Validity of pupillomtery and correlation with intracranial pressure
Research type
Research Study
Full title
Validity of quantitative pupillometry in neurocritical care and correlation with intracranial pressure: an observational, uni-institutional study
IRAS ID
259594
Contact name
Wisha Gul
Contact email
Sponsor organisation
The Walton Centre NHS Foundation trust
Duration of Study in the UK
0 years, 6 months, 1 days
Research summary
Traumatic brain injury (TBI) is a major cause of death and disability amongst young adults. Efforts to improve outcomes for these patients are urgently needed. TBI is assessed by clinical evaluation, brain scans and invasive monitoring of pressure build up in the brain (intracranial pressure (ICP)). Monitoring pupil size and its light reflex mechanism is an integral part of non-invasive clinical monitoring in patients with severe brain injury in intensive care units globally. The implications of detecting an abnormal response are widely established, indicating rising ICP and worsening neurological outcome. Given the crucial role of these parameters, there is considerable impetus to ensure they are measured accurately.
Conventionally, pupils are assessed using a handheld pen torch, where the examiner visually determines the size and reactivity of pupils as fixed/dilated/brisk/sluggish/nonreactive. The assessment is subjective and often applied in the absence of a standardised protocol. There is a potential to compound inaccuracies, considering the significant inter-observer variability. Whilst many advances in quantitative pupillometer devices have been developed, their use is limited to research settings. Recently, the advent of the portable, handheld pupillometer presents a unique opportunity to provide reliable and consistent assessments of an indispensable clinical parameter. It measures several factors including size, speed of constriction and dilation to provide a measure called the neuro-pupillary index (NPi).
Our study aims to compare the use of standard pen torch with the pupillometer device for pupil assessment in severely brain injured patients in the neuro-critical care unit (NCCU). This data would establish whether currently practiced pupillometry is inadequate for clinical practice. We also propose to study whether pupil response (NPi) changes with rising ICP. This has the potential to allow early, non-invasive detection of neurological deterioration and as such, indication for timely intervention in the first instance. It also allows scope for development of this tool across emergency departments and even pre-hospital care settings.REC name
North West - Greater Manchester South Research Ethics Committee
REC reference
19/NW/0453
Date of REC Opinion
17 Sep 2019
REC opinion
Further Information Favourable Opinion