

Adenocarcinoma↗
PubMed1992

Coexisting diffuse axonal injury (DAI) and outcome of severe head injury.

The importance of coexisting diffuse axonal injury (DAI) and outcome were studied in 107 patients with diffuse and focal brain injury. Comprehensive neuropathological study was undertaken in 26 fatal patients. There was a clear rank order of the mortality rate in the lesion type. The rank order of good recovery and moderate disability was also similar to the inverse of the mortality ranking. The pathological "marker" of DAI, macroscopic lesions in the corpus callosum and dorsolateral quadrant of the upper brainstem and histological evidence of axonal retraction balls, were commonly found not only in patients with diffuse brain injury but also in focal brain injury. The type of intracranial lesion in severe head injury is thus an important factor in determining outcomes and DAI of varying severity is the common subjacent lesion in the fatal patients.

Adolescent↗
PubMed1992

Monitoring of severe head-injured patients with transcranial Doppler (TCD) ultrasonography.

Intracranial haemodynamics were studied in 36 patients with severe head injury and experimental animals with acute intracranial hypertension by the use of TCD ultrasound. The mean flow velocity (FV) in the basal cerebral arteries commonly decreased on the side of the haematoma depending on intracranial pressure (ICP) elevation and cerebral perfusion pressure (CPP) reduction in focal brain injury. The FV decreased bilaterally and there was no difference between the right and left sides in diffuse brain injury without a clear relationship between the FV and CPP. The FV of the middle cerebral artery and blood flow in the internal carotid artery exhibited flow patterns which changed correlatively depending on CPP reduction in experimental animals. Monitoring with TCD ultrasound is valuable in evaluating compression ischaemia in focal brain injury. But many complicated factors are considerable in diffuse brain injury.

Adolescent↗
PubMed1992

[Quantitative analyses of the normal throat flora of children with upper respiratory tract infections].

Relationship between the normal throat flora and pathogenic bacteria recovered from the throat in 139 children with upper respiratory tract infections in winter were studied using quantitative analyses. Pathogenic bacteria examined include S. pyogenes, H. influenzae, S. aureus, and S. pneumoniae, and the normal floras include alpha-streptococci, gamma-streptococci, Neisseria species, and Micrococci. Children with S. pyogenes in their throats (S. pyogenes group) were examined with anti-streptococcal antibodies such as anti-streptolysin O, anti-streptokinase, and anti-deoxyribonuclease B. Eighty seven pathogenic bacteria were recovered from 72 children (51.8%) out of 139. S. pyogenes and S. pneumoniae groups showed significantly lower alpha-streptococci and gamma-streptococci in incidence of appearance when compared with children with the no pathogenic bacteria in their throats (no bacteria group). H. influenzae group showed significantly lower gamma-streptococci and higher Neisseria sp. in incidence of appearance compared with the no bacteria group. Positive cases for anti-streptococcal antibodies showed a significantly lower alpha-streptococci in number compared with negative cases for antibodies and the no bacteria group, and a significantly lower gamma-streptococci in incidence of appearance compared with the no bacteria group. These data suggest that the normal throat flora may have a role in prevention of colonization by the pathogenic bacteria in vivo, as were shown in vitro by many authors, and that the quantitative analysis of the normal flora is useful because this methodology might reveal whether the bacteria recovered from the throat show the pathogenicity.

Adolescent↗
PubMed1992

Radiation-induced osteosarcoma of the calvaria--case report.

The authors report a case of radiation-induced calvarial osteosarcoma. A 58-year-old female received subtotal removal of the pituitary adenoma and 5000 rads postoperative irradiation. Seven years later, an osteoblastic osteosarcoma occurred in the frontotemporal region. She received total tumor removal and chemotherapy. However, computed tomography subsequently revealed multiple small lesions at the margin of the bone flap. A chest x-ray film demonstrated lung metastasis. Local recurrence and lung metastasis require careful attention in radiation-induced osteosarcoma patients.

Adenoma↗
PubMed1992

Contralateral development of acute subdural hematoma following surgery for chronic subdural hematoma--case report.

An unusual case of acute subdural hematoma developed after drainage of chronic subdural hematoma in a 71-year-old male. The acute subdural hematoma was located over a membranous layer in the subdural space similar to the outer membrane of the chronic subdural hematoma. Intraoperatively, bleeding from the bridging vein and oozing from the superior sagittal sinus were observed. The membranous layer probably separated from the dura mater following decompression after drainage of the contralateral hematoma, and this separation then damaged the bridging vein and superior sagittal sinus, resulting in the acute subdural hematoma.

Acute Disease↗
PubMed1992

[Emergency manual aspiration for severe hypertensive cerebellar hemorrhage].

