Incidence of central nervous system tumors in Gironde, France

The incidence of CNS tumors is subject to geographical and temporal variations which are poorly understood. The incidence of these tumors was studied in Gironde, a department of southwestern France with 1,058,911 inhabitants older than 16 years. We recorded any malignant or benign central nervous system (CNS) tumor diagnosed between May 1999 and April 2001 in adults living in Gironde. Three hundred and twenty-nine CNS tumors were diagnosed during the study period. The incidence of CNS tumors in adults was therefore 15.5 per 100,000. Overall, the incidence according to sex was 14.7 for males and 16.2 per 100,000 for females. The incidence rate increased according to age up to 80 years (3.7 per 100,000 for 20-29 years of age to 33.4 per 100,000 for 70-79 years of age) and reduced thereafter for gliomas. Our estimation of the incidence of CNS tumors ranks high among the earlier reports. Further analytic studies are ongoing.     

Etiology of Seizures in the Elderly

Our study covered a 5-year period, and included all patients within a well-defined area who developed seizures after age 60 years. The dominant cause of seizures was a previous stroke, accounting for 32% of all cases. Tumors accounted for 14%, and the cause of seizures remained unknown in 25%. Seizures were recurrent in greater than 80% of patients with first seizure greater than 6 months after stroke. Fifteen of 21 patients with tumors had metastatic tumors. Of the six patients with primary brain tumors, five had malignant gliomas and one had a meningioma. We conclude that epilepsy with onset after age 60 years is more often symptomatic than is epilepsy in younger patients; since seizures were the first sign of a central nervous system (CNS) disease in half of the patients with brain tumors, careful investigation is necessary to reach a correct diagnosis.     

Epidemiology of primary central nervous system tumors in Estonia

During the period from 1986 to 1996, 1,665 cases of primary central nervous system (CNS) tumors were identified in the resident population of Estonia. Histological verification was available in 81% of the cases. Gliomas were more common in men, while meningiomas and neurinomas were more common in women. No significant difference was observed between the sexes for all primary CNS tumors. The age-specific incidence increased from the age of 30, reached a maximum in the age range of 50-69 years and declined in the elderly which may reflect under-diagnosis. The age-adjusted incidence rate for CNS tumors was 8.5/100,000 population. A comparison of our results with those of a previous study carried out in Estonia revealed a significant histology-specific increase in incidence in all age groups.     

Central nervous system (CNS) tumor trends in children in a western Canadian province: a population-based 22-year retrospective study

In Canada, CNS tumors accounted for nearly 22% of the new childhood cancer diagnoses during 1995-2000 in the ≤ 15 year age group. The study's objective was to describe children and youth (age <20 years) diagnosed with CNS tumors in Alberta, Canada during a 22-year period using population-based data. The Alberta Cancer registry was used to extract information, including sex, age and geography, on all CNS (ICCC-3 III) tumor diagnoses during April 1, 1982, and March 31, 2004. Analyses included population summaries and rates. During 22 fiscal years, 568 Alberta children were diagnosed with CNS tumors and nearly 82% of the cases were malignant (461). The majority of cases were male (322, 57%) and the median age at diagnosis was 8 years. The crude rate per 100,000 children increased over the study period from 2.1 in 1983/1984 to 4.2 in 2003/2004. Astrocytoma was the most common diagnosis (257, 45%), followed by medulloblastoma (12%), mixed and unspecified glioma (9%) and ependymoma (9%). There were 86 diagnoses of juvenile pilocytic astrocytoma (55% male) and the crude rates per 100,000 increased during the study (<0.5 in the early years to 1.15 in 2003/2004). Our data suggests an emerging trend with the latter few years having a seemingly higher standardized incidence rate than earlier years. Further study is required to determine if the trend persists.     

