KAWAMATA Tatsuro NIHON UNIVERSITY SCHOOL OF MEDICINE DEPARTMENT OF NEUROSURGERY,INSTRUCTOR, 医学部(脳神経外科学), 助手 (20234122)
YAMAMOTO Takamitu NIHON UNIVERSITY SCHOOL OF MEDICINE DEPARTMENT OF NEUROSURGERY,ASSISTANT PROFESS, 医学部(脳神経外科学), 講師 (50158284)
KATAYAMA Youichi NIHON UNIVERSITY SCHOOL OF MEDICINE DEPARTMENT OF NEUROSURGERY,PROFESSOR, 医学部(脳神経外科学), 教授 (00125048)
|Budget Amount *help
¥6,600,000 (Direct Cost : ¥6,600,000)
Fiscal Year 1995 : ¥800,000 (Direct Cost : ¥800,000)
Fiscal Year 1994 : ¥5,800,000 (Direct Cost : ¥5,800,000)
Vegetative state has given a definition of hopless condition and American Neurological Association recommenmded to take out life-surporting treatments for the treatment of vegetative state patients in 1989. But on only 3-7% of them, spontaneously recovery from such hopeless state has been observed and some treatments like a transmitters administration and sensory stimulation therapy have been applied with some effects.
At this situation, the most important thing to make clear is (1) setting up the severity grade of vegetative state and (2) getting some informations about mechanisms of the effectiveness of treatments, in order to know phathogenesis and to predict the effect of the treatment.
In this study, the severity grade of the vegetative state patients is classified three grade ; complete type, incomplate type and transitional type, by neurobehavioral score which is evaluated by cognitive tests. On the cases evaluated transitional type or incomplate type, spectral EEG shows a changea
ble pattern, N20 wave of somatosensory evoked potential is recordable and fifth wave of auditory brainstem responses is also able to record. On complete type patients, these neurophysiological responses are always incomplete. And there is a difference of an amplitude of cognitive pain related late potenial (P250) between incomplate and transitional type. But it is difficult to know severity of vegetative state by measuring of the transmitters in CSF,to check regional cerebral blood flow and metabolism which are remakably increased following some treatments.
As a treatment for vegetative state patients, chronic deep brain stimulation has been applied in this study. Stimulation target is selected the center median nucleus of the thalamus or brainstem reticular formation and recently the Meynert nucleus is selected as second target according to this study on acetylcholine.
According to analysis of the follow up results of our clinical deep brain stimulation therapy, 35% of treated vegetative patients could recover from the hopeless state, and 72% of the treated transitional type and 45% of incomplate type had a chance to recover. The good recovered patients showed more than 10muV amplitude of P250.
It is concluded that there are some treatable vegetative state treated by using of chronic deep brain stimulation therapy, if they are incomplate or transitional type who have changeable EEG pattern, N20, and the fifth wave of auditory brainstem evoked potential and more than 10muV of amplitude of P250. Less