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Five cases of traumatic subdural hematomas in the subacute stage (from 7 to 20 days after head injury) were treated in one male and four females, aged from 63 to 82 years, with evacuation via craniotomy in three and aspiration via burr hole surgery in two. All hematomas were evaluated by T1-, T2-, and diffusion-weighted magnetic resonance imaging, and measurement of the apparent diffusion coefficient (ADC). Diffusion-weighted imaging showed the hematoma as a crescent high intensity area with a low intensity rim close to the brain surface (two-layered structure) in four cases and as high intensity with low intensity components in one case. The high intensity areas under the dura mater on diffusion-weighted imaging appeared as homogeneous high intensity on T1- and T2-weighted imaging in four cases, and inhomogeneous high intensity on T1- and isointensity on T2-weighted imaging in one case. The mean ADC value of the high intensity areas was 0.58 +/- 0.23 (mean +/- standard deviation) x 10(-3) mm2/sec. The operative findings revealed the high intensity areas as solid clots. The low intensity areas on diffusion-weighted imaging appeared as homogeneous high intensity in four cases and inhomogeneous isointensity with high intensity components in one case on T1- and T2-weighted imaging. The mean ADC value of the low intensity areas was 2.03 +/- 0.27 x 10(-3) mm2/sec. The operative findings revealed the low intensity areas as mixtures of resolved clot and cerebrospinal fluid. Diffusion-weighted imaging showed the characteristic two-layered structure in traumatic subdural hematomas in the subacute stage, and analysis of the ADC values was useful for differentiating solid from liquid hematoma and for selection of the surgical procedure.

The diffusion-weighted magnetic resonance (MR) imaging characteristics of chronic subdural hematoma and the correlation between hematoma liquidity and apparent diffusion coefficient (ADC) were investigated in 26 consecutive patients, 16 males and 10 females aged 42 to 92 years (mean +/- SD 73.3 +/- 13.1 years), with 31 chronic subdural hematomas. The chronic subdural hematomas were divided into homogeneous, separate, and trabecular types based on diffusion-weighted MR imaging findings. Almost all hematomas were low intensity on diffusion-weighted imaging, and the mean ADC value was 1.81 +/- 0.79 x 10(-3) mm2/sec. The high intensity areas in the subdural hematomas consisted of several types: high intensity line along the dura mater (subdural hyperintense band), high intensity along the intrahematoma septum, and laminar shape along the inner membrane. The subdural hyperintense bands accounted for almost all high intensity areas in the subdural hematomas. The mean ADC value of the high intensity areas was 0.76 +/- 0.24 x 10(-3) mm2/sec, close to that of the normal brain. The subdural hyperintense bands were considered to be intracellular and/or extracellular methemoglobin based on the T1- and T2-weighted imaging and intraoperative findings. The subdural hyperintense band is an important finding indicating relatively fresh bleeding from the outer membrane. Diffusion-weighted imaging shows liquid subdural hematoma as low intensity, and measurement of the ADC values can differentiate between liquid and solid components of the chronic subdural hematoma.

A 59-year-old male presented with a left organized subdural hematoma. The hematoma appeared as a homogeneous low density area on brain computed tomography and as hyperintense and isointense area on both fluid-attenuated inversion recovery and T2-weighted magnetic resonance (MR) imaging. Echo-planar diffusion-weighted MR imaging showed a crescent hyperintense area under the dura mater and an irregular hypointense area over the brain surface in the left subdural space. The apparent diffusion coefficient (ADC) values of the solid and liquid hematoma were 0.86 ± 0.32 × 10-3 and 2.56 ± 0.39 × 10-3 mm2/sec, respectively. The ADC value of the solid hematoma was similar to acute subdural or intraparenchymal hematoma, and that of the liquid was similar to cerebrospinal fluid. Burr-hole surgery failed to remove all the hematoma, and he complained of persistent headache. The hematoma was removed through a craniotomy without further neurological deficits. Organized subdural hematoma often requires craniotomy for evacuation because of its solid content. Diffusion-weighted MR imaging and measurement of ADC values can differentiate solid from liquid hematoma, so are useful for selection of the surgical procedure.

The potential antitumor effect of MX2, a new lipophilic morpholino anthracycline, was compared with those of ACNU or doxorubicin (DOX) using two different rodent glioma models. A mouse subcutaneous glioma model (203 glioma) was used to measure the effect of each drug on reducing the glioma size and a rat 9L intracerebral glioma model (9L glioma) was used to assess the antitumor effect on survival rate in a clinically similar fashion. Treatment with ACNU inhibited tumor growth by 94.6% (p < 0.0001) and complete regression of the tumor was observed in 3 of 25 (12.0%) of the ACNU-treated cases. Tumor growth was inhibited by 32.4% with DOX despite a tendency (p < 0.16) and by 59.4% with MX-2 (p < 0.001); neither of these drugs resulted in complete tumor regression. In the intracerebral glioma rats, only ACNU tended to ameliorate survival rate, but there was no statistical significance. These results suggest that ACNU has the most potent effect but MX2 can be an option for chemotherapy of malignant gliomas. Interestingly, all three drugs significantly elevated the brain water content on both the ipsilateral and contralateral sides of the tumor, although they did not induce brain edema in the normal rat brains. Careful management of brain edema might be required regardless of the drug used during chemotherapy to maximize the prognosis of glioma patients.