Neuropathology and general autopsy findings in AIDS during the last 15 years

A retrospective study of 450 consecutive AIDS autopsy cases (397 males, 53 females; mean age at death 38.4 years) in Vienna, Austria, between 1984 and 1999 compares the central nervous system (CNS) findings in three cohorts: 1984–1992 (190 cases), 1993–1995 (162 cases) and 1996–1999 (98 cases, after introduction of triple antiretroviral therapy) and the relationship of CNS findings to systemic AIDS pathology in the latter two cohorts. In these two groups, following involvement of the lung (85% and 75%, respectively), the brain continued to be the second most frequently involved organ (decrease from 80% to 60%, respectively). Extracerebral protozoal (Pneumocystis carinii, toxoplasmosis), Mycobacterium avium complex, viral [e.g., cytomegalovirus (CMV)], multiple opportunistic organ and CNS infections, and Kaposi sarcoma significantly decreased over time. There was less decrease in fungal infections, while bacterial organ and CNS infections (except for mycobacteriosis), lymphomas, HIV-associated CNS lesions (around 30%), non HIV-associated changes (vascular, metabolic, etc.) and negative CNS findings (10–11%) remained unchanged. Nonspecific CNS changes (e.g., meningeal fibrosis) increased. Extracerebral pathology in subjects with advanced HIV-related CNS lesions showed more frequent but decreasing systemic bacterial and CMV infections than those with negative or nonspecific neuropathology, while other opportunistic and multiple organ infections and lymphomas showed no differences between both groups. In a cohort of drug abusers, HIV encephalitis, progressive multifocal leukoencephalopathy, bacterial infections, hepatic encephalopathy, and negative CNS findings were more frequent than in non-users who showed increased incidence of CMV, toxoplasmosis, or other opportunistic CNS infections, and nonspecific CNS findings; the frequency of lymphomas was similar in both drug abusers and non-users. Similar to a recent autopsy study from San Diego, these data suggest that despite the beneficial effects of modern antiretroviral combination therapy, involvement of the brain in AIDS subjects continues to be a frequent autopsy finding, while the increased incidence of HIV encephalitis in our small cohort of drug users was less than observed in other recent autopsy studies. Received: 7 March 2000 / Revised, accepted: 24 March 2000     

中枢神经系统血管母细胞瘤的年龄分层分析

目的 探讨不同年龄段的中枢神经系统（CNS）血管母细胞瘤（HB）的临床特征、预后及其影响因素。方法 回顾性分析2016年1月至2022年1月手术治疗的86例CNS-HB的临床资料。根据初次手术年龄分为四个年龄段（≤20岁、21~40岁、41~60岁和≥61岁），分析不同年龄段临床特征、预后差异。结果 CNS-HB以颅内压增高症状为主，其次是小脑症状。肿瘤主要位于幕下，其中小脑占65.6%、脑干占17.7%，其次是脊髓（11.5%），幕上极少（5.2%）；实性肿瘤43例（44.8%），囊性肿瘤53例（55.2%）。年龄≤20岁组病程[（1.68±1.87）个月]较年龄≥61岁组[（26.50±50.66）个月]明显缩短（P<0.05）。年龄≤40岁病人VHL病发生率较年龄>40岁病人明显增高（P<0.05）。不同年龄段病人的肿瘤部位、肿瘤性质均无明显差异（P>0.05）。术后41例（42.7%）出现坠积性肺炎，年龄越大，发生肺炎的几率越高（P<0.001）。术后15例（15.6%）出现颅内并发症，实性肿瘤及脑干肿瘤病人术后颅内并发症发生率明显高于囊性肿瘤或肿瘤位于其他部位病人（P<0.05）。末次随访，预后良好78例（81.3%），预后不良8例（18.7%）。多因素logistic回归分析显示男性、肿瘤位于脑干以及实性肿瘤是CNS-HB预后不良的独立危险因素（P<0.001）。结论 年轻HB病人的病程较短，而老年HB病人术后并发症发生率较高，但是年龄不是HB病人预后不良的危险因素，肿瘤部位及肿瘤性质与HB病人不良预后有关。40岁以下病人VHL病发病率较高，建议年轻病人积极进行VHL病的筛查。     

Descriptive epidemiology of malignant brain tumors in the Swiss Canton of Vaud

Incidence registration and survival data from brain neoplasms have been analyzed from the population-based system of the Cancer Registry of the Swiss Canton of Vaud, which has been operating in a particularly favorable environment for surveillance and using an integrated and homogeneous system of cancer registration. Between 1974 and 1987, a total of 401 cases was registered, corresponding to an age-adjusted rate for all malignant histotypes of 5.3/100,000 (world standard) for the period 1975-1980 and 5.0 for 1981-1987 in males, and of 3.9 and 3.7, respectively, in females. Thus, no increase in brain neoplasm incidence has taken place in this population, and indeed some decline has been observed in males, particularly for gliomas (from 2.7 to 2.0). During the most recent calendar period, incidence rates were 2.0 in males and 1.5 in females for gliomas, 0.9 in both sexes for astrocytomas, 0.4 in males and 0.1 in females for oligodendrogliomas, and 1.7 in males and 1.2 in females for other or unspecified histotypes. For both gliomas, astrocytomas and total brain neoplasms, the peak rate was observed in the age group 55-74, and some flattening of rates was registered above age 75. Overall 5-year survival was 16%. While there was no difference between sexes, survival rates were substantially lower at older (greater than or equal to 60 years, 3%) than at younger (less than 60 years, 26%) age, and for gliomas (7% at 5 years) than for other histological types. However, the histotype distribution could not explain the major difference in survival by age, since similar differences were observed for various histotypes.(ABSTRACT TRUNCATED AT 250 WORDS)     

Incidence of epilepsy and predictive factors of epileptic and non-epileptic seizures.

PURPOSE: To estimate the incidence of unprovoked seizures (US) and epilepsy in a general population from the southern part of the Netherlands, in relation to age, sex, etiology and seizure type, and to identify predictive factors of the epileptic and non-epileptic seizures. METHODS: All patients aged > or =14 years with a first seizure or who had undiagnosed seizures before the study period were included. Patients were identified from different sources and were independently evaluated and classified by a team of neurologists. A predictive profile for the occurrence of epileptic and non-epileptic seizures was obtained by stepwise logistic regression analysis. RESULTS: The overall annual incidence was 55/100,000 and 30/100,000 for US and epilepsy, respectively. The age-specific annual incidence of US and epilepsy increased with age and reached 120/100,000 and 62/100,000 for the > or =65 years of age group, respectively. The incidence of epilepsy and US in males was higher than in females and partial seizures prevailed over generalized seizures (40 versus 9/100,000). In up to 35% of the cases with US or epilepsy, the etiology was mainly cerebrovascular disease and brain tumors. Predictors for epileptic versus non-epileptic seizures of organic origin were an epileptiform EEG pattern (OR=0.06) versus a history of hypertension (OR=2.8) or cardiovascular disease (OR=5.4). Strong predictors for seizures of non-organic origin were female sex (OR=2.2) and head injury (OR=2.4). CONCLUSIONS: The incidence of US and epilepsy (overall, and age-, sex-, seizure-specific) was similar to those reported by other developed countries. The predictive factors found in this study may assist in the early diagnosis of seizures.     

