Journal article
Characterising cerebrovascular reactivity and the pupillary light response-a comparative study
- Abstract:
-
Introduction: Smooth muscle is integral to multiple autonomic systems, including cerebrovascular dynamics through vascular smooth muscle cells and in ocular muscle dynamics, by regulating pupil size. In the brain, smooth muscle function plays a role in cerebrovascular reactivity (CVR) that describes changes in blood vessel calibre in response to vasoactive stimuli. Similarly, pupil size regulation can be measured using the pupillary light response (PLR), the pupil’s reaction to changes in light levels. The primary aim of this study was to explore the interplay between cerebral blood flow and pupil dynamics, evaluated using CVR and PLR, respectively.
Methods: A total of 20 healthy adults took part in a CVR gas stimulus protocol and a light and dark flash PLR protocol. CVR was calculated as the blood flow velocity change in the middle cerebral artery, measured using transcranial Doppler ultrasound in response to a 5% increase in CO2. Multiple PLR metrics were evaluated with a clinical pupillometer.
Results: CVR and PLR metrics were all within the expected physiological ranges for healthy adults. Nine different PLR metrics, assessed through the light and dark flash protocols, were compared against CVR. A significant negative relationship was observed between the latency of the PLR in the dark flash protocol and CVR. No statistically significant relationships were found between CVR and other PLR metrics.
Conclusion: This is the first study to investigate the relationship between cerebral blood flow and pupil dynamics. A significant relationship between dark flash latency and CVR was observed. Future work includes evaluating these relationships using more robust CVR and PLR measurement techniques in a larger, more diverse cohort. Notably, more research is warranted into the PLR using a dark flash protocol and its connection to cerebrovascular function.
- Publication status:
- Published
- Peer review status:
- Peer reviewed
Actions
Access Document
- Files:
-
-
(Preview, Version of record, pdf, 2.0MB, Terms of use)
-
- Publisher copy:
- 10.3389/fphys.2024.1384113
Authors
- Funder identifier:
- https://ror.org/0439y7842
- Grant:
- EP/S021507/1
- Publisher:
- Frontiers Media
- Journal:
- Frontiers in Physiology More from this journal
- Volume:
- 15
- Article number:
- 1384113
- Place of publication:
- Switzerland
- Publication date:
- 2024-08-08
- Acceptance date:
- 2024-07-29
- DOI:
- EISSN:
-
1664-042X
- Pmid:
-
39175613
- Language:
-
English
- Keywords:
- Pubs id:
-
2022625
- Local pid:
-
pubs:2022625
- Deposit date:
-
2024-09-30
- ARK identifier:
Terms of use
- Copyright holder:
- Sparks et al
- Copyright date:
- 2024
- Rights statement:
- © 2024 Sparks, Hayes, Pinto and Bulte. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
- Notes:
- This work is related to the thesis Models and methods of cerebrovascular reactivity mapping.
- Licence:
- CC Attribution (CC BY)
If you are the owner of this record, you can report an update to it here: Report update to this record