Spontaneous disappearance of Holmes' tremor in a patient with a midbrain cavernous hemangioma.

Abstract

Holmes’ tremor is an uncommon movement disorder characterized by a combination of resting, postural and kinetic tremors, and is difficult to treat. We observed a spontaneous disappearance of Holmes’ tremor caused by a midbrain cavernous hemangioma, along with detailed serial neuroimaging studies. A 54-year-old right-handed man presented to our clinic complaining of the gradual onset of a left arm tremor that prevented him from holding a cup or using a spoon during a meal. He had no personal or family history of head trauma. Upon examination, the patient had a 4to 5-Hz resting tremor and severe postural and kinetic tremors in his left arm. His muscle power and deep tendon reflex were normal, but a sensory examination revealed that light touch, pinprick, and vibratory sensations were diminished on his left face, extremities, and body. Although the patient exhibited partial right third cranial nerve palsy with preservation of the pupil reflex and adduction palsy of the right eye, his other cranial nerves were intact. Magnetic resonance imaging (MRI) revealed an ovalshaped mass lesion on his right midbrain tectum (Fig. 1a–d). The upper border of the lesion extended to the lower aspect of the right thalamus, and the lower border extended to the upper aspect of the right pons. There were multiple hyperintense centers surrounded by hypointense rims and fluid–fluid levels without perifocal edema; however, contrast MRI with gadolinium did not reveal any enhancement. These findings are compatible with cavernous hemangioma. The patient declined the performance of any surgical interventions, including stereotactic thalamotomy, and pharmacological treatment such as levodopa, anticholinergics, and propranolol were unsuccessful. Two months later, the patient reported that his tremor had unexpectedly improved markedly. Upon examination, his postural and intentional tremors had disappeared, but a mild resting tremor of the left hand and subtle left arm weakness were observed; the patient was satisfied with his condition without any medication. Repeated brain MRI (Fig. 1e–h) revealed that the previous lesion had primarily manifested due to a recurrent hemorrhage, which exerted a mass effect on the right crus cerebri (Fig. 1e, f). Superiorly, there was displacement and compression of the right thalamus with signs of perilesional edema (Fig. 1g, h). There have been several reports of the spontaneous disappearance of a tremor after ischemic stroke, and most of these cases were related to essential and resting tremors [1, 2]. In the present case, the patient’s postural and kinetic tremors disappeared as the cavernous hemangioma grew larger with thalamic involvement. However, Holmes’ tremor can occur secondarily to thalamic lesions, such as an abscess or thalamomesencephalic cavernoma [3, 4]. This seemingly contradictory finding can be explained by different patterns of thalamic involvement. Although studies have suggested that Holmes’ tremor results from disruption of the cerebello-thalamo-cortical pathway, thalamotomy and deep brain stimulation of the ventral intermediated nucleus (VIM) of the thalamus can ameliorate midbrain tremors [5]; In our case, it seems that the thalamic lesion was located close to the target of stereotaxic surgery, i.e., & Jung Han Yoon jhyoon@gmail.com