Late onset of cervical dystonia in a 39-year-old patient following cerebellar hemorrhage

Abstract

Cervical Dystonia (CD) is the most common form of focal dystonia with an incidence of 8.9 per 10,000 people [9]. The majority of cases are idiopathic, and secondary CD is associated with perinatal, vascular, traumatic, infectious and drug-induced processes affecting the central and peripheral nervous system [12]. A few reports have suggested that the cerebellum plays a role in pathogenesis of dystonia, There have been four cases in the literature describing CD that developed following a cerebellar stroke [2, 10, 11, 15]. We hereby present a rare case of CD developing 15 months after a cerebellar hemorrhage secondary to a ruptured AVM of the cerebellar vermis. A 37-year-old right-handed male presented to us with a sudden onset of headache, vomiting and dizziness. Neurological examination revealed right-sided horizontal nystagmus, ataxic gait, right-sided dysmetria and difficulty with finger nose test. His previous medical history and family history were unremarkable. An emergency noncontrast computerized tomography scan revealed a 2.4 9 1.6 cm hemorrhage in the vermis and in the occipital horns of the lateral ventricles. Magnetic Resonance Imaging (MRI) revealed an arteriovenous malformation (AVM) with venous varices in the cerebellar vermis (see Fig. 1). The AVM was embolized using ONYX and surgically excised 3 months later. After treatment, his cerebellar gait ataxia and dysarthria slightly worsened over the next 1 year. Fifteen months after the cerebellar hemorrhage, the patient developed intermittent rotational torticollis towards the left without trauma or exposure to dopamine blocking drugs. Primidone, topiramate, alprazolam, cyclobenzaprine, NSAIDs and physical therapy failed to provide relief. The patient received injections of Botulinum toxin type A (BOTOX ) to cervical muscles with a significant improvement. We believe that our case represents the fifth report of CD following a cerebellar stroke and the first one following a cerebellar hemorrhage. Alarcon et al. [2] performed a study in Ecuador on 56 patients with movement disorder after stroke. One of these patient had suffered a cerebellar ischemic stroke and developed dystonia 2 months later. Zadro et al. [15] described another patient who developed right-sided rotation of the head on the second day after having a left-sided cerebellar ischemic stroke. O’Rourke et al. [10] described a patient who developed paroxysmal CD following bilateral cerebellar infarction. Rumbach et al. [11] described a case of cerebellar infarction following vertebral artery occlusion who developed hemidystonia 2 months later. It is noteworthy that in our case CD developed after a substantially longer latency of 15 months. Other authors have also described CD in patients with space-occupying lesions (see Table 1) [1, 3, 6–8, 13, 14]. N. Usmani C. Sengun A. Pandey C. Singer Department of Neurology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA