OBJECTIVE Hashimoto encephalopathy (HE) is known as a steroid- responsive encephalopathy associated with autoimmune thyroiditis or nonvascular inflammation-related autoimmune meningoencephalitis. The average age of onset of HE is approximately 50 years; and it is more common in women. The onset of HE may be acute or subacute. The course of most HE cases is relapsing and remitting, which is simi...

Although it is a very rare situation, four-rooted maxillary second molars can occur. The existence of two palatal roots is extremely rare and ranges about only 0.4%. The aim of this study is to present and document a very rare anatomic configuration of a four-rooted maxillary second molar. Anatomic variation in the number of roots and root canals can occur in any tooth, although some cases can ...

Delayed-onset continuous bruxism due to brain stem infarction has not yet been reported. A 49-year old man presented with quadriplegia and ophthalmoplegia. Brain MRI showed acute infarction in the bilateral midbrain, right thalamus and the superior cerebellum. One month later, the patient developed bruxism which persisted during sleep. