"Deep Brain Stimulation of the Ventral Intermediate Nucleus of the Thalamus for Tremor in Polr3a-Related Tremor-ataxia Syndrome: A Two-case Report".

CLINICAL VIGNETTE: RNA polymerase III subunit A (POLR3A) related disorders are a group of heterogeneous diseases with a recessive autosomic inheritance. These disorders manifest with distinct clinical features like ataxia, spasticity, hypodontia, hypogonadism, mental retardation and progressive motor decline.

CLINICAL DILEMMA: POLR3A gene mutation can manifest with parkinsonism, dystonia, ataxia and tremor. Deep brain stimulation (DBS) might be effective for motor symptoms. Choosing the best DBS target is essential for successful treatment.

CASE REPORTS AND CLINICAL SOLUTION: Two subjects with a predominant tremorous syndrome due to POLR3A gene mutation with no response to pharmacological treatment underwent DBS at ventral intermediate nuclei (Vim DBS) of thalamus, with significant improvement in tremor.

GAP IN KNOWLEDGE: Tremor in POLR3A gene mutation could respond to Vim DBS.