Reperfusion Models of Rat Middle Cerebral Artery Occlusion:Extracranial and Transcranial Methods

The author described a comparative study of 2 different experiemental methods of reperfusion models in rat;1) transcranial method(TC) and 2) extracranial method(EC). The transcranial method was performed by a direct approach to the middle cerebral artery(MCA) after temporozygomatic craniotomy in which a wire was hooked on the proximal portion of middle cerebral artery(MCA) and pulled it to make occlusion of MCA. For the extracranial method, a nylon surgical thread was inserted intraluminally along the internal carotid artery(ICA) to reach the anterior communicating artery. Recirculation of blood was accomplished by removal of the hook or of the thread after 4 hours occlusion of MCA. Two different models were subdivided into 4 chronological groups:pre-reperfusion, 30 minutes, 2 hours, and 48 hours after reperfusion. The differences were evaluated with morphometric analysis after neutral red(NR) or tetrazolium salt(TTC) staining. From the evaluation of initial ischemic area, the extracranial method showed a larger infarct volume as compared to the transcranial method(p=0.013). Mean value(SD) of infracted area of EC and TC were 28.7%(4.4%) and 14.4%(8.1%) respectively. Recovery from the initial ischemia after reperfusion was gradually achieved in both of two groups(p<0.05). The restoration of blood flow after reperfusion was more rapid in EC group and only 2 hours' reperfusion was enough to show no difference between two methods. In TC group followed by 48 hours' reperfusion, 40% of animals resulted in gross infarction of MCA territory as noted with TTC stain, most probably due to reperfusion failure. EC group showed only one such a case(12.5%). But this difference was not in the range of significance statistically. From a technical point of view, EC was more simple, needed less time since a craniotomy was not performed, and required no manipulation of the brain or any intracranial vessels. From these results the author concluded that the extracranial method is a more reliable and technically more manageable one to be used as a reperfusion model for investigating the focal cerebral ischemia.

A Consideration to Brain Tumor Registry in Korea

The information obtained from epidemiology of brain tumor provide the key to the natural history of brain tumors and could be used for many different things, among others, the planning of hospitals and hospital care facilities and working out the medical requirements for each region. To cope with changing needs in this field due to the application of medical insurance to all Korean citizens from July 1. 1989, the brain tumor registries of various countries were reviewed and suggestions were made about Korean Brain Tumor Registry that should be prepared in the near future.

A Case of Unusual Acoustic Neurinoma: Case Report

A case of cystic acoustic Neurinoma is reported. The Patient was 41 year old man with temporal lobe epilepsy. Computerized tomography disclosed a low density cystic mass at left cerebellopontine angle that extended to suprasellar cistern through tentorium. At operation, multiloculated cysts were found that looked like cysticercosis. Pathological examination revealed a typical neurilemmoma with Antoni A and B area that formed cyst wall.

A Clinical Analysis of Brain Tumors in Children

The authors performed a clinical analysis of 80 cases of pediatric brain tumors which were verified by surgical operation during 10 years from Sept. 1978 to Aug. 1987 in the Department of Neurosurgery, Korea University, Seoul, Korea. These tumors were divided according to modified WHO classification. The results were as follows: 1) The male to female ratio was 1.42:1. 2) The most common pediatric brain tumor was gliomas(48.7%), and followed by medulloblastome(17.5%), germ cell tumor(7.5%), craniopharyngioma(6.2%), meningioma(5.0%). 3) Supratentorial tumors(57.5%) were more frequent than infratentorial tumors(42.5%). 4) Headache and vomiting were the most common presenting symptoms and papilledema was the most common sign. 5) Hydrocephalus was developed at supratentorial(58.7%) and infratentorial(73.5%) region. 6) Postoperative mortality was 7%.

A Clinical Analysis of Brain Tumors in Children

The authors performed a clinical analysis of 80 cases of pediatric brain tumors which were verified by surgical operation during 10 years from Sept. 1978 to Aug. 1987 in the Department of Neurosurgery, Korea University, Seoul, Korea. These tumors were divided according to modified WHO classification. The results were as follows: 1) The male to female ratio was 1.42:1. 2) The most common pediatric brain tumor was gliomas(48.7%), and followed by medulloblastome(17.5%), germ cell tumor(7.5%), craniopharyngioma(6.2%), meningioma(5.0%). 3) Supratentorial tumors(57.5%) were more frequent than infratentorial tumors(42.5%). 4) Headache and vomiting were the most common presenting symptoms and papilledema was the most common sign. 5) Hydrocephalus was developed at supratentorial(58.7%) and infratentorial(73.5%) region. 6) Postoperative mortality was 7%.

Clinical Applications of Visual Evoked Potentials

Visual evoked potentials were elicited by flash in 29 patients with a variety of cerebral lesions and in 10 normal controls. In 12 patients with focal brain lesions, no wave form could be recorded in one side. Of the remaining 23 sides, the average P1 latency showed no difference from that of the normal controls. In 17 patients with diffuse brain lesions no wave form could be elicited in 12 sides. Average P1 latency of remaining 22 sides showed statistlcally significant difference from that of normal controls. In this study it appears that delayed P1 latencies are associated with diffuse cerebral lesions rather than with localized lesions.