1987 Fiscal Year Final Research Report Summary
Experimental and Clinical Studies on the Effectiveness of Crerbrovascular Reconstructive Surgery by Hemodynamic and Electrophysiological assessment
| Project/Area Number |
61480310
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Cerebral neurosurgery
|
|---|
| Research Institution | Kyoto University |
|---|
Principal Investigator |
MORITAKE Kouzo Department of Neurosurgery, Kyoto University Hospital, 医学部, 講師 (90093327)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
NAGASAWA Shiro Department of Neurosurgery, Kyoto University Hospital, 医学部, 助手 (10144370)
|
|---|
| Project Period (FY) |
1986 – 1987
|
| Keywords | Reconstructive cerebrovascular surgery / Transcranial Doppler / Evoked potentials / Local cerebral blood flow / Extra-intracranial bypass / Carotid endarterectomy / Somatosensory evoked potentials / 脳虚血 |
|---|
| Research Abstract |
In the experimental model of whole brain ischemia, EEG changed to isoelectric pattern at the relatively early stage in producing ischemia. As far as cortical components of SEP still remained, electrophysiological parameters recovered following recirculation. Once SEP and BAEP were both abolished, however, EEG and cortical components of SEP hardly recovered unless recirculation started in a few minutes.
In the model for brain stem ischemia, spontaneous cerebral electrical activities were maintained although EEG changed significantly. In the way of experimental procedures for making ischemia in the brain stem, changes of BAEP firstly developed both in amplitude and latency. Decrease in amplitude of SEP followed to BAEP changes but latency of SEP was unchanged. Finally both cortical and brain stem components of SEP were abolished. Recovery of SEP occurred in the inverse order and was completed in a few minutes after recirculation. BAEP may be more sensitive to the brain stem ischemia than SEP as a critical parameter for assessment of the functional reversibility. SEP, however, may be more useful in practice than BAEP as a monitoring method of the brain stem function.
The patients were 7 adults and 7 children who showed preoperative angiographic evidence of bilateral carotid occlusive lesions. The differences between peroperative and postoperative evoked potentials are investigated. Improvement of SEP, VEP and BAEP was found in 3 of 7 adults. Evoked potentials showed improvement more often in younger adults. In 5 of 7 children with "moyamoya disease", the amplitude of the early components of cortical SEP decreased on the operated side and increased on the nonoperated side. Improvement of VEP and BAEP was noted in 2 and 3 of 7 children respectively. These results suggest of effectiveness of extracranial-intracranial bypass.
|
