To describe an atypical presentation of reversible cerebral vasoconstriction syndrome (RCVS) in a peripartum patient without initial headache.

RCVS is a transient vasculopathy associated with reversible cerebral arterial narrowing, most commonly triggered by pregnancy or vasoactive substances. It typically presents with thunderclap headache, but atypical cases may delay diagnosis.

A 26-year-old woman at 37 weeks gestation with type 1 diabetes presented with 24 hours of acute confusion and word-finding difficulty. She denied headache, sensory loss, focal weakness, and infectious symptoms. Examination showed impaired naming and calculation with intact motor and sensory function. Overnight, she developed visual hallucinations. Due to worsening encephalopathy and preeclampsia, she underwent an urgent C-section.

Postpartum, she remained confused with agitation, paranoia, and hallucinations. Initial MRI/MRA Brain and CSF studies were unremarkable. EEG showed generalized slowing. Infectious and autoimmune panels were negative. Over several days, she developed recurrent transient aphasia and encephalopathy, with witnesses noting head-clutching suggestive of pain. Repeat MRI revealed new multifocal acute infarcts involving basal ganglia, centrum semiovale, and subcortical white matter.

Vascular etiologies were prioritized. Hypercoagulability studies were normal. Diagnostic angiography showed diffuse small-vessel caliber irregularities consistent with postpartum vasculopathy. She was treated with calcium channel blockers and monitored with daily transcranial dopplers showing multifocal vasospasm. Motor and speech deficits resolved with rehabilitation. At six months, neuropsychological testing showed minimal cognitive deficits.

This case demonstrates that RCVS may present without headache in peripartum patients and mimic metabolic, autoimmune, or psychiatric conditions. Observation of nonverbal pain cues and repeat imaging were essential. This patient’s symptoms became worse with recurrence, whereas the majority of cases describe maximum symptoms at onset. Visual symptoms described with RCVS are typically cortical blindness or Balint syndrome, not hallucinations, which was a complicating factor in this case.