Prevention of symptomatic vasospasm by continuous cisternal irrigation with mock-CSF containing ascorbic acid and Mg(2+).

BACKGROUND: Symptomatic vasospasm (SVS) is still a major cause of poor outcome in cases undergoing early surgical intervention for ruptured intracranial aneurysm. Among the numbers of therapeutic trials to prevent and ameliorate neurological deterioration due to SVS, removal or quenching of oxy-hemoglobin (OxyHb) from subarachnoid colts and administration of Mg(2+) (Mg) have especially been expected to be effective. In this report the authors investigated the effect of continuous cisternal irrigation (CCI) with mock CSF containing ascorbic acid (ASA) and Mg, performed after early surgery for ruptured aneurysm. METHOD: Sixty-three cases which had received CCI were retrospectively compared with 40 control cases as to the incidence of SVS and outcome. FINDINGS: Incidence of SVS was significantly less frequent (P < 0.05) in the CCI group (11%) than in the control group (25%). Severe and definitive SVS requiring additional specific treatment occurred only in 3.2% of the CCI group, while 22.5% in the control (P < 0.01). Overall outcome at discharge was significantly better in the CCI group than in the control (P < 0.01). CONCLUSIONS: Postoperative CCI with ASA and Mg was definitively effective in preventing SVS and in lessening severity of SVS if it occurs.

[Case of conduction aphasia due to right hemispheric lesion].

We report the case of conduction aphasia due to injury of the right hemisphere of the brain. The patient was a right-handed male in his fifties with moyamoya disease. T2-weighted MRI showed an extensive high intensity area in the right temporal-parietal-occipital lobes. In the case of language-related symptoms, comprehension was preserved, but phonemic paraphasias were frequent, and kana paragraphias were also observed. Despite the extensive injury of the right hemisphere, these language-related symptoms were consistent with the clinical features of conduction aphasia. Therefore, this patient was diagnosed with atypical crossed aphasia. Improvement in the phonemic paraphasia differed between words and nonsense words, suggesting that the improvement was dependent on the level of meaning of the words.

Common carotid artery stenosis and amaurosis fugax.

BACKGROUND: Clinical characteristics of common carotid artery (CCA) stenosis have been reported relatively rarely, compared with those of internal carotid artery (ICA) stenosis. The current retrospective study aimed to clarify the symptomatology of CCA stenosis. METHODS: Summarized records of patients admitted were reviewed to identify patients with CCA stenosis or extracranial ICA stenosis. Clinical histories and neurologic symptoms were identified and analyzed. RESULTS: CCA stenosis was present in 12 patients (symptomatic, n = 8; asymptomatic, n = 4). Among symptomatic patients, 4 (50%) had amaurosis fugax. Among 137 patients with symptomatic extracranial ICA stenosis, amaurosis fugax occurred in 9 patients (6.6%). CONCLUSIONS: Frequency of amaurosis fugax was significantly higher in CCA stenosis than in ICA stenosis. Patients with CCA stenosis may be susceptible to transient hemodynamic insufficiency of the retina as a result of simultaneous reductions in blood supplies from both the external carotid artery and the ICA.

[Chronological changes in MR angiography of a case with isolated angiitis of the CNS].

Isolated angiitis of the central nervous system (IAC) is a disease of unknown etiology, and is restricted to the small-to-medium-sized blood vessels of the central nervous system. We report serial MR angiography findings in a case of IAC. A 51-year-old female came to our hospital because of severe headache. Computed tomography (CT) 6 days after the onset didn't show anything particular, and MR angiography 8 days after the onset revealed segmental stenosis of the bilateral anterior cerebral arteries. However, we couldn't diagnose it as IAC. Thirteen days after the onset, the patient's headache worsened. Subsequent MRA revealed severe stenosis of the bilateral anterior and middle cerebral arteries. After that, steroid therapy was initiated. Her headache was disappeared immediately. Twenty-nine days after the onset, MRA showed the improvement of stenosis. Seventy-three days after the onset, stenosis of the cerebral arteries was disappeared. Interestingly, in another case report of IAC, MRA showed improvement of the stenosis one month after the onset, and disappearance of the stenosis two months after the onset.

Neuroprotective efficacy of selective brain hypothermia induced by a novel external cooling device on permanent cerebral ischemia in rats.

