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Coma from worsening spontaneous intracranial hypotension after subdural hematoma evacuation
Amandeep K Dhillon1, Alejandro A Rabinstein, Eelco F M Wijdicks
1Division of Critical Care Neurology, Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
Background:
Low cerebrospinal fluid volume is typically diagnosed in patients presenting with positional headaches. However, severe intracranial hypotension and brain sagging may cause orthostatic coma. We present a case that illustrates this uncommon presentation.
Method:
Case report.
Results:
A 50-year-old man presented with orthostatic headaches and then developed bilateral subdural hematomas. Following unilateral subdural hematoma evacuation, the patient became gradually drowsier and more confused. Upon transfer to our hospital, he would become comatose each time he was placed in the upright position. Successful epidural patch at the level of a spontaneous cerebrospinal fluid leak documented by myelography resulted in complete resolution of his orthostatic symptoms despite reaccumulation of the subdural fluid collection.
Conclusions:
Evacuation of subdural fluid collections may be detrimental in patients with low CSF volume by exacerbating the intracranial hypotension. Extreme brain sagging may lead to anatomical distortion of the diencephalon and brainstem resulting in coma.
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