Dysgeusia in deep brain stimulation for essential tremor

Area of Science:

• Neurology
• Neurosurgery
• Sensory Perception

Background:

• Dysgeusia (foul taste) is a rare side effect of deep brain stimulation (DBS) in the thalamus for essential tremor.
• Understanding the incidence and characteristics of DBS-associated dysgeusia is crucial for patient management.

Purpose of the Study:

• To evaluate the incidence, nature, neurophysiological, and anatomical factors associated with dysgeusia following thalamic DBS for essential tremor.

Main Methods:

• Retrospective analysis of 52 patients with essential tremor who underwent DBS.
• Assessed dysgeusia incidence, characteristics, and lead locations via postoperative MRI.
• Compared lead locations between patients with and without dysgeusia.
• Utilized intraoperative microelectrode recording and sensory threshold testing.

Main Results:

• 15% (8/52) of patients reported dysgeusia, distinct from paresthesia.
• Dysgeusia was more common with bilateral DBS (22%) than unilateral (8%).
• Leads associated with dysgeusia were located more posteriorly in the thalamus (4.5 mm vs. 5.7 mm anterior to the posterior commissure, P < .001).
• Low sensory threshold for paresthesia predicted postoperative dysgeusia (1.5 V vs. 3.3 V, P < .05).

Conclusions:

• Thalamic DBS can alter taste perception, with posterior lead placement in the sensory thalamus implicated in dysgeusia.
• Dysgeusia incidence and severity may be influenced by lead laterality and location.
• Management strategies include adjusting stimulation parameters or surgical revision of leads.