A 37 year-old male is seen in clinic. Around the age of 24, he started noticing stiffness in his legs. His balance also became affected over the years. He now complains of dysphagia. On examination, he has mild generalised chorea, limb dystonia, dysarthria, gait ataxia and oromandibular dyskinesia. MRI (axial T2 weighted, coronal T1, and axial SWI) of the brain is shown below. What is the most likely diagnosis?