We reviewed wide varieties of literatures about pathophysiology of cerebral arteriovenous malformation. With author's experiences on cerebral arteriovenous malformation, we described about clinical presentation, mechanisms of neurologic symptoms, natural history, hemodynamics, and cerebral steal phenomenon.
Arteriovenous Malformations ; Hemodynamics ; Intracranial Arteriovenous Malformations ; Natural History ; Neurologic Manifestations

No abstract available.
Hemorrhage* ; Humans ; Movement Disorders*

Teratogenic effects of carbamazepine, an anticonvulsant, on the neurulation of the explanted early chick embryos were studied utilizing the punched-out filter paper explantation and culture technique. Fresh fertilized white leghorn hen eggs were incubated for 20-30 hours in an egg incubator. The Hamburger and Hamilton stage 4-11 chick embryos were explanted using the punched-out filter paper explantation technique and cultured in the CO2 cell culture incubator for 6-10 hours. They were randomly divided into a control group and an experimental group. The experimental group was divided into five subgroups according to the carbamazepine concentrations of 20micrometer 40micrometer 100micrometer 200micrometer 400micrometer with which the Ham's F-10 culture media were treated. The morphological characteristics and the incidences of teratogenic effects on the neurulation of early chick embryos in the control and experimental groups were compared with each other using the stereomicroscope and the electron microscope. The chick embryos of the same developmental stage were selected from the control and experimental groups, and immunohistochemical staining for fibronectin was done by the double-bridge PAP method. The results were as follows. 1) Of the 41 chick embryos cultured in the Ham's F-10 media without carbamazepine, 38 embryos(92.7%) developed normally, and 3 embryos(7.3%) developed abnormally. In contrast, among the 98 embryos cultured in the carbamazepine-treated media, 54 embryos(55.1%) developed abnormally. The frequent anomalous features were deformities of the neural folds, failure of neural tube closure, derangement of somites, and developmental arrest. 2) The frequency and severity of abnormal embryos increased in dose-dependent fashion. The embryos cultured in the media treated each with 20micrometer 40micrometer 100micrometer 200micrometer 400micrometer of carbamazepine developed abnormally in 12.5%, 21.1%, 60.0%, 81.0%, 86.4% respectively. 3) The scanning electron microscopic findings in neuroepithelial cells of abnormally developed embryos were flattened and smooth cellular surface with diminished surface blebs and microvilli, and size irregularity of the cells. On transmission electron microscope, underdevelopment of intracellular microfilaments was seen, but there was no significant change in the intracellular organelle. 4) The immunohistochemical stainability of the extracellular fibronectin at the basal side of the neuroepithelium was decreased in the carbamazepine-treated embryos.
Actin Cytoskeleton ; Animals ; Blister ; Carbamazepine ; Cell Culture Techniques ; Chick Embryo* ; Congenital Abnormalities ; Culture Media ; Culture Techniques ; Eggs ; Embryonic Structures ; Fibronectins* ; Incidence ; Incubators ; Microvilli ; Neural Crest ; Neural Tube ; Neuroepithelial Cells ; Neurulation* ; Organelles ; Ovum ; Somites

Teratogenic effects of a diphenylhydantoin on the neurulation of the explanted early chick embryos were studied using the punched-out filter paper explantation technique. The 6th to 9th Hamburger and Hamilton staged chick embryos were explanted and cultured in the Ham's F-10 media treated with 15 microgram/ml, 30 microgram/ml, 60 microgram/ml, 90 microgram/ml, 120 microgram/ml of diphenylhydantoin in the CO2 incubator for 6-9 hours. The morphological chracteristics and the ultrastructural changes of the neuroepithelium of early chick embryos were compared with the control and experimental group using the stereomicroscope and the electron microscope. Of th 40 chick embryos cultured in the Ham's F-10 media without drug, 37 embryos(92.5%) developed normally and 3 embryos(7.5%) developed abnormally in 94 embryos(61.4%). The frequent anomalous features of the embryos were deformities of the neural folds in the cranial regions, failure of neural tube closure, dispersion of somites and developmental arrest. The scanning electron microscopic findings of neuropithelial cells of abnormally developed embryos were diminished surface blebs and microvilli, flattened and smooth cellular surfaces, and irregular size of cells. The transmission electron microscopic findings of neuroepithelial cells of abnormally developed embryos showed no significant changes of the development of intracellular organelles except the smooth cellular surface and mild underdevelopment of microfilaments.
Actin Cytoskeleton ; Animals ; Blister ; Chick Embryo* ; Congenital Abnormalities ; Embryonic Structures ; Incubators ; Microvilli ; Neural Crest ; Neural Tube ; Neuroepithelial Cells ; Neurulation* ; Organelles ; Phenytoin* ; Somites

The authors report a case of recurrent expansile cyst formation after gamma knife radiosurgery(GKRS) for a cerebral arteriovenous malformation where the residual nidus might play an important role. A 28-year-old male patient underwent gamma knife radiosurgery for a left parietal lobe arteriovenous malformation which had manifested with generalized tonic-clonic seizure in November 1992. In March 1999, 76 months after GKRS, the patient presented with headache, dysphasia and right hemiparesis and the computed tomography(CT) and magnetic resonance(MR) image revealed a huge cystic lesion with enhancing nodule at the anterior wall of the cyst. Cerebral angiography showed a small residual nidus. Aspiration and drainage of the cystic fluid via a burr hole was performed and the symptoms improved. One year later, in March 2000, the symptoms recurred, and CT and MR image revealed a new huge cystic lesion anterior to the enhancing nodule. Surgical removal of the residual nidus was performed, and there is no recurrence of the cyst for two years till now.
Adult ; Aphasia ; Arteriovenous Malformations ; Cerebral Angiography ; Drainage ; Headache ; Humans ; Intracranial Arteriovenous Malformations* ; Male ; Paresis ; Parietal Lobe ; Radiosurgery* ; Recurrence ; Seizures

