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Improved Method for the Preparation of a Human Cell-based, Contact Model of the Blood-Brain Barrier
Published on: November 12, 2013
Phenytoin penetration into chronic subdural haematomas
A C Iplikçioğlu1, M Z Berkman, S Bek
1Department of Neurosurgery, Social Security Okmeydani Teaching Hospital, Istanbul, Turkey. acelal@doctor.com
British Journal of Neurosurgery
|March 26, 2004
Summary
Exudation from chronic subdural hematoma (CSH) membranes may cause enlargement. Measuring phenytoin levels in CSH quantifies this exudation, aiding understanding of CSH pathophysiology.
Area of Science:
- Neurosurgery
- Neurology
- Pathophysiology
Background:
- The exact mechanisms driving chronic subdural hematoma (CSH) enlargement remain incompletely understood.
- Recent research suggests exudation from macrocapillaries within the CSH outer membrane may be a key factor.
Purpose of the Study:
- To investigate the role of exudation in CSH enlargement.
- To establish a method for quantitatively assessing this exudation.
Main Methods:
- Phenytoin, an antiepileptic drug, was administered intravenously to 22 CSH patients.
- Blood and CSH fluid samples were collected 1 hour post-administration.
- The ratio of phenytoin concentration in CSH fluid to blood (phenytoin penetration ratio - PPR) was calculated.
Main Results:
- The mean PPR was 19.5%, indicating significant phenytoin penetration into CSH.
- Higher PPR correlated with increased neurological severity (Markwalder and GCS grades).
- PPR was higher in older patients (>60 years), high-density CSH on CT, and cases with subdural reaccumulation.
Conclusions:
- Exudation from CSH macrocapillaries likely contributes significantly to CSH enlargement.
- Measuring phenytoin levels in CSH provides a simple, quantitative method to assess exudation, aiding CSH research and management.
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