Dc-eeg for Routine Clinical Use: Methods and Clinical Impact
Traumatic brain injuries were analysed clinically and experimentally by recording stationary potential(SP) which is a very stable component in the electrical phenomena of the brain. SP value is considered to change positively or negatively only when there are organic lesions, severe metabolic changes of the brain, or epileptic seizures.<BR> Clinically, we have measured the SP of 103 head-injured patients. When an organic lesion was located in the cerebral hemisphere, the SP showed various changes according to the location of the lesion.<BR> Positive SP changes were usually seen in the cases of mild cortical compression and sub cortical lesions. Clinically, these lesions included epidural hematoma, subdural hematoma without contusion, chronic subdural hematoma, simple depressed fracture and intracerebral hematoma without cortical damage.<BR> Whereas, almost all of the cortical lesions or extensive brain lesions showed negative changes of SP. They were such as cerebral contusion, intracerebral hematoma with vascular lesion, depressed fracture with cortical damage and traumatic epilepsy.<BR> Subsequently, to support these clinical data, experimental cortical compression with clot inserted into subdural and extradural space, subcortical lesion by artificial intracerebral hema toma, cerebral contusion by mechanical destruction were investigated in cats. The experimental results showed the same tendency as the clinical data.<BR> In another experimental study, clarification of the possibility of SP change in concussion was attempted.