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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
Headache attributed to spontaneous intracranial hypotension.
Eliana Mea1, Luisa Chiapparini, Mario Savoiardo
1Department of Neurology Unit of Pain Neuromodulation Fondazione, Istituto Nazionale Neurologico Carlo Besta, Via Celoria 11, 20133 Milan, Italy.
Summary
Spontaneous intracranial hypotension (SIH) causes various headaches. Current International Headache Society criteria for headache attributed to SIH are not met by most patients, indicating a need for revision.
Area of Science:
- Neurology
- Neuroimaging
- Headache Medicine
Background:
- Spontaneous intracranial hypotension (SIH) is increasingly recognized, presenting with diverse headache types beyond orthostatic headache.
- The International Headache Society (IHS) proposed diagnostic criteria for headache attributed to SIH.
Purpose of the Study:
- To evaluate the applicability of the IHS diagnostic criteria for headache attributed to SIH in a cohort of diagnosed patients.
- To identify limitations in the current IHS criteria for classifying headaches in SIH.
Main Methods:
- Retrospective analysis of 70 patients diagnosed with SIH between 1993 and 2005.
- Diagnosis confirmed by brain-enhanced MRI.
- Application of the IHS (2004) criteria for "Headache attributed to SIH".
Main Results:
- All patients met imaging criteria (B and C) for SIH.
- A significant proportion of patients did not meet IHS criteria A (49%) and D (89%).
- Only 3% of patients fulfilled all IHS criteria, suggesting the criteria are insufficient for most SIH headache cases.
Conclusions:
- The current IHS diagnostic criteria for headache attributed to SIH are inadequate for classifying the majority of patients with SIH.
- A revision of the IHS criteria is necessary to accurately diagnose and manage headaches associated with SIH.
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