A vasoconstrictor peptide, endothelin-1 (ET-1), has been identified as one of the causative substances in cerebral vasospasm after subarachnoid hemorrhage. We investigated whether doxorubicin, an RNA synthesis inhibitor, effectively suppresses induction of ET-1 in the rat vasospasm model. Blood was injected around the right femoral artery and the left one was used as an internal control. Seven days later (day 7), diameters of the right femoral arteries narrowed to about 60% and this vasoconstriction was prevented by clinical dose (0.6 mg/kg) or one third of its dose of doxorubicin injected on day 1. Reverse transcriptase-polymerase chain reaction analysis demonstrated that expression of ET-1 mRNA in the vasospastic artery was not detected in doxorubicin-treated rats. It is concluded that doxorubicin effectively inhibits aberrant expression of ET-1 in the vasospasm-destined artery in the rat.

A 47-year-old male receiving anticoagulant therapy for thrombophlebitis in the left leg for several years presented with mild left hemiparesis and ipsilateral hypesthesia. The cause of the thrombophlebitis was still unknown. Magnetic resonance (MR) imaging showed subacute thrombosis of both the superior sagittal sinus (SSS) and a cortical vein in the right cerebral hemisphere. Fluid attenuation inversion recovery axial MR imaging demonstrated these lesions more obviously than conventional T2-weighted axial MR imaging. Right carotid angiography showed a partial SSS filling defect and occlusion of the cortical vein with collateral circulation. Coagulation studies revealed decreases in both protein C activity and antigen levels with normal levels of blood coagulation factors II, VII, IX, and X and protein S activity and antigen. The patient's mother had normal levels of both protein C activity and antigen, but his father had decreased levels. The diagnosis was SSS and cerebral cortical venous thrombosis caused by congenital protein C deficiency. The patient was treated conservatively, and his clinical course was uneventful. His neurological dysfunctions recovered within approximately 3 weeks after the onset. Ten months later, right carotid angiography showed recanalization of the SSS and partial filling of the cortical vein. Anticoagulant therapy has been continued, and no cerebral venous thrombosis has recurred during the 1.5 years after the onset.

We investigated whether anticoagulant therapy with heparin or a selective thrombin inhibitor, argatroban, may ameliorate the postischemic cerebral circulation and attenuate mortality after 10 min of forebrain ischemia. Postischemic subcutaneous injection of argatroban (5 mg/kg) significantly attenuated mortality (9.1%) compared with non-treatment (45.5%) during 14 days’ observation period. This effect coincided with: (1) increased cortical CBF after reperfusion; (2) attenuation of brain edema; and (3) less severe cell damages in the cerebral cortex. In contrast, nine of the 22 gerbils treated with heparin (830 IU/kg) were found dead on the next day due to massive bleeding in the surgical wound and 13 bleeding-avoided gerbils did not show significant amelioration in mortality (30.8%). These findings suggest that argatroban is an effective anticoagulant for prevention of cell damage after a relatively long forebrain ischemia.

Retrospective analysis in co-operative study of hydrocephalus at institutions of members of the Research Committee on Intractable Hydrocephalus sponsored by the Ministry of Health and Welfare of Japan was performed to determine the functional prognosis. For clinico-epidemiological study we classified non-tumoral hydrocephalus into eight types based on its etiology and the time of onset. Analysis of the 1,450 cases of hydrocephalus stored in the database obtained from the study was performed in order to find intractable factors in terms of factors related to patients and management. Analysis of the cases stored in the database revealed that the following types and conditions were found to be intractable factors: 1. Early fetal hydrocephalus. 2. Overt neonatal hydrocephalus. 3. Hydrocephalus associated with such severe brain malformations as hydranencephaly, holoprosencephaly and lissencephaly. 4. Hydrocephalus associated with severe brain damage. 5. Hydrocephalus associated with epilepsy. 6. Hydrocephalus shunted late after detection. 7. Hydrocephalus complicated by a shunting operation. It is impossible to determine prior to treatment whether or not a shunting operation is indicated for the patient with intractable factors, however, they may be a useful pre-operative indicator of prognosis. For the management of hydrocephalus, secondary intractable hydrocephalus may be preventable if we treat it appropriately before it becomes intractable.

Purpose: To report an important complication related to carotid stenting. Methods and Results: A 71-year-old man with symptomatic subtotal occlusion of the left internal carotid artery had a 30-mm lesion treated percutaneously with implantation of 2 stents. Although the procedure was completed satisfactorily, left intraventricular hemorrhage occurred 4 hours later, possibly related to hyperperfusion injury. The patient expired 30 days after the stent procedure. Preoperative single-photon emission computed tomography revealed severely reduced vasoreactivity in the affected territory after acetazolamide challenge. Conclusions: The risk of hyperperfusion injury must be considered and minimized in patients with significant restriction of regional vasoreactivity. We recommend that cerebral hemodynamic status be determined prior to carotid stenting.

