Intracranial hypotension

Background

• Low pressure headaches caused by spontaneous intracranial hypotension
• Provoked (e.g. LP) or spontaneous (dural leak)
• Rare. Max 50yo ♀
• Risks: Minor trauma, Marfans, neurofibromatosis, polycystic kidney diesase

Clinical

• Worse by change in position particularly supine to upright
• Max minutes after standing, ↓↓with lying down
• Generalised headache, ± neck ache, N&V, ± tinnitus

Differential Dx

• Migraine
• Persistent daily headache

Investigations

• MRI with gadolinium = pachymeningeal enhancement & brain “sagging” (see post LP headache)
• Dx confirmed with LP opening pressure (<6cm water in lat. decubitus) - but .... beware worsening headache

Management

• Rehydration, simple analgesics
• Blood patch

Links