Suicide after traumatic brain injury: a population study

OBJECTIVES: To determine the rates of suicide among patients who have had a traumatic brain injury. METHODS: From a Danish population register of admissions to hospital covering the years 1979-93 patients were selected who had had either a concussion (n=126 114), a cranial fracture (n=7560), or a cerebral contusion or traumatic intracranial haemorrhage (n=11 766). All cases of deaths by the end of the study period were identified. RESULTS: In the three diagnostic groups there had been 750 (0.59%), 46 (0.61%), and 99 (0.84%) cases of suicide respectively. Standardised mortality ratios, stratified by sex and age, showed that the incidence of suicide among the three diagnostic groups was increased relative to the general population (3.0, 2.7, and 4.1 respectively). In all diagnosis groups the ratios were higher for females than for males, and lower for patients injured before the age of 21 or after the age of 60. The presence of a codiagnosis relating to substance misuse was associated with increased suicide rates in all diagnosis groups. There was a tendency, among patients with cerebral contusions or traumatic intracranial haemorrhages, for suicide risk to increase with duration of stay in hospital. Cox regression analyses for proportional hazards confirmed that there was a significantly greater risk of suicide among patients with cerebral contusions or traumatic intracranial haemorrhages than among patients with concussion or cranial fractures (hazard ratios=1.42 and 1.50 respectively). There was, however, no evidence of a specific risk period for suicide after injury. CONCLUSION: The increased risk of suicide among patients who had a mild traumatic brain injury may result from concomitant risk factors such as psychiatric conditions and psychosocial disadvantage. The greater risk among the more serious cases implicates additionally the physical, psychological, and social consequences of the injuries as directly contributing to the suicides.     

Brain death in a neurosurgical unit in Japan

Walker states that the incidence of brain death accounts for approximately 1% of all deaths, so that brain death is a common state. According to Jennett et al, the occurrence of brain death is now a relatively frequent event, with about 4000 cases each year in Britain. But the actual circumstances of brain death can not be discovered from any published report. During the last 11 years (1973-1983) at Kyorin University Hospital, we studied 121 cases diagnosed as brain death according to Japanese criteria. The Japanese criteria requires that the pathology be a gross primary brain lesion, so did not concern ourselves with brain deaths due to secondary brain damage. We analysed the factors associated with brain death, that is the annual incidence, age, sex distribution, primary diagnosis and elapsed time from brain death to cardiac death. The increasing incidence of brain death in the last 5 years is probably due to a rise in severely brain-damaged patients (Table 1). In the age distribution, the high number of patients in their fifties presumably reflects the human age tendency for traumatic and vascular disorders respectively (Fig. 1 and Table 2). The fact that males predominate relates to the greater risk faced regarding cerebral trauma (Table 3). The primary diagnoses were cerebrovascular accidents in 60% of the cases especially subarachnoid hemorrhage in 41%, head injury in 31% and brain tumor in 9% (Tables 4 and 5). The elapsed time from brain deaths is measured from diagnosis of clinical brain death to cardiac asystole (Fig. 2). All patients had final cardiac asystole while still being ventilated.(ABSTRACT TRUNCATED AT 250 WORDS)     

Pathological spectrum of neuronal/glioneuronal tumors from a tertiary referral neurological Institute

Neuronal/glioneuronal tumors are uncommon neoplasms of the CNS with frequent association with refractory epilepsy. Reports documenting the entire spectrum of neuronal/glioneuronal tumors are scarce in the literature. Zulch et al. from Germany in a large series reported that neuronal/glioneuronal tumors accounted for 0.4% (38/9000 cases) of all brain tumors, with similar incidence reported from Japan (0.4%), with higher incidence from Korea (2.1%). However, data from the Indian subcontinent are lacking. We reviewed 244 cases of neuronal/glioneuronal tumors of the CNS diagnosed over the last decade at our Institute and they constituted 0.86% of all CNS tumors (244/28061) received in that period. Mean age at presentation was 25.06 years (range: 1–75 years) with male preponderance (M : F = 1.54 : 1). The majority occurred in third decade (76 cases, 31.4%), with only few cases occurring beyond fifth decade (13 cases, 5.3%). Ganglioglioma/gangliocytoma (94 cases, 38.52%) was the most frequent followed by central neurocytoma (86 cases, 35.24%), paraganglioma (32 cases, 13.52%), dysembryoplastic neuroepithelial tumors (DNET) (21 cases, 8.6%), desmoplastic infantile astrocytoma/desmoplastic infantile ganglioglioma (DIA/DIG) (6 cases, 2.45%), papillary glioneuronal tumor (PGNT) (3 cases, 1.22%) and rosette‐forming glioneuronal tumor (RGNT) (1 case, 0.4%). Association with seizures was noted in 40.95% of cases. Glioneuronal tumors are an expanding group of tumors with varying spectra of morphologic patterns and biological behavior. An improved understanding has direct clinical implications for optimizing current treatments and developing novel therapeutic approaches. Although most glioneuronal tumors carry a favorable prognosis, other factors such as inaccessibility to surgical resection and rarely, malignant transformation, make it difficult to accurately predict the biological behavior based on histopathology alone. Reliable prognostic markers remain to be defined.     

