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Background Palatal tremor (PT) is an uncommon movement disorder that may be classified into symptomatic (SPT) or essential (EPT). The etiology of SPT is varied, with involvement of the Guillain‐Mollaret triangle (GMT) and inferior olivary hypertrophy. EPT is associated with ear clicks and normal imaging and may have a functional basis. Objectives This study aims to explore the clinical and radiological features of a large cohort of patients with PT. Methods This is a retrospective chart review of patients with PT who were evaluated by the movement disorders subspeciality of the neurology department. Demographic, clinical, and imaging details of patients with PT were documented. Results A total of 22 patients with PT comprising 17 with SPT and 5 with EPT were included in this study. No patient was aware of the PT. Ear clicks were reported in 2 patients with SPT and in 3 patients with EPT. The most common etiology for SPT was vascular, followed by degenerative conditions. Patients with SPT had associated features such as tremor (70.6%), ataxia (64.7%), dystonia (52.9%), myoclonus (17.6%), and eye movement abnormalities (75%). Lesions involving the GMT were found in 82% of patients with SPT. Apart from PT, patients with EPT had no other motor symptoms, and imaging was normal. Of the patients with EPT, 2 had additional functional movement disorders. Conclusion PT has significant etiological heterogeneity and can be easily missed because of the lack of awareness by patients. Involvement of the inferior olivary nucleus may not be necessarily observed. A functional etiology should be considered in cases of EPT.

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Objective The novel coronavirus disease (COVID-19) pandemic and public health measures to control it have resulted in unique challenges in the management of patients with deep brain stimulation (DBS). We report our experience with the management of acute worsening of symptoms due to battery exhaustion in 3 patients with DBS. Methods Patients with DBS for movement disorders who visited the emergency room due to battery exhaustion during the nationwide lockdown from April to May 2020 were included. Results Two patients with subthalamic nucleus-DBS for Parkinson’s disease (PD) and one with globus pallidus interna-DBS for generalized dystonia presented with acute worsening of symptoms due to battery exhaustion. Urgent battery replacement was performed in both patients with PD. The patient with generalized dystonia was managed with medication adjustment as he chose to defer battery replacement. Conclusion DBS battery replacement can be an emergency. Decisions regarding DBS battery replacement should be individualized during this COVID-19 pandemic.

Sialidosis is an inborn error of metabolism due to a defect in the NEU1 gene and manifests as two phenotypes: mild type I and severe type II. The cherry red spot (CRS) is a characteristic feature in both types of sialidosis; reports of sialidosis without a CRS are rare. We report two cases of genetically confirmed sialidosis type I with a typical presentation of progressive cortical myoclonus and ataxia but without the CRS. A previously reported homozygous pathogenic variant p.Arg294Cys was detected in the first case, and a novel homozygous pathogenic variant p.Arg305Pro was detected in the second case. Additionally, we reviewed the literature describing cases with similar mutations to find a genetic basis for the absence of a CRS. Milder mutation of both alleles detected in both patients may be the reason for the absence of a CRS.