The purpose of this study was to assess the safety and efficacy of percutaneous transluminal cerebral balloon angioplasty (PTCBA) of extra- and intra-cranial arteries by investigating procedural outcome. Eighty haemodynamically significant extra- and intra-cranial lesions (% diameter stenosis > 70) in 74 clinically symptomatic patients were treated by elective and initial PTCBA between March 1991 and February 1996 and thereafter followed. Death, stroke, surgery, or repeated angioplasty of restenosis or new lesions were regarded as cerebral events after the initial PTCBA. The procedural and clinical success rates were 81 % (65 of 80) and 81 % (60 of 74), respectively. Progressively ischaemic symptoms disappeared completely after clinically successful dilatation. Angiographic restenosis rate at 3 months was 22 %(14 of 65). By life-table method, the death/stroke risk was 16 %, and any cerebral event risk was 49 % at 2 years following PTCBA, respectively. The most common of first cerebral events presented was repeated angioplasty of restenosis. In conclusion, PTCBA has great efficacy in decreasing recurrent neurological symptoms and produces a favourable short-term outcome, whereas restenosis limits long-term benefit.

Pineal parenchymal cell tumors (PPCTs) with or without metastasis into the lumbar region by way of the cerebrospinal fluid were treated successfully with combination chemotherapy using cisplatin, vinblastin, and bleomycin (PVB) or cisplatin and vinblastin (PV) and low-dose irradiation (25 approximately 30 Gy). Our series included a case of pineoblastoma, two cases of mixed pinocytoma/pineoblastoma, and a case of pineocytoma, compared to which the data held by the All Japan Brain Tumor Registry (AJBTR) included information on 47 cases pineocytoma and 20 of pineoblastoma. All our patients have survived, with scores of 90% or over on Karnofsky's performance scale, for 2-12 years of follow-up so far; however, the 5-year survival rates of the patients recorded by AJBTR were 83% for pineocytoma treated with radiation and 43% without radiation; and 42% for pineoblastoma treated with radiation and 50% without radiation. Incomplete or varied chemotherapeutic regimens used in different medical centers to treat PPCTs precluded an evaluation such as was made by AJBTR. Our results suggested that combination chemotherapy with low-dose back-up radiotherapy may be the treatment of choice for primary or recurrent disease with or without dissemination in PPCTs.

Congenital hydrocephalus was induced by intraperitoneal administration of antipregnant rat kidney serum (APRKS) into rats at 9 days of pregnancy. To clarify a correlation between the oncogenes and expression of hydrocephalus, immunostaining of the fetal rat nervous system for p53 was carried out using Ab-1, a pantropic antirat p53 antibody, and Ab-3, raised against a mutant form of rat p53, Ab-1 staining was observed in cells of the neural plate of the fetus, the yolk sac, and the placenta. Because no staining occurred with Ab-3, it was likely that the p53 induced by antiserum injection was the wild-type protein. This result indicated that p53 may represent a reparative reaction to DNA damage from the APRKS; also, when DNA is irreparably damaged, p53 could induce apoptosis by favoring transcription of a gene encoding an inducet of apoptosis. Insufficient apoptosis, on the other hand, may induce failure of fetal development, contributing in particular to congenital hydrocephalus and other central nervous system anomalies.

We report a case of Rathke's cleft cyst associated with cholesterin granuloma in an 8-year-old girl with apoplexy. She was admitted to our hospital in April 1996 because of repeated headache and deep ophthalmic pain, without any visual disturbance. Computed tomography (CT) of the pituitary demonstrated an intrasellar isodense mass extending to the suprasellar cistern. Magnetic resonance imaging (MRI) showed a high-intensity mass on both T1- and T2-weighted images. The preoperative diagnosis of this lesion was Rathke's cleft cyst associated with a craniopharyngioma and/or hemorrhage. Transsphenoidal microsurgery was performed, and a bloody coffee-like serous and mucinous-yellowish substance was evacuated. Curettage of the wall removed the yellowish hard mass and soft membranous tissue. Histological examination of this tumor revealed a Rathke's cleft cyst with cholesterin granuloma.

To investigate the pathogenesis of congenital hydrocephalus the brains of HTX rats aged between 16 days and 4 weeks and the brains of normal Wistar rats of the same ages were examined. In the fetal HTX rat brains, the lateral ventricles were symmetrically dilated from 20 days of gestation. The neuroepithelium bordering the ventricles showed thinning with cellular disarrangement and deformity. Similar neuroepithelial abnormalities were also found in the lateral ventricles of the HTX rat brain with no macroscopic signs of hydrocephalus at 20 days of gestation. The neuroepithelium showed flattening of the cells, widening of the intercellular spaces, formation of microvilli on the detached lateral cell surfaces, and frequent macrophage infiltration. On the other hand, the neuroepithelial cells of the third ventricle and the aqueduct were affected less severely or showed no significant abnormalities. Immunohistochemically, most of the neuroepithelium and ependyma of the lateral ventricles were positive for vimentin in both prenatal and postnatal hydrocephalic HTX rats, while a small number or none of those in normal control rats were positive. These morphological changes suggested that preferential involvement of the lateral ventricular neuroepithelium might be closely associated with the pathogenesis of congenital hydrocephalus in HTX rats.

