Clinical and Imaging Profile of Patients with Palatal Tremor

Abstract

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.

Tremor Syndromes: An Updated Review

“…However, the term myoclonus may still apply since the movement is produced by contractions of only agonist muscles (either tensor veli palatine or levator veli palatine), rather than alternating, oscillatory antagonist contractions which produce typical oscillatory movement characterizing tremor. Furthermore, in contrast to typical tremor, this focal movement disorder often has a jerky and arhythmic component, particularly when present as a functional (psychogenic) movement disorder ( 67 , 68 ).…”

“…In addition to functional (psychogenic) palatal tremor ( 71 ), there are many other etiologies. Previous case series have documented vascular abnormalities (posterior circulation strokes, aneurysms, arterio-venous malformation), genetic abnormalities (polymerase gamma-related mitochondrial disease, SCA type 20, Alexander disease), and traumatic brain injury as the commonest etiologies of SPT ( 67 , 72 ). In addition, there are reports of an array of neurodegenerative (progressive ataxia with palatal tremor), infectious (Whipple disease, tuberculosis, toxoplasmosis), inflammatory/demyelinating (neurosarcoidosis, multiple sclerosis, Behcet's disease) and neoplastic conditions (posterior fossa tumors) associated with SPT ( 67 , 72 , 73 ).…”

“…Previous case series have documented vascular abnormalities (posterior circulation strokes, aneurysms, arterio-venous malformation), genetic abnormalities (polymerase gamma-related mitochondrial disease, SCA type 20, Alexander disease), and traumatic brain injury as the commonest etiologies of SPT ( 67 , 72 ). In addition, there are reports of an array of neurodegenerative (progressive ataxia with palatal tremor), infectious (Whipple disease, tuberculosis, toxoplasmosis), inflammatory/demyelinating (neurosarcoidosis, multiple sclerosis, Behcet's disease) and neoplastic conditions (posterior fossa tumors) associated with SPT ( 67 , 72 , 73 ). Although not universal, MRI of the brain often reveals hypertrophic degeneration of the olive and other focal lesions in the Guillain-Mollaret triangle (formed by the ipsilateral red nucleus, inferior olivary nucleus, and contralateral dentate nucleus).…”

Palato‐Pharyngo‐Laryngeal Myoclonus with Facial Involvement After an Ischemic Stroke

“…Palatal myoclonus, also described as palatal tremor, is characterized by rhythmic continuous 0.5 to 5 Hz movements of the soft palate and pharynx. 1 There are two categories described: symptomatic palatal tremor, because of a brainstem or cerebellar lesion, and essential palatal tremor, with no associated structural lesion. 2,3 Palatal myoclonus can rarely be associated with synchronous myoclonus of other branchial arch muscles, the diaphragm, facial muscles, or even the extremities.…”

“…Although symptomatic palatal tremor affects the levator veli palatini, it can also rarely cause subjective auditory phenomena, likely because of some fibers inserting on the eustachian tube. 1,5 The patient's mild improvement in symptoms with the combination of baclofen and carbamazepine suggest a potential therapeutic option that warrants further investigation.…”