Benign Paroxysmal Positional Vertigo Diagnosed in a Patient with Idiopathic Cervical Dystonia

Idiopathic cervical dystonia (CD) is a focal dystonia characterized by involuntary contraction of the muscles of the neck causing twisting movements and abnormal head and neck postures. Its etiology is unclear; however, intracerebral neuronal circuit pathologies are highly considered. On the contrary, benign paroxysmal positional vertigo (BPPV) is the most common peripheral vertigo diagnosed. We present a patient with CD suffering from severe vertigo who was diagnosed with BPPV. This is a very unique case representing the co-occurrence of a rare central nervous system pathology and a peripheral inner ear disease. The cause and effect relation between two pathologies is under scope. We present a 55-year-old woman with CD attended our clinic with severe vertigo and nausea. Left posterior semicircular canal BPPV (PSCC BPPV) was diagnosed. Involuntary head and neck muscle contractions caused by CD appear to have contributed to the development of BPPV in this case. However, increased neuronal activities causing CD could also have led to BPPV in the vestibular nuclear level. Further investigations are essential. Peripheral vestibular pathologies and their association with CD are not clearly determined in the literature so far. To our knowledge, there are no other cases reported regarding this co-occurrence.