Background Central positional nystagmus represents a posterior fossa disorder of the vestibular system, and its clinical diagnosis remains a challenge for acute medicine and neurology.
Methods We performed a systematic literature search according to the Preferred Reporting items for Systematic Reviews and Meta-analysis (PRISMA) to identify the key clinical features and radiological findings of central positional nystagmus.
Results A total of 66 patients from 21 studies met the PICOS criteria for inclusion to this review. Five types of central positional nystagmus were identified during positional testing: horizontal nystagmus (30%), positional down-beating nystagmus (pDBN) (32%), pure torsional (8%), up-beating nystagmus (UBN) (5%), and a combination of the four profiles (33%). Vertigo was present in 36 patients (55%) and 17 patients (26%) complained of other symptoms, such as muscle weakness (23.5%), headache (23.5%) and gait disturbance (17.6%). Radiologically, 42 patients (63%) had cerebellar involvement, four patients had isolated brainstem lesions (6%), and 10 patients (15%) had lesions involving the IVth ventricle.
Conclusions Key clinical characteristics that help distinguish central from peripheral positional nystagmus are discussed. A formulation of the mechanism underlying CPN will allow the translation of descriptive neurological investigation into therapeutics, but this requires fuller understanding of the clinical syndromes.