What are the key clinical features that suggest a diagnosis of Chiari malformation in a patient presenting with headache?

Key clinical features suggesting Chiari malformation in a patient presenting with headache include:

• Headache that is typically occipital or suboccipital in location, often exacerbated by Valsalva maneuvers such as coughing, sneezing, or straining.
• Associated symptoms may include neck pain, dizziness, balance disturbances, and sometimes sensory or motor deficits due to brainstem or spinal cord compression.
• Neurological signs such as nystagmus, dysphagia, or limb weakness may also be present, reflecting brainstem involvement.
• Headaches related to Chiari malformation are often chronic and progressive, differing from primary headache disorders.
• In some cases, symptoms of cerebrospinal fluid (CSF) flow obstruction or spontaneous intracranial hypotension may coexist, complicating the clinical picture.

These features align with NICE guidance on recognising neurological conditions that warrant referral ¹, emphasising the importance of headache characteristics and associated neurological signs. The literature further clarifies that Chiari I malformation classically presents with occipital headaches worsened by Valsalva maneuvers and may include brainstem-related symptoms (Sclafani et al., 1991; Ciaramitaro et al., 2019). Additionally, recent studies highlight the overlap with CSF leak syndromes, which can mimic or exacerbate Chiari symptoms (Kumar et al., 2023).