Evaluative effects of flash visual evoked potential on the changes of intracranial pressure

Jiying ZHOU; Jianping JIA; Lei WANG; Yongbo ZHANG; Guoguang PENG

ABSTRACT

BACKGROUND:

Flash visual evoked potential(fVEP) can reflect the integrity of visual pathway from retina to pulvinar cortex. The utilization of its characters can accurately evaluate the injury situation of visual conduction pathway.

OBJECTIVE:

To investigate the feasibility and effects of fVEP on non-traumatic monitoring of intracranial pressure.

DESIGN:

A repeated measurement design based on patients.

PARTICIPANTS:

Totally 197 patients with brain injury including 138males and 59 females with an average of(38 ±9) years old were selected from the First Affiliated Hospital of Chongqing Medical University and Xuanwu Hospital Affiliated to Capital University of Medical Sciences. The selected diseases were epidural hematoma( n=20),subdural hematoma(n = 26),cerebral contusion( n = 4),subdural hematoma companied with cerebral contusion( n = 92),and cerebral contusion companied with intracerebral hematoma( n = 55).

METHODS:

The level of intracranial pressure of 197 patients with brain trauma was detected with fVEP and epidural manometry. Data of traumatic surveillance were collected after the completion of fVEP. Changes of blood pressure and heart rate in patients were recorded simultaneously.MAIN OUTCOME

MEASURES:

fVEP results,and levels of intracranial pressure.

RESULTS:

The average intracranial pressure of 197 patients with brain trauma was(2.75 ± 0.64) kPa,( 1.54 - 4. 02 kPa) . The dispersion of both traumatic and non-traumatic surveillance was relatively big in patients with confirmed visual pathway injury. No typical wave was induced by fVEP in2.79% of patients. Scatter diagram suggested that the consistence between fVEP and epidural manometry was relatively good. Linear regression analysis showed that heart rate was the most sensitive one to the fluctuation of intracranial pressure (β = -0. 369) followed by systolic pressure (β= 0. 316),while diastolic pressure was not so sensitive (β = 0. 147). There was negative correlation between heart rate and intracranial pressure,which could quite sensitively reflect the fluctuation of intracranial pressure,systolic pressure was the next,and diastolic pressure was not easily to be affected by the changes of intracranial pressure.

CONCLUSION:

Non-traumatic surveillance,fVEP,has favorable consistence with traumatic detection,which can quantitatively evaluate the changes of intracranial pressure non-traumatically.