Objective: To investigate the therapeutic effect of deep brain stimulation (DBS) on patients with NIID-related tremor.

Background: Neuronal intranuclear inclusion disease (NIID) is a rare, progressive neurodegenerative disorder characterized by the presence of eosinophilic intranuclear inclusions across multiple systems. While its clinical presentation is highly heterogeneous, movement disorders, particularly refractory head and limb tremors, can significantly impair the quality of life. Although deep brain stimulation (DBS) of the ventral intermediate nucleus (VIM) is a well-established intervention for essential tremor (ET), its therapeutic potential and safety profile for NIID-related tremor remain poorly explored.

Method: We performed a prospective analysis of three patients with clinically and genetically confirmed NIID. The mean age of onset was 49 ± 9 years, and the average disease duration at the time of surgery was 18 ± 5.57 years. All patients presented with severe, medication-refractory head or limb tremors and underwent bilateral VIM-DBS. Clinical outcomes were assessed at baseline and annual follow-ups using a comprehensive battery of scales: the Fahn-Tolosa-Marin Tremor Rating Scale (FTMTRS), the Tremor Assessment Group of the Movement Disorder Society (TETRAS) Performance and Activities of Daily Living (ADL) subscales, the Quality of Life in Essential Tremor Questionnaire (QUEST), and the International Cooperative Ataxia Rating Scale (ICARS).

Results: Significant clinical improvements were observed. The FTMTRS score decreased significantly from a baseline of 78.33 ± 7.09 to 39.00 ± 12.16 one year after the surgery (p=0.008). Consistently, TETRAS Performance and ADL subscales were also improved. In one patient, the QUEST score decreased by 70.59% (from 85 to 25) two years after surgery. No significant surgical complications or accelerated cognitive decline were observed during the follow-up period.

Conclusion: Bilateral VIM-DBS is an effective and durable intervention for managing severe tremors in patients with NIID. Despite the progressive nature of NIID, VIM-DBS significantly reduces tremor burden and improves quality of life. This study suggests that DBS should be considered a viable symptomatic treatment for NIID patients where tremor is the predominant cause of disability.

The changes in FTMTRS scores of the three patients

The changes in TETRAS-ADL of three patients

The changes in TETRAS-performance of 3 patients

References: 1. Sun Y, Lang L, Zhou X, Shen B, Hu J, Wu J. Bilateral deep brain stimulation of posterior subthalamic area in patient with spinocerebellar ataxia type 12. Mov Disord Clin Pract. 2024;11(12):1635-1637.
2. Barbe MT, Reker P, Hamacher S, et al. DBS of the PSA and the VIM in essential tremor: a randomized, double-blind, crossover trial. Neurology. 2018;91(6).
3. Fukushima K, Hashimoto T, Yako T, et al. Deep brain stimulation on neuronal intranuclear inclusion disease–related tremor: a double‐edged impact? Mov Disord Clin Pract. 2022;9(7):983-986.
4. Shepherd H, Heartshorne R, Osman-Farah J, Macerollo A. Dual target deep brain stimulation for complex essential and dystonic tremor – a 5-year follow up. J Neurol Sci. 2024;457:122887.
5. Limousin P, Speelman JD, Gielen F, Janssens M, Collaborators S. Multicentre european study of thalamic stimulation in parkinsonian and essential tremor. J Neurol Neurosurg Psychiatry. 1999;66(3):289-296.

« Back to 2026 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/efficacy-of-bilateral-ventral-intermediate-nucleus-deep-brain-stimulation-in-patients-with-neuronal-intranuclear-inclusion-disease-related-tremor-a-longitudinal-case-series/