Background:
Thalamic stroke frequently presents with contralateral sensory deficits. However, incomplete hemisensory presentations such as Cheiro‑Oral Syndrome (COS) and Cheiro‑Oral‑Pedal Syndrome (COPS) are under recognised. COS is characterised by paraesthesia or reduced sensation involving the perioral region and ipsilateral hand, while COPS includes additional involvement of the ipsilateral foot. These syndromes are most associated with small infarctions of the ventral posteromedial (VPM) and ventral posterolateral (VPL) thalamic nuclei. They are often provisionally interpreted as stroke mimics leading to delayed diagnosis and secondary prevention
Methods:
We conducted a retrospective case series of patients presenting to a primary stroke centre with sensory symptoms consistent with COS or COPS. Presenting symptoms, vascular risk factors, neuroimaging findings and stroke aetiology were analysed. A focused literature review was performed on thalamic sensory stroke syndromes emphasising neuroanatomical localisation and diagnostic challenges.
Results:
Six patients were identified through Transient Ischaemic Attack (TIA) clinic during 2025. Patients ranged from 58 to 79 years of age, with hypertension, dyslipidaemia, diabetes and smoking as common risk factors. Clinical presentations included COS and COPS patterns, often with fluctuating or stuttering symptoms. Magnetic resonance imaging (MRI) demonstrated acute infarcts localising to the lateral or posterolateral thalamus. The predominant aetiology was small vessel disease or atherosclerosis. Functional outcomes were favourable (modified Rankin Scale 0–1), although residual sensory symptoms were common.
Conclusion:
Cheiro‑Oral Syndrome and Cheiro‑Oral‑Pedal Syndrome are well defined, but under recognised presentations of sensory thalamic stroke. Recognition may reduce misdiagnosis, reduce diagnostic delay, facilitate acute stroke management and secondary prevention.