OBJECTIVES: This study was aimed at examining whether hypothermia is neuroprotective against permanent cerebral ischemia in rats. METHODS: A total of 32 male Sprague--Dawley rats were subjected to a middle cerebral artery occlusion. In the hypothermic group, rats (n=10) underwent selective brain hypothermia for 5 hours with the use of a novel surface coil with coolant circulating inside. In the control (n=13) and sham groups (n=9), the rats were maintained at normothermia. After a period of 168 hours ischemia, animals were killed to measure the infarction volume of the brain stained with hematoxylin-eosin. RESULTS: There were no significant differences in physiological parameters except for the temperature. The present style of hypothermia significantly reduced infarction volume in the cortex and caudoputamen. DISCUSSION: The present results endorse the neuroprotective effect of our method of hypothermia in permanent focal cerebral ischemia at an endpoint of 1 week under the following two conditions: (1) reduction of muscle and caudoputamen temperature to 29 and 31 degrees C, respectively; (2) maintenance of the mean arterial blood pressure above 90 mmHg during hypothermia.

Astrocytic activation and delayed infarct expansion after permanent focal ischemia in rats. Part I: enhanced astrocytic synthesis of s-100beta in the periinfarct area precedes delayed infarct expansion.

An astrocytic protein S-100beta enhances the expression of inducible nitric oxide synthase in cultured astrocytes at micromolar concentrations, leading to nitric oxide-mediated death of cocultured neurons. The present study examined whether S-100beta production by reactive astrocytes accumulating within the periinfarct area was related to delayed expansion of infarct volume after permanent middle cerebral artery occlusion in the rat. After rapid increases during the initial 24 hours, the increase of infarct volume then decelerated while maintaining the increasing tendency until 168 hours in this model, attaining a significant difference compared with that at 24 hours. In the periinfarct area, the number of reactive astrocytes expressing both S-100 and glial fibrillary acidic protein, the tissue level of S-100beta as measured by the sandwich enzyme-linked immunosolvent assay method using anti-S-100beta monoclonal antibody, and the number of terminal deoxynucleotidyl transferase-mediated 2;-deoxyuridine 5;-triphosphate-biotin nick end labeling-positive cells were significantly increased preceding the delayed expansion of infarct volume. The CSF concentration of S-100beta showed a biphasic increase, presumably reflecting the immediate release from astrocytes within the ischemic core and the subsequent production in reactive astrocytes within the periinfarct area. These results show for the first time that the enhanced synthesis of S-100beta by reactive astrocytes participates in the inflammatory responses within the periinfarct area, which may be related to the occurrence of delayed infarct expansion as a major component of the cytokine network.

Astrocytic activation and delayed infarct expansion after permanent focal ischemia in rats. Part II: suppression of astrocytic activation by a novel agent (R)-(-)-2-propyloctanoic acid (ONO-2506) leads to mitigation of delayed infarct expansion and early improvement of neurologic deficits.

A novel agent, (R)-(-)-2-propyloctanoic acid (ONO-2506), has a unique property in that it modulates functions of activated cultured astrocytes, including pronounced inhibition of S-100beta synthesis. The present study examined whether administration of this agent would mitigate the delayed expansion of infarct volume and the neurologic deficits after permanent middle cerebral artery occlusion (pMCAO) in rats. Daily intravenous administration of ONO-2506 (10 mg/kg) abolished the delayed infarct expansion between 24 and 168 hours after pMCAO, whereas the acute infarct expansion until 24 hours was unaffected. The agent significantly reduced the expression of S-100beta and glial fibrillary acidic protein in the activated astrocytes and the number of terminal deoxynucleotidyl transferase-mediated 2;-deoxyuridine 5;-triphosphate-biotin nick end labeling-positive cells in the periinfarct area. The neurologic deficits were significantly improved, compared with the vehicle-treated groups, as early as 24 hours after the initial administration of ONO-2506. The agent had a wide therapeutic time window of 0 to 48 hours after pMCAO. These results indicate that because of the pharmacologic modulation of astrocytic activation induced by ONO-2506, symptoms can regress whereas delayed expansion of the lesion is arrested. Pharmacologic modulation of astrocytic activation may confer a novel therapeutic strategy against stroke.

Presigmoid transpetrosal approach for the treatment of a large trochlear nerve schwannoma--case report.

A 61-year-old man presented with a rare, large trochlear nerve schwannoma manifesting as left-sided weakness and hypesthesia, bilateral bulbar pareses, and trochlear nerve paresis persisting for 3 months. T1-weighted magnetic resonance imaging with gadolinium revealed an intensely enhanced, well-circumscribed lesion with multicystic formation occupying the prepontine and interpeduncular cisterns and compressing the pons and midbrain with greater extension to the right. The mass was completely removed through the presigmoid transpetrosal approach with preservation of the posterior cerebral, superior cerebellar, and basilar arteries and their branches. Neuroradiological examination after 3 years demonstrated no recurrence. Enlargement of a tumor in the cisternal portion is inclined to involve and/or encase the adjacent major arteries and their branches. The presigmoid transpetrosal approach is one of the best surgical routes to remove a large trochlear nerve schwannoma safely and completely.