No abstract available.
Aneurysm* ; Arteries* ; Cardiopulmonary Bypass* ; Circulatory Arrest, Deep Hypothermia Induced*

For better understanding and management of intracranial arteriovenous malformation(AVM), a retrospective clinical study was performed on 87 patients with intracranial AVM during the period from February 1980 to August 1986. The 54 patients managed conservatively and the 33 patients treated surgically were followed for an average of 13.7 months. Followings are the results : 1) The age range of presentation of intracranial AVM was 10 months to 52 years, with peak incidence from second to third decade. 2) The presenting symptoms were hemorrhage (51.7%), seizure (31%), and headache (6.9%) in order of frequency. In hemorrhage, intracerebral hematoma was most frequent and in seizure, generalized seizure was most frequent. 3) The location of intracranial AVM was hemispheric (71.3%), deep seated (17.2%), posterior fossa (8%), and dural location (3.5%) in order of frequency. 4) Concomitant aneurysm was found in 5 cases (5.7%). 5) In small intracranial AVM, 85% was presented with hemorrhage, and in large intracranial AVM, 59% with seizure. 6) The clinical outcome according to age was not different statistically between children and adults. 7) The incidence of rebleeding was 20% (9 of 45), and the mortality due to rebleeding was 22.2% (2of 9). 8) The clinical outcome for patients presenting with hemorrhage is worse than that for patients presenting with seizure. 9) The clinical outcome for patients managed surgical was more favorable than that for patients managed conservatively.
Adult ; Aneurysm ; Arteriovenous Malformations ; Cerebral Hemorrhage ; Child ; Headache ; Hematoma ; Hemorrhage ; Humans ; Incidence ; Intracranial Arteriovenous Malformations* ; Intracranial Hemorrhages ; Mortality ; Retrospective Studies ; Seizures

We report a long-term survival case of a primary malignant intracerebral nerve sheath tumor (MINST) occurring in the right frontal lobe of a 13-year old boy. After the gross total resection (GTR), we have performed radiation therapy but it recurred 50 months after the surgery, so the second GTR was performed. Later, second tumor recurrence was found 4 months after the second surgery. Subsequently the third GTR, radiotherapy, and chemotherapy were carried out. At present, the patient has been remaining alive for 77 months without evidence of tumor recurrence. According to the previous reports, the primary MINST is very rare : there are only 8 cases reported. It is also a fast-growing, invasive tumor with poor outcome. This is the first case that had no recurrence for 50 months after the surgery among the reported cases that had been followed up for more than 5 years. It is supposed that a period of recurrence free survival after GTR and low mitotic activity are associated with the patient's prognosis. A GTR followed by adjuvant radiation therapy and chemotherapy will be recommended to patients of MINST.
Drug Therapy ; Frontal Lobe ; Humans ; Prognosis ; Recurrence

Chick embryos have been used widely as model systems for studies in experimental embryology and teratology. Especially early chick embryos are very useful for studies of neural tube defects. We made a try to figure out the effect of Ca++ on neurulation using Ca++ antagonist and Ca++ free media in early chick embryo, which is stage 8 by Hamburger & Hamilton classification. After 6~9 hours incubation in media treated with verapamil and media without Ca++, we observed the effects of these agents by LM and EM. All of 12 embryos incubated in Ca++ free media showed that neural tube was diffusely opened along the whole axis and other deformity was not found. The chick embryos cultured in medium treated with verapamil revealed various abnormalities in dose related manner. The case of arrest of the growth was also observed, which was not found Ca++ free media group. On scanning electron microscopic examination, the surface of neuroepithelium was flattened in embryos cultured in Ca++ free media.
Animals ; Axis, Cervical Vertebra ; Chick Embryo* ; Classification ; Congenital Abnormalities ; Embryology ; Embryonic Structures ; Microscopy, Electron, Scanning ; Neural Tube ; Neural Tube Defects ; Neurulation* ; Teratology ; Verapamil

We report on a case of an 87-year-old woman who showed spontaneous resolution of a large chronic subdural hematoma which required surgical decompression. She had suffered from confused mentality and right side weakness of motor grade II for 10 days. The initial brain CT scan showed a 22 mm thick low density lesion located in the left fronto-temporo-parietal region with midline shift (12 mm) which required emergency decompression. However, because she and her family did not want surgery, she was followed up in the outpatient clinic. Five months later, follow up brain CT showed that the CSDH had disappeared and the patient became neurologically normal. The reasons for spontaneous resolution of CSDH remain unclear. We discuss the possible relation between mechanisms of physio-pathogenesis and spontaneous resolution of a large chronic subdural hematoma (CSH) in an elderly patient.
Aged ; Aged, 80 and over ; Ambulatory Care Facilities ; Brain ; Craniotomy ; Decompression ; Decompression, Surgical* ; Emergencies ; Female ; Follow-Up Studies ; Hematoma, Subdural, Chronic* ; Humans ; Tomography, X-Ray Computed