遅発性神経細胞死にアポトーシス(programmed cell death)が関与しているという最近の報告は,「海馬CA1の神経細胞が短時間の前脳虚血に脆弱で選択的な細胞死を引き起こすことは,将来の長時間の虚血侵襲の際に脳全体と生命を守っていることに役立っている」という仮説が成り立つ可能性を示唆する.我々は,この仮説を検証する一つの実験方法として,砂ネズミを用い,予め5分間の前脳虚血を負荷せずに15分間前脳虚血を加えた群(A群)と,予め5分間の前脳虚血を負荷し海馬CA1の選択的な細胞死を生じさせておき,10日後に15分間前脳虚血を負荷した群(B群)において,2週間の観察で,B群では有意に生存率が高く,体重減少も軽減していることを前回報告した(脳卒中19: 145-152, 1997).しかし,2週間生き残った砂ネズミの組織学的検討では両群の違いはほとんどなかったため,今回は死亡する前の時点での脳浮腫測定および組織学的解析を新たに行った.大脳の水分含有量を15分間前脳虚血の2時間後,2日後,7日後について調べたところ,B群はA群より脳浮腫の増加が有意に抑制されていた(p

The outcome of treatment for malignant brain tumors is still disappointing. For this reason, total removal of the tumor is required to obtain a better outcome. It is acknowledged that en bloc total removal of a tumor by lobectomy results in a better outcome than subtotal or partial removal. For extensive removal of a tumor, recognition of the location, infiltration, and cleavage of the tumor is very important. We tried to carry out intraoperative ultrasonography in order to obtain data about brain tumors. We examined three cases of glioblastoma in the frontal region, two in the temporal region, and one in the occipital region, and a case of recurrent malignant meningioma in the temporal region.Extra- and intradural intraoperative ultrasonography was carried out, and silastic or plastic tubes were implanted around the tumor under ultrasonographic guidance. Thus en bloc total removal of the tumor was carried out successfuly without any neurological deficit. The application of intraoperative ultrasonography for malignant brain tumors is very useful, and should help to improve postoperative outcome.

Delayed effect of radiation injury to the central nervous system often results in improper prognosis for the patients with malignant brain tumors. Two types of cell, the endothelial cell and the oligodendrocyte, are considered to be causative lesions for delayed radiation injury. Recently, morphological studies with both light and electron microscope have also indicated involvement of apoptosis at the acute stage of radiation injury. In the rat radiation injury model, we first examined the capillary endothelial cells when they were damaged after irradiation, using immunohistochemical analysis of endothelial blood antigen (EBA) as one of the indicators of normal function of the blood-brain barrier (BBB). Secondly, we examined the types and location of DNA-fragmented cells using in situ end-labeling using the TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling) method. A single dose of 10, 20 or 30 Gy was irradiated to the hemispheres and the brains were analyzed at 3, 6 and 12 months later. Although damage of endothelial cells was seen in the brains at 6 months after 20 Gy irradiation, disruption of BBB, as indicated by no immunoreactivity of EBA, occurred only in the brains at 12 months after 30 Gy irradiation. DNA fragmentation, indicated by TUNEL positive cells, were shown in the oligodendrocyte, astrocytes and endothelial cells in the brains at 6 months after 20 Gy irradiation. The results suggest that both disruption of BBB and apoptosis in the glial cells and endothelial cells are involved in the delayed radiation injury in the rat brain.

The career of one neurosurgeon interested in pediatric neurosurgery is described, with reference to the people who influenced him and his own publications.

Cytotoxic T lymphocytes (CTL) against autologous malignant brain tumor were generated in peripheral blood lymphoid cells (PBL) prepared from a patient with a malignant brain tumor by stimulation of the cultured PBL for 7 days with attenuated Crossreactive malignant melanoma (MM2) cells pretreated with mitomycin C. The Crossreactive MM2 cells were effective for antigen stimulation for CTL induction in place of autologous glioblastoma cells, which are difficult to expand in culture. The optimal ratio between nylon wool‐passed T lymphocytes and nylon wool‐adherent accessory cells to induce CTL in the patient's PBL was found to be 25 to 1. In vitro ‐activated CTLs induced by MM2 were cytotoxic not only to MM2, but also to the autologous tumor cells in an HLA class I‐restricted manner, and their surface phenotype was found to be CD3+ and CD8+. CTL therapy using cross‐reactive allogeneic tumor cells as the stimulator could be clinically valuable to treat malignant brain tumors.

Thalamic neurons were identified by activity related to passive joint movement, active joint movement, tapping stimulation, and light touch stimulation during surgery to treat movement disorders. The neurons were classified into three types: movement-related neurons, tapping-related neurons, or superficial sensory neurons. Tapping-related neurons had characteristics of lemniscal sensory neurons and occupied the border area of movement-related neurons and superficial sensory neurons. Tapping-related neurons showed a laminar distribution 1.0-1.5 mm in width in the anterodorsal region of the nucleus ventrocaudalis. Results suggest that the distribution pattern of tapping-related neurons in the human thalamus is consistent with the functional distribution pattern found in the monkey thalamus.