Medulloblastoma and gliomatosis cerebri: rare brain tumors in multiple sclerosis patients

The simultaneous appearance of both multiple sclerosis (MS) and central nervous system (CNS) tumors is relatively uncommon. Whether the co-existence of two diseases is due to chance alone or the result of a causal relationship is still a matter of debate. There is also controversy about the effect of long-term exposure of MS patients to immunomodulatory drugs on the incidence of cancer. This paper reports two cases of rare CNS tumors (i.e., medulloblastoma and gliomatosis cerebri) in adult MS patients. Our cases emphasize that when uncommon neurological features appear in patients with MS, brain magnetic resonance imaging (MRI) ought to be done and brain biopsy should be considered to exclude a concomitant CNS disorder. These procedures are essential for the differential diagnosis and early treatment.     

Meningiomas of the central nervous system occurring below the age of 17: report of 24 cases not associated with neurofibromatosis and review of literature

The objective of this work was to gain more insight into the controversial characteristics of meningiomas occurring during childhood and adolescence. Management of meningiomas is an important field in pediatric neurosurgery. Every pediatric neurosurgeon has tried to resolve the problems relating to the clinical characteristics, biological behavior and outcome of this interesting and almost benign pathology, which rarely occurs in the first two decades of life. The records on central nervous system (CNS) tumors held by the two major neurosurgery centers of Tehran Medical University and Arad General Hospital were prospectively collected during last 15 years. Complete medical records are available for all 24 cases, and long-term follow-up was achieved 19 patients. All the cases were diagnosed and treated after the introduction of computed tomographic (CT) scanning. Angiography and magnetic resonance imaging (MRI) were performed as complementary studies in some cases. The sample consisted of 13 girls and 11 boys. The age range at the time of diagnosis varied between 2 and 17 years, with a mean of 9.47 and standard deviation of 3.43. Fifteen patients were below 10 years of age (62.5%), and 9 of them were between 10 and 17 years old (37.5%). The most common presenting symptoms, in declining order of frequency, were headache, epilepsy and focal neurological deficits. Similar cases associated with neurofibromatosis either at the time of presentation with meningioma or during the follow-up period were excluded (5 cases). The size of the presenting tumor was more than 5 cm in diameter in 17 cases. The locations of the lesions, taken as the site of the presumed widest dural base in each case were: spinal, orbital, ethmoidal and sphenoethmoidal in 1 case each, petroclival in 2, and tentorial or supratentorial in 18 patients. The only predisposing factor in this series of childhood meningiomas was whole-axis irradiation for previous malignancy in the case presenting with cervical intradural meningioma. There have been no surgical deaths, and gross total excision of the lesions was achieved in 21 cases. Tumor recurrence was observed during the follow-up period in 6 cases (25%). The follow-up period varied between 2 and 165 months, with a median interval of 130.2 months. This series of pediatric CNS meningiomas comprises almost 1.08% of all meningiomas operated on by the authors during the last 15 years and it also accounts for about 1.1% of all pediatric CNS tumors encountered. This series of patients has certain characteristics regarding sex distribution, unusual size, peculiar localizations, special histological features and benign clinical behavior distinguishing it from other series reported in the literature. Received: 15 February 1999 Revised: 18 July 1999     

