Magnetic resonance imaging of hypertrophic olivary degeneration

Hypertrophic Olivary Degeneration Following Listerial Rhombencephalitis

“…A lesion on the afferent dentato-rubro-olivary fibers result in unilateral or bilateral HOD, depending on its location along the pathway. [1][2][3] In the case reported here, however, accurate identification of the primary focus of HOD was difficult because lesions appeared throughout the brain stem.…”

“…Disruption of the GMT results in a varied clinical presentation, including palatal tremor, dentatorubral tremor (Holmes tremor), and ocular myoclonus. [1][2][3][4] Although this patient underwent an otolaryngologic examination for globus pharyngeus and an altered voice, it was difficult to diagnose HOD. Delayed neuronal degeneration, such as HOD, may be diagnosed in patients who have been treated for rhombencephalitis that displays only vague symptoms, such as the sensation of a foreign body in the neck.…”

“…1,2 Listerial rhombencephalitis is a rare etiology of HOD. [1][2][3][4] We report the case of a patient with delayedonset HOD following listerial rhombencephalitis.…”

“…5,7,8 Hypertrophic olivary degeneration is a form of trans-synaptic degeneration caused by disruption of the DROP, also known as the Guillain-Mollaret triangle (GMT), connecting the ipsilateral inferior olivary nucleus, the dentate nucleus of the contralateral cerebellum, and the ipsilateral red nucleus. [1][2][3] The epidemiology and etiology of HOD are not fully understood. The most common causes of injury to the GMT are intraparenchymal hemorrhage, arteriovenous malformation, an infarcted tumor, surgery, and multiple sclerosis, [1][2][3] but HOD following listerial rhombencephalitis is very rarely reported.…”

“…[1][2][3] The epidemiology and etiology of HOD are not fully understood. The most common causes of injury to the GMT are intraparenchymal hemorrhage, arteriovenous malformation, an infarcted tumor, surgery, and multiple sclerosis, [1][2][3] but HOD following listerial rhombencephalitis is very rarely reported. 4 The proposed mechanism of HOD is that is an atypical form of trans-synaptic degeneration thought to be due to the loss of synaptic, afferent input to the inferior olivary nucleus, resulting in hypertrophy, initially of the affected neurons, followed by subsequent atrophy.…”