A case of Holmes tremor in which ¹²³I-IMP SPECT and MRI findings suggest damage to the cerebellothalamic tract and the dentato-rubro-olivary pathway

Abstract

A 75-year-old woman was referred to our department in October 2022 with ataxia and involuntary movements of the right upper and lower limbs. She had experienced a left pontine hemorrhage in March 2021, which was managed conservatively. However, she had residual right-sided hemiplegia. In addition, she had cerebellar ataxia and a 2 ‍Hz resting tremor of the right upper and lower limbs, which was enhanced while maintaining posture and contemplation. Based on her history, and the findings of MRI and nuclear medicine imaging, we diagnosed the patient with Holmes tremor due to pontine hemorrhage. Holmes tremor is a rare movement disorder secondary to brainstem and thalamic lesions, characterized by a unilateral low-frequency tremor. In this case, ¹²³I-IMP SPECT and MRI shows damage to the cerebellothalamic tract and dentaro-rubro-olivary pathway.