The long-term survival probability, causes of delayed mortality, and relationship between short-term outcome and long-term survival after aneurysmal subarachnoid hemorrhage were retrospectively studied in 106 patients followed up for longer than 5 years. The Kaplan-Meier cumulative survival probabilities at 1 month, 6 months, and 5 years were 85.9%, 79.2%, and 66.8%, respectively. Six months after the onset, 41 patients made a good recovery (GR) and 34 were moderately disabled (MD). On the last follow-up day, 64 had good outcome (GR or MD) and eight had died. In contrast, there were nine patients with poor 6-month outcome (severe disability or vegetative state), seven of whom died within 5 years. Five of these seven patients had experienced intraventricular hemorrhage (IVH) on admission. A total of 15 patients died beyond 6 months, five died of complications related to shunts. Six-month outcome is a predictor of long-term survival and delayed mortality. Improved long-term survival requires the development of better management for IVH, improved 6-month outcome, and careful follow-up of patients who undergo shunting.

遅発性神経細胞死にアポトーシス (programmed cell death) が関与しているという最近の報告は, 「海馬CA1の神経細胞が短時間の前脳虚血に極めて脆弱で選択的な細胞死を引き起こすことは, あたかも電気回路のフユーズの様な機序で, 将来の長時間の虚血侵襲の際に脳全体と生命を守っている」という仮説の可能性も示唆する.我々は, この仮説を検証する一つの実験方法として, 砂ネズミを用い, 5分間の前脳虚血を前もって負荷し海馬CA1の選択的な細胞死を生じさせておき, 10日後に15分間の前脳虚血を負荷した場合, 広範な脳の神経細胞死が予防でき, 生体の死も防ぐことが出来るか検討した.予め5分間虚血を負荷せずに15分間虚血を加えた群 (A群) の2週間の生存率は41%であったが, 予め5分間虚血を負荷し10日後に15分間虚血を加えた群 (B群) は65%と統計学的な有意差をもって生存率が向上し, また体重減少もより軽度であった.しかし, 組織学的検討では, 海馬CA3, 海馬支脚での細胞死は両群で差がなく, また, 特に大脳皮質の表層での神経細胞死はB群がA群に比しより重篤であった.予め負荷しておいた5分間前脳虚血は, 生体にとって好ましい効果を示したが, その機序に関しては今後の検討が必要である.

Since hydrocephalus is a multifactorial disease with a diverse pathogenesis, no single, truly ideal classification of its exists. Hydrocephalus has been classified from various standpoints, each classification reflecting the current level of knowledge about hydrocephalus. Hydrocephalus needs to be classified according to the purpose of the study. There are two major categories of classification of hydrocephalus: academic and practical. Untreatable hydrocephalus still occurs. We propose a practical clinical classification based on the time of onset and the etiology for use in the clinico-epidemiologic study of intractable hydrocephalus and its future management.

We investigated the brainstem auditory evoked potentials (BAEPs), somatosensory evoked potentials (SEPs), and electrically elicited blink reflexes (BRs) to evaluate the brainstem function in 31 patients with meyelomeningocele (MMC) including 22 with Chiari type-II malformation. The I-III interpeak latency (IPL) of the BAEPs and the N9-N13 IPL of the SEPs tended to become gradually prolonged from the normal range with increasing age. The III-V IPL of the BAEPs and the N13-N20 IPL of the SEPs were initially prolonged and decreased progressively to the normal range. These findings indicated a gradual latency shortening of the brainstem components and latency prolongation of the peripheral components. Thus, while primary brainstem dysfunction may improve with age, secondary dysfunction due to stretching and elongation of the lower cranial nerves and cervical nerve roots may intensify. The BRs showed an abnormal R2 in 90% of the cases, disclosing subclinical lesions in the medulla oblongata which were not detected by BAEPs alone. BAEPs, SEPs and BRs were combined to yield a functional evaluation of the brainstem and lower cranial nerves that could not be done by magnetic resonance imaging alone. No close relation was found between electrophysiological abnormalities and the degree of hindbrain anomaly by neuroimaging.

A female neonate with myelomeningocele but without Chiari type II malformation suffered from apneic spells. Magnetic resonance imaging showed no obvious brainstem anomaly. Brainstem auditory evoked potentials were initially abnormal and subsequently deteriorated during the 6 months after birth. The brainstem deficits were not reversed by a ventriculoperitoneal shunt. She died of respiratory distress and cardiac failure at 2 years of age. This case indicates an intrinsic dysfunction in the brainstem of patients with myelomeningocele not complicated by Chiari type II malformation.

Venous malformations in the posterior fossa are relatively rare. Although the introduction of CT and MRI has made them easier to detect, their treatment is still controversial. Based on our experience with six patients and a review of the literature, we have tried to establish guidelines for their treatment. Since they have a benign natural course and may provide venous drainage in the posterior fossa, venous malformation found incidentally, unruptured venous malformation with nonhaemorrhagic complications, and those accompanied by small intracerebellar haematoma of less than 2 cm in diameter due to their rupture, should be treated conservatively unless they are associated with a coexistent malformation. Venous malformation with intracerebellar haematoma larger than 3 cm or reexpansion of the haematoma due to rebleeding should be treated surgically by evacuation of the haematoma. Resection of venous malformations in the posterior fossa should be restricted to cases in which the malformation is small and does not serve as a functional venous drainage route. Radiation therapy, including the "gamma-knife", may be a treatment of choice in the future.

The effects of active oxygen species in the development of congenital hydrocephalus have been investigated. Superoxide dismutase (SOD) is one of the scavengers of active oxygen species and there have been many recent reports on the relationship between neurological disorders by active oxygen species following reperfusion for ischemic brain and SOD. In this study, the localization of Cu-SOD and Zn-SOD in WIC-Hyd congenitally hydrocephalic rat brains was identified by the enzyme unlabeled antibody method. We examined the localization of SOD in the choroid plexus, hippocampus, and ependymal cells of the lateral ventricle and aqueduct of WIC-Hyd rats. SOD was hardly observed in the choroid plexus and faintly localized in the hippocampus and ependymal cells of the congenitally hydrocephalic brain, but was observed equally in the cytoplasm of the choroid plexus, hippocampus, and ependymal cells in control animals. In the hippocampus, less SOD was found in hydrocephalic rats than in controls. The SOD was slightly observed in the CA1 pyramidal cells in hydrocephalic rats. In the lateral ventricle and aqueductal ependyma, less SOD was found in hydrocephalic than in controls rats. The amount of Cu, Zn-SOD in the congenitally hydrocephalic rat brain was less than in the control, especially in the choroid plexus. Therefore, we suspect that the production of SOD is congenitally reduced in the congenitally hydrocephalic rat brain, and this may promote the impairment of the function of choroid plexus and cilia due to increased active oxygen species. The reduction of SOD in the choroid plexus, hippocampus and ependymal cells of ventricles or aqueduct may promote the development of hydrocephalus in the congenitally hydrocephalic rat.

頚部動脈閉塞性病変を有する患者の治療を安全に行うためには, 虚血性心疾患の有無とその程度とを正しく評価することが必要だと思われる.そのため1990年9月1日から1991年3月31日までの間に, 脳梗塞で当科に入院し, 頚部にBruitを聴取した5例の患者に, 頭頚部血管造影と冠動脈造影とを施行した.5例とも50%以上の頚部動脈閉塞性病変を有した.全例喫煙歴があり, 3例が糖尿病合併例であった.全例心室壁運動は正常範囲であったが, 冠動脈3枝疾患が1例, 2枝疾患が1例, 1枝疾患が2例であった.病変を有しなかったのは1例のみであった.頚部動脈病変を有する患者は冠動脈病変を有する可能性が高い.重症の冠動脈病変を有する患者に対して, 外科的治療を施行することは危険を伴う.どういう症例に術前の冠動脈造影が必要なのか, どちらの治療を優先するべきか, 頚部動脈閉塞性病変の治療に携わる医師は, 今後よく検討する必要があるのではないかと考える.

Ossifying fibroma is relatively common in the maxilla, but rare in the cranial vault. A 10-year-old girl was referred for painful swelling of the left temporal region. On admission, she presented no abnormal physical and neurological findings except for the painful swelling. Plain skull X-ray films showed a radiolucent lesion of the left temporal bone about 4 cm in diameter, with a hyperostotic area of the parietal side. Computed tomography scan using bone window level also showed an abnormal density lesion in the same site. Curettage of this tumor was performed from a cosmetic point of view and at the family's petition. Histological examination showed vascular fibrous tissue in which lamellar bone was surrounded by osteoblasts.

BACKGROUND AND PURPOSE Our objective was to find the specific angiographic characteristics of atherosclerotic lesions that indicate suitability for intracranial percutaneous transluminal cerebral balloon angioplasty (PTCBA). METHODS Forty-two clinically symptomatic patients with 42 hemodynamically significant intracranial lesions (>70% stenosis) were treated by PTCBA between January 1992 and May 1996. Before treatment, the patients were assigned to three groups according to the angiographic characteristics of the lesions, as follows: type A, short (5 mm or less in length) concentric or moderately eccentric lesions less than totally occlusive; type B, tubular (5 to 10 mm in length), extremely eccentric or totally occluded lesions, less than 3 months old; and type C, diffuse (more than 10 mm in length), extremely angulated (>90 degrees) lesions with excessive tortuosity of the proximal segment, or totally occluded lesions, and 3 months old or older. The patients were followed up for a period of 1 month to 6 years to compare the results of PTCBA treatment among the three groups. Primary end points were death, stroke, or bypass surgery. RESULTS The clinical success rates for the type A, B, and C groups were 92%, 86%, and 33%, respectively. Cumulative risks of fatal or nonfatal ischemic stroke or ipsilateral bypass surgery in type A, B, and C groups were 8%, 26%, and 87%, respectively. The cumulative risk of 8% among patients in the type A group appeared to be smaller than in studies reported in the literature. CONCLUSION PTCBA for intracranial simple (type A) lesions yields a favorable clinical outcome for symptomatic patients.

