# Deep Brain Stimulation for Medication Refractory Tremor in Leber Optic Neuropathy Plus Syndrome

## TL;DR

A man with a rare mitochondrial disorder and treatment-resistant tremors saw significant improvement after deep brain stimulation.

## Contribution

First successful treatment of essential tremor in LHON-plus using deep brain stimulation.

## Key findings

- Bilateral deep brain stimulation improved refractory tremors in a patient with LHON-plus.
- Standard medications failed to control the patient's tremors before DBS was used.
- This case suggests potential for DBS in treating tremors associated with LHON-plus.

## Abstract

Leber hereditary optic neuropathy (LHON) is a mitochondrial disorder that presents with acute to subacute onset of unilateral progressive optic neuropathy, with sequential involvement of the fellow eye months to years later. The condition may be accompanied by neurological symptoms, including tremors, dystonia, seizures, or psychosis, in which case, it is termed LHON-plus. Here, we present the case of a 53-year-old man who was initially diagnosed with essential tremor but was later found to have LHON-plus after the onset of bilateral visual loss and a genetic panel. His essential tremor was refractory to standard pharmacological therapies, including propranolol, primidone, and topiramate. As a result, he elected to undergo bilateral deep brain stimulation (DBS) of the bilateral ventral intermediate nucleus of the thalamus with a dramatic improvement in symptoms. To our knowledge, this is the first case of essential tremor presenting in the context of LHON-plus to be treated successfully with DBS. While DBS has been applied in LHON-plus presenting with dystonia with limited success, our outcome suggests that there is promise in this approach and that more research is needed to evaluate it.