Treatment of primary central nervous system lymphoma in the immunocompetent patient

The incidence of primary CNS lymphoma (PCNSL), which has considerably increased these last years, remains stable in the immunocompetent population, while it is steadily decreasing in the immunosuppressed population. The addition of high dose methotrexate (MTX) based chemotherapy (CT) before whole brain radiotherapy (WBRT) has clearly improved the prognosis of PCNSL with a median survival of three to four years. About 30% of the patients may hope to have a long survival and to be cured. In the elderly (age over 60 years) CT alone (without RT) is recommended as initial treatment. This approach seems useful to avoid RT and to reduce the risk of delayed neurotoxicity due to the combined treatment. In the young population (age less than 60 years), intensive chemotherapy followed by hematopoietic stem cell rescue (ICH) appears as a promising approach in recurrent tumors and potentially as an alternative option to RT as consolidation treatment in newly diagnosed patients. A prospective trial will be activated in France soon randomizing ICH and RT in the initial treatment of PCNSL.     

Central nervous system involvement in Von Hippel-Lindau disease

Fifty individuals with Von Hippel-Lindau disease (VHL) were studied with gadolinium-enhanced magnetic resonance imaging (MRI) to determine the frequency and distribution of CNS lesions. The associated clinical features were also reviewed. Thirty-six (72%) of the 50 had 1 or more CNS tumors. The most frequently affected sites in the CNS excluding the retina were the cerebellum (52%), spinal cord (44%), and brainstem (18%). New regional predilections for the craniocervical junction and conus medullaris were demonstrated by this study. Forty-one percent of all VHL patients with CNS tumors were neurologically asymptomatic: cerebellar tumors (50%), spinal cord tumors (50%), and brainstem tumors (44%) were often without clinical signs or symptoms. Multiple lesions were common. The mean age of all VHL patients (34.5 years) was similar to the mean age of all CNS VHL patients (34.4 years), suggesting a lack of age association. CNS lesions commonly occurred in the 2nd decade of life. All patients at risk for VHL should be evaluated using gadolinium-enhanced MRI after 10 years of age, although ophthalmic examination should be initiated within the 1st 2 years of life. Enhanced MRI is particularly useful in the detection of CNS tumors in patients with the VHL gene.     

Febrile convulsions in a Serbian region: a 10-year epidemiological study

The first population-based study in the central region of the Republic of Serbia (total population 283,103) was carried out to assess some epidemiological features of febrile convulsions among children of between 6 months and 5 years of age. During the 10-year period, 1986 to 1995, there were 570 cases of the first febrile convulsions (287 males and 283 females). The average annual incidence rate was 3/1000 (2.9/1000 in males and 3.0/1000 in females), with the highest in 1995. During the study period, a significantly increased linear regression trend was observed. During the follow-up period of 5 years for children who had their first febrile convulsions in 1989 and 1990 (total 154 cases), 27 (17.5%) had a recurrence of the disorder, and ten (6.5%) had one or more afebrile seizures, of whom seven children (4.5% of total sample) developed epilepsy (recurrent afebrile seizures).     

Average years of potential life lost in those who have died from brain and CNS tumors in the USA

The aim of this study was to quantify the impact of all primary malignant and nonmalignant brain and central nervous system (CNS) tumors on mortality in the USA in terms of years of life lost, an indicator of premature mortality in the population. In this study, US mortality data for the year 2001 from the National Center for Health Statistics and life tables from the US Census Bureau were used. Person-years of potential life lost (PYPLL) and average years of potential life lost (AYPLL) were calculated for all deaths due to brain and CNS tumors as an underlying cause. 16,819 deaths due to brain and CNS tumors occurred in 2001, leading to a total loss of 357,483 person-years of life and an average loss of 21.3 years (AYPLL). Hispanic men and women had an AYPLL of 31.7 and 33.9 years, respectively, a figure substantially higher than other race and ethnicity categories. Malignant tumors led to an AYPLL of 25 years, which was significantly higher than the AYPLL of 19 years due to nonmalignant tumors. The relative impact of tumors arising in the various anatomical sites in the brain and CNS among adults and among children was not similar. The use of population survival indicators, such as PYPLL and AYPLL, will help better understanding of the effect of racial, ethnic, gender and age differences on the mortality due to malignant and nonmalignant brain and CNS tumors. Information on years of life lost, as well as mortality data, will be useful in focusing research priorities and resources in this field.     