We treated 16 patients with hypertensive cerebellar hemorrhage and coma, or deep coma. Their ages ranged from 44 to 79 years (mean age: 66.3 years). Manual aspiration was performed in 9 patients and suboccipital craniectomy was performed in 7 patients. The difference in outcome between the manual aspiration group and the suboccipital craniectomy group with severe hypertensive cerebellar hemorrhage was then evaluated. Manual aspiration was performed for 4 patients in coma, and 5 in deep coma, with a mean age of 69.0 years. The average size of the hematoma was 48.7mm and the mean volume was 31. 7ml on CT scan. The mean interval from admission to operation was about 60 minutes. The mean aspiration rate was 79.6% and 7 patients (77.8%) had a good response to drainage. The suboccipital craniectomy patients included 5 in coma, and 2 in deep coma, with a mean age of 63.4 years. The average size of the hematoma was 51.1 mm and the mean volume was 33.1 ml on CT scan. The mean interval from admission to operation was about 112 minutes and the mean evacuation rate was 86.4%. The results were as follows: 1) After manual aspiration, 5 patients (55.6%) had a good outcome and 2 patients (40%) with deep coma showed good recovery. In contrast, after suboccipital craniectomy only 2 patients (28.6%) had a good outcome and all of the deep coma patients showed poor recovery. 2) The outcome may be most strongly influenced by the duration from admission to operation. 3) All patients with a hematoma volume of over 30 ml had a poor outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[Acute subdural hematoma caused by mild head trauma in the aged].

We encountered 8 cases of acute subdural hematoma caused by mild head trauma in the aged. In this report, these cases were analyzed, taking into consideration clinical symptoms, CT scan, operative findings and outcome. The age ranged from 70 to 92 years (mean age of 79.7 years). 4 patients were male and 4 female. Head trauma was caused by falls in 4 patients, but in the other 4 patients the causes were unknown. Initial symptoms were headache, nausea and vomiting in 5 patients and mild disturbance of consciousness with lucid intervals in 3 patients. Seven patients had more than 100 on JCS and less than 9 on GCS on admission. Small craniotomy (HITT) was performed in 4 patients. Large craniotomy was performed in 2 patients, and decompressive craniectomy was carried out in 2 patients. The bleeding focus came from the cortical artery of the middle cerebral artery in 4 patients, cerebral contusion in 2 patients, and was unknown in 2 patients for HITT. CT scan on admission showed mixed density area of acute subdural hematoma in all of the patients, and intraventricular hemorrhage, intracerebral hemorrhage and subarachnoid hemorrhage in 3 patients. CT scan after operation revealed a new area of cerebral contusion in 3 patients, delayed traumatic intracerebral hematoma (DTICH) in 2 patients, and hypertensive intracerebral hemorrhage in 1 patient. Two patients recovered to good and fair without general complication. But the outcome in 5 patients with general complication was poor for 3 patients and fatal for 2 patients. In conclusion, large craniotomy is recommended because of bleeding from the cortical artery of the middle cerebral artery.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1992

[Multiple intracranial aneurysms following radiation therapy for pituitary adenoma; a case report].

A report is made here on a rare case in which occurrence of multiple cerebral aneurysm was observed after radiotherapy. The case was that of a female aged 51 who was hospitalized with the chief complaint of consciousness disorder. The patient was discharged from the hospital 1 year before, after undergoing subtotal extirpation of a tumor through the transsphenoidal sinus in a case of pituitary adenoma, and post-operative radiotherapy (topical 50 Gy). Mild hyperlipidemia associated with hypothyroidism was observed by blood biochemical test during the patient's hospitalization, and multiple cerebral infarction was also observed by CT scanning and MR imaging. Therefore, conservative treatments including intensified endocrine-supplementing treatment, centering on thyroid hormone, were attempted. The patient's thyroid gland function and hyperlipidemia improved but the consciousness disorder persisted. Exacerbation of the consciousness disorder occurred suddenly 6 weeks after the patient's hospitalization. Subarachnoid hemorrhage and hydrocephalus were observed by CT scanning. Cerebral angiography detected a saccular aneurysm in the trifurcation of the right middle cerebral artery, 3 fusiform aneurysms in the periphery of the right middle cerebral artery, 2 fusiform aneurysms in the posterior cerebral artery and irregularity of wall width in the central artery including the terminal region of the internal carotid artery. These findings were not observed at the initial hospitalization and were considered to have been formed newly afterwards. Further, these findings were observed unexceptionally in all the radiated fields. The patient died 8 weeks after hospitalization, and no autopsy finding was obtained. From the above, we presumed that radiation vasculopathy caused by the radiation therapy made one year previously, had led to the formation of multiple cerebral aneurysms.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗
PubMed1992

[Significance of the cerebral venous system in the development of DIND in subarachnoid hemorrhage].

The significance of superficial venous system in the development of delayed ischemic neurological deficit (DIND) was studied retrospectively in 18 patients with ruptured aneurysm of the middle cerebral artery (MCA). Neck clipping of the aneurysms was performed via the pterional approach within 72 hours after onset of subarachnoid hemorrhage. All patients were in grade I or II of the Hunt and Hess Grading, and in group 2 or 3 on Fisher's CT classification. The age ranged from 32 to 71 with 48.1% being the mean age. The aneurysm was located on the left side in 5 patients, and on the right side in 13 patients. Arterial and venous phase were evaluated on the pre-and post operative angiograms in these patients. Arterial narrowing was divided into localized and diffuse types according to the degree, and its distribution in the arterial tree. In the venogram, opacification of the superficial sylvian veins (SSV) was the main thing evaluated. Arterial narrowing was observed in 16 cases (9; localized, 7; diffuse). In some cases, visualization of the SSV was poor or fair, and in others it was normal. DIND, including motor deficit or disturbance of consciousness, developed in 10 cases (transient; 6, permanent; 4). The patients with normal visualization of SSV on the postoperative angiogram had good outcome, even if they had diffuse arterial narrowing. On the other hand, the outcome was only fair or poor in those patients who had poor visualization of the SSV, irrespective of arterial narrowing.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