Schwannomas of the hypoglossal nerve are interesting because of the variety of associated symptoms. We describe here a Schwannoma of the hypoglossal nerve with extra and intracranial extensions which compressed the brain stem.A 62-year old female was admitted to our hospital because of a tumor on the right side of the neck and occasional headaches. Cranial nerves I to XI were intact, but paralysis and atrophy of the right side of the tongue were noted. She had signs of increased intracranial pressure. Computed tomographic scans were quite useful to delineate the destruction of the hypoglossal canal and jugular foramen. Magnetic resonance imaging scans were also informative, showing the relationship between the tumor and the surroundings. Staged otological and neurosurgical resections were required because of the size of the intracranial extension. The infratemporal fossa approach was used to resect the extracranial tumor.

A 65-year-old man, who suffered from recurrent syncopal attacks after a minor stroke, was treated by percutaneous transluminal angioplasty using the kissing balloon technique (KBT) in which two angioplasty balloons were inflated simultaneously for the right carotid bifurcation stenoses. Because they involved the right internal carotid artery and the right external carotid artery coupled with the right proatlantal intersegmental artery, neither of them should close after the angioplasty. Bifurcation stenoses were sufficiently dilated with KBT and no syncopal attacks have recurred since the treatment.

We report our initial experience of carotid and vertebral stenting. Three haemodynamically significant extra-cranial lesions (% diameter stenosis >70) in 3 clinically symptomatic patients were treated by stenting between March 1996 and September 1996. Two lesions of the internal carotid arteries were ostial and in one case a subtotal stenosis and ostial lesion of the vertebral artery were observed. All lesions looked more widely and smoothly dilated by stenting than by ordinary standard balloon angioplasty.

Five cases of traumatic subdural hematomas in the subacute stage (from 7 to 20 days after head injury) were treated in one male and four females, aged from 63 to 82 years, with evacuation via craniotomy in three and aspiration via burr hole surgery in two. All hematomas were evaluated by T1-, T2-, and diffusion-weighted magnetic resonance imaging, and measurement of the apparent diffusion coefficient (ADC). Diffusion-weighted imaging showed the hematoma as a crescent high intensity area with a low intensity rim close to the brain surface (two-layered structure) in four cases and as high intensity with low intensity components in one case. The high intensity areas under the dura mater on diffusion-weighted imaging appeared as homogeneous high intensity on T1- and T2-weighted imaging in four cases, and inhomogeneous high intensity on T1- and isointensity on T2-weighted imaging in one case. The mean ADC value of the high intensity areas was 0.58 +/- 0.23 (mean +/- standard deviation) x 10(-3) mm2/sec. The operative findings revealed the high intensity areas as solid clots. The low intensity areas on diffusion-weighted imaging appeared as homogeneous high intensity in four cases and inhomogeneous isointensity with high intensity components in one case on T1- and T2-weighted imaging. The mean ADC value of the low intensity areas was 2.03 +/- 0.27 x 10(-3) mm2/sec. The operative findings revealed the low intensity areas as mixtures of resolved clot and cerebrospinal fluid. Diffusion-weighted imaging showed the characteristic two-layered structure in traumatic subdural hematomas in the subacute stage, and analysis of the ADC values was useful for differentiating solid from liquid hematoma and for selection of the surgical procedure.

A 59-year-old male presented with a left organized subdural hematoma. The hematoma appeared as a homogeneous low density area on brain computed tomography and as hyperintense and isointense area on both fluid-attenuated inversion recovery and T2-weighted magnetic resonance (MR) imaging. Echo-planar diffusion-weighted MR imaging showed a crescent hyperintense area under the dura mater and an irregular hypointense area over the brain surface in the left subdural space. The apparent diffusion coefficient (ADC) values of the solid and liquid hematoma were 0.86 +/- 0.32 x 10(-3) and 2.56 +/- 0.39 x 10(-3) mm2/sec, respectively. The ADC value of the solid hematoma was similar to acute subdural or intraparenchymal hematoma, and that of the liquid was similar to cerebrospinal fluid. Burr-hole surgery failed to remove all the hematoma, and he complained of persistent headache. The hematoma was removed through a craniotomy without further neurological deficits. Organized subdural hematoma often requires craniotomy for evacuation because of its solid content. Diffusion-weighted MR imaging and measurement of ADC values can differentiate solid from liquid hematoma, so are useful for selection of the surgical procedure.

A 59-year-old diabetic male presented with transient motor aphasia and monoparesis of the right upper limb. Brain CT scan showed a low density area in the left subdural space with a mild midline shift. Magnetic resonance (MR) T2-weighted and fluid-attenuated inversion recovery (FLAIR) imagings revealed homogenous hyperintensity with a hypointense web-like structure in the subdural hematoma. Cervical MR angiography showed no abnormal lesion at the bifurcation of the bilateral common carotid arteries. Conventional cerebral angiography showed an avascular, crescent, space-occupying mass over the left hemisphere without an etiologic lesion of cerebral ischemia. CT perfusion imagings indicated reduced cerebral blood flow (CBF) and prolonged mean transit time (MTT) in the left middle cerebral artery territory underneath the subdural hematoma. No epileptic discharge was found in electroencephalogram. Operative findings indicated that the hematoma was encapsulated with thickened outer and inner membranes including paste-like materials, and the brain surface was intact. Postoperative CT perfusion imagings revealed normal CBF and MTT. The pathophysiological mechanism which the chronic subdural hematoma produces the transient neurological deficit is still uncertain. The mechanical pressure of the hematoma on the neighboring cerebral vessels may cause impairment of blood flow leading to cerebral ischemia and paralysis of function. Our case indicated the transient neurological deficits attributed to a decreased CBF around the subdural hematoma and a change in pressure exerted by the hematoma during changes of head position and increased blood viscosity.

Gamma knife radiosurgery was carried out for spontaneous CCF (carotid-cavernous sinus fistula) in 8 patients (1 male and 7 females), and its results were reported. The ages ranged from 48 to 74 years with a mean of 60.6 years. As initial treatment before radiosurgery, embolization was carried out except in one patient, and radiotherapy was used in two patients. Six patients were in the category of Barrow's type D, and two patients were in the category of Barrow's type B. As it contained the fistula, the lateral wall of the cavernous sinus was irradiated with 8-14.5 Gy (mean 10.8 Gy). As a result, complete obliteration of CCF was confirmed by DSA in seven of the eight patients between 6 and 18 months after radiosurgery. There were no side effects observed during a follow-up period of 8 to 116 months. Although the main treatment for spontaneous CCF is intravascular surgery at present, gamma knife radiosurgery is a useful adjuvant treatment for the residual CCF after embolization.

Object. A cooperative study was undertaken to identify factors that could be used to predict a favorable outcome after extracranial cerebrospinal fluid (CSF) diversion (shunting) in patients with suspected idiopathic normal-pressure hydrocephalus (NPH). Methods. Questionnaires concerning patients with suspected idiopathic NPH were sent to 14 members of the Committee for Scientific Research on Intractable Hydrocephalus, sponsored by the Ministry of Health and Welfare of Japan. After the questionnaires were returned, a retrospective analysis of the responses was undertaken. To be included in the study, patients had to be 65 years of age or older and had to have undergone surgery between October 1995 and October 1998. Clinical measures included degrees of gait disturbance, dementia, and urinary incontinence as evaluated before, 3 months after, and 3 years after shunt placement. Diagnostic tests in various combinations included lumbar puncture in which CSF was withdrawn; intracranial pressure monitoring; measurements of CSF outflow resistance, level of serum α-1-antichymotrypsin, cerebral arteriovenous differences of oxygen content, and cerebral blood flow; and computerized tomography cisternography. In this study, 120 patients were identified as having idiopathic NPH and these patients underwent placement of shunts. A ventriculoperitoneal shunt with a programmable valve was used in two thirds of the patients. At the end of 3 months (early assessment), there was an 80% overall rate of clinical improvement, which dropped to 73.3% of the 105 patients who could be evaluated at the end of the 3-year study. Of the three variables, gait disturbance was most improved, both at early and late testing periods. Shunt complications occurred in 22 (18.3%) of the patients. Conclusions. Patients suspected of having idiopathic NPH did not form a homogeneous group, making it difficult to select those who would most likely respond to CSF diversion. Of the diagnostic studies, the most reliable result was improvement in clinical symptoms following a lumbar puncture in which CSF was withdrawn. The use of a programmable valve is recommended because it offers advantages in preventing problems of over- and underdrainage.

In the natural history of infantile extracerebral fluid collections, subarachnoid fluid collection itself is regarded as a benign lesion, and surgical treatment is not indicated. As this condition is age-related and self-limiting, spontaneous resolution can be expected in most cases by 2-3 years of age. However, out of 20 cases of infantile subarachnoid fluid collection in an 8-year period, 3 infants developed subdural hematoma. Infantile subarachnoid fluid collection seems to be prone to complicate subdural hematoma. Surgical treatment should be considered when subarachnoid fluid collection is complicated by subdural hematoma due to arachnoid ruptures or tearing of the bridging veins. Therefore, all patients should be observed closely and measures should be taken to prevent head trauma since it may precipitate subdural hematoma.

A 67-year-old female with a history of hypertension and cerebral infarction presented with subarachnoid hemorrhage (SAH) (Hunt and Kosnik grade 4). Brain computed tomography (CT) revealed a clot dominantly on the right (Fisher's classification Group 4). Cerebral angiography showed funnel-shaped widenings at the origins of the bilateral posterior communicating arteries. The maximum diameter of the widening was greater than 3 mm, so this widening was called an enlarged infundibular widening. Angiography showed a small bulge protruding posterolaterally from the wall of the right enlarged infundibular widening, and the right posterior communicating artery arose from the apex of the enlarged infundibular widening. Based on the findings of the brain CT and cerebral angiography, the diagnosis was SAH due to rupture of the right enlarged infundibular widening. Approximately 12 hours after the onset, the clot was evacuated through the right pterional approach. Bleeding from the small bulge of the right enlarged infundibular widening occurred intraoperatively, so a right-angled ring clip was applied parallel to the right internal carotid artery to obliterate the rupture point. Postoperatively, she was discharged without neurological deficit, and follow-up CT showed no other new infarction. We recommend clipping rather than wrapping or coating for similar cases of ruptured enlarged infundibular widening.