Incidence and prevalence of motor neuron disease in two Danish counties

A total of 186 cases of motor neuron disease (MND) was identified in two Danish counties during the period 1974-1986. The average annual incidence rate was 1.4/100,000 population, and the male:female ratio of incidence rates was 1.5. Mean age at diagnosis was 64.3 +/- 10.0 years. The incidence rates increased significantly with advancing age and reached a maximum at age 60-79 years, followed by a nonsignificant decrease. The average point prevalence was 3.1/100,000 population. Bulbar symptoms were part of the initial symptoms in 65% of cases, and patients with bulbar onset were older than patients with spinal onset. Age- and sex-specific incidence rates indicated a marked male preponderance amongst the youngest patients, in contrast to a female preponderance in patients above 60 years with bulbar onset of MND. Familial MND accounted for 2.7% of cases.     

Brain tumors in Yamaguchi Prefecture--incidence through 4 years

The incidence of brain tumors was studied in Yamaguchi prefecture of about 1,600,000 population. All of the brain tumor patients admitted to the neurosurgical hospitals in Yamaguchi prefecture were registered. Cases of osteoma, lipoma, scalp tumor and spinal tumor were excluded. From 1986 through 1989, 726 cases were registered. 135 recurrent cases were included. Therefore first-diagnosed primary brain tumors were selected to calculate the true incidence. The number of cases of primary brain tumor was 478 and showed female preponderance (male/female: 207/271). The incidence of primary brain tumor was 7.5/100,000/year (male/female: 6.8/8. 1). No difference was present between the incidence in cities and that in rural districts. Percentages of representative tumors were 28.2% for glioma, 32.8% for meningioma, 13.0% for pituitary adenoma and 10.7% for neurinoma. Age-adjusted incidence was 2.1/100,000/year for glioma and 2.1/100,000/year for meningioma. The incidence of glioma was lower and that of meningioma was higher in Yamaguchi prefecture than those in other reports. Compared with the Brain Tumor Registry of Japan (1969-1983), the percentage of meningioma cases was large in Yamaguchi prefecture. This difference owed partly to the increased number of population over age of 40's in Yamaguchi prefecture. The peak of age distribution was present in age of 50's in Yamaguchi prefecture and in age of 30's and 40's in Brain Tumor Registry of Japan. The peak of age distribution shifted to older ages in Yamaguchi and the difference was conspicuous in age of 60's. This peak consisted of mainly cases of meningioma and partly those of glioma.(ABSTRACT TRUNCATED AT 250 WORDS)     

Dandy-Walker syndrome: incidence in a defined population of Tabuk, Saudi Arabia

Dandy-Walker syndrome (DWS) is characterized by cystic dilatation of the 4th ventricle and absence of the cerebellar vermis. There may also be posterior fossa enlargement, hydrocephalus, hypoplastic cerebellar hemispheres and other malformations within and outside the central nervous system (CNS). The condition is uncommon, and the incidence is unknown. We studied the incidence of DWS in a defined Saudi Arabian population of military personnel and their dependants. We identified all patients diagnosed with DWS during an 11-year period (1989-1999) from a cohort of 45,274 live births. The incidence of DWS was 1.0 per 100,000 live births per year. The incidence by sex per 100,000 live births per year was 1.24 for males and 0.78 for females. DWS formed 3.5% of our cases of infantile hydrocephalus.