Holmes' Tremor with Shoulder Pain Treated by Deep Brain Stimulation of Unilateral Ventral Intermediate Thalamic Nucleus and Globus Pallidus Internus

A 21-year-old male was admitted with severe right arm and hand tremors after a thalamic hemorrhage caused by a traffic accident. He was also suffering from agonizing pain in his right shoulder that manifested after the tremor. Neurologic examination revealed a disabling, severe, and irregular kinetic and postural tremor in the right arm during target-directed movements. There was also an irregular ipsilateral rest tremor and dystonic movements in the distal part of the right arm. The amplitude was moderate at rest and extremely high during kinetic and intentional movements. The patient underwent left globus pallidum internus and ventral intermediate thalamic nucleus deep brain stimulation. The patient improved by more than 80% as rated by the Fahn-Tolosa-Marin Tremor Rating Scale and Visual Analog Scale six months after surgery.

Outcome of Gamma Knife Thalamotomy in Patients with an Intractable Tremor

OBJECTIVE: Tremor is a common movement disorder that interferes with daily living. Since the medication for tremor has some limitations, surgical intervention is needed in many patients. In certain patients who cannot undergo aggressive surgical intervention, Gamma Knife thalamotomy (GKT) is a safe and effective alternative. METHODS: From June 2012 to August 2013, 7 patients with an intractable tremor underwent GKT. Four of these 7 patients had medical comorbidities, and 3 patients refused to undergo traditional surgery. Each patient was evaluated with the modified Fahn-Tolosa-Marin tremor rating scale (TRS) along with analysis of handwriting samples. All of the patients underwent GKT with a maximal dose of 130 Gy to the left ventralis intermedius (VIM) nucleus of the thalamus. Follow-up brain MRI was performed after 3 to 8 months of GKT, and evaluation with the TRS was also performed. RESULTS: Six patients showed objective improvement in the TRS score. Excluding one patient who demonstrated tremor progression, there was 28.9% improvement in the TRS score. However, five patients showed subjective improvement in their symptoms. On comparing the TRS scores between follow-up periods of more and less than 4 months, the follow-up TRS score at more than 4 months of GKT was significantly improved compared to that at less than 4 months of GKT. Follow-up MRI showed radiosurgical changes in 5 patients. CONCLUSION: GKT with a maximal dose of 130 Gy to the VIM is a safe procedure that can replace other surgical procedures.

The electrophysiological characteristics of ventralis intermedius nucleus and its role in localizations of Vim-thalamotomy for Parkinson's disease patients / 解放军医学杂志

Objective To investigate the electrophysiological characteristics of the ventralis intermedius nucleus (Vim) in order to find an easy and safe way to confirm the target in Vim-thalamotomy. Method In microelectrode-guided selective Vim-thalamotomy for 23 Parkinson's disease patients, the background activity, amplitude and discharge frequencies of Vim were compared with its surrounding structures. The response of kinesthetic neuron and tremor cell to microstimulation was also compared. Result There were differences in backgroud activity and discharge amplitude for Vim, ventralis lateralis nucleus (VL), ventralis caudalis nucleus (VC), and internal capsule. Based on the response to active or passive movement of contralateral limb tremor cells were divided into two subgroups, which were different in localization. Contralateral tremor showed different response when the two subgroups of tremor cells were mircrostimulated. Conclusion The anterior border of Vim was easily found by microrecording. Only by combining microstimulation with microrecording could the posterior border of Vim and its interior and lateral ordination of target were identified exactly and safely. Kinesthetic neurons and tremor cells which responded to the movement of contralateral limbs should be destroyed.