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Pre-Chiasmatic, Single Injection of Autologous Blood to Induce Experimental Subarachnoid Hemorrhage in a Rat Model
Published on: June 18, 2021
Axonal damage and outcome in subarachnoid haemorrhage
1Department of Neuroimmunology, Institute of Neurology, The National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK. a.petzold@ion.ucl.ac.uk
Journal of Neurology, Neurosurgery, and Psychiatry
|May 18, 2006
Summary
Axonal degeneration, indicated by elevated neurofilament heavy chain (NfH) levels in cerebrospinal fluid, is common in subarachnoid hemorrhage (SAH) patients and linked to poor outcomes.
Area of Science:
- Neuroscience
- Neurology
- Biomarker Research
Background:
- Subarachnoid hemorrhage (SAH) may involve underestimated axonal degeneration.
- Preliminary evidence suggests axonal damage is a significant pathological feature in SAH.
Purpose of the Study:
- To investigate the presence and significance of axonal degeneration in patients with aneurysmal SAH.
- To correlate levels of a specific biomarker for axonal damage with patient outcomes.
Main Methods:
- A longitudinal study of 17 aneurysmal SAH patients.
- Daily cerebrospinal fluid (CSF) collection for up to 14 days.
- Quantification of neurofilament heavy chain (NfH(SMI35)) using ELISA; Glasgow Outcome Score (GOS) assessed at 3 months.
Main Results:
- Pathologically high NfH levels were found in 52.7% of SAH patient CSF samples, versus 5% in a reference population.
- All patients with poor outcomes (GOS 1-3) showed increased NfH, compared to 8% with good outcomes (GOS 4-5).
- Increased NfH levels correlated with injury severity (WFNS, GCS) and inversely with GOS, becoming significant around 7 days post-hemorrhage.
Conclusions:
- Patients with SAH experience secondary axonal degeneration.
- This axonal degeneration may negatively impact patient outcomes.
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