The Relationship Between Light Reflex In Pupil And Intracranial Pressure: A Study Based On Portable Pupilometer Monitoring

The intracranial pressure（ICP）is the force acting inside the skull by cranial contents.Under normal circumstances,the ICP of an adult ranges from 0.7kPa（5mmHg）to 2.0kPa（15mm Hg）in lateral position,and from 0.5kPa（3.5mmHg）to1.0kPa（7.5mmhg）for a child.In pathological conditions,the increased ICP would occur,which is one of the most common symptoms in neurology and neurosurgery.It could be incurred by cerebral trauma,intracranial tumors,hydrocephalus,as well as intracranial infection.The intracranial contents would therefore expand in volume,rendering the ICP of 2.0kPa（200mmH₂0）and up,and cause possible symptoms.The cerebral hernia would be incurred when the ICP is far exceeding the compensative capacity,followed by respiratory and（or）circulatory failure.The idea of the ICP monitoring is to place sensors inside the lateral cerebral ventricle or frontal area,making the values of ICP accessible to the monitoring devices.Accordingly,the intracranial state of a patient could be accessed,so that therapeutic regimen and prognosis could be delivered.The pupillary light reflex（PLR）is a reflex that controls the diameter of the pupil,in response to the intensity（luminance）of light,which is a significant indicator of neurological examination.This research is based on a dynamic measurement of PLR by applying the advanced portable model of pupilometer,seeking for the connection between PLR indications and the fluctuation of the ICP,and hypothesizing a non-Invasive Intracranial Pressure monitoring.This research will collect the ICP data of patients with intracranial pressure probe implantation:15 cases each of brain parenchyma and ventricle implantation.At the same time,the PLR data is dynamically grabbed.All data is analyzed by using SPSS16.0.This research is seeking to 1)achieve dynamic measurement of the PLR by adopting a new model of pupilometer,offering an example for pupilometrics;and 2)discuss the statistical relevance between the PLR and the ICP based on the hypothetical non-Invasive Intracranial Pressure monitoring.This research proves the connections between the PLR and the ICP with the help of the newly designed pupilometer,and comes up with the idea of non-Invasive Intracranial Pressure Monitoring.In the future,ICP monitoring integrated with nervous system examination is highly achievable if assisted with ancillary techniques,and shows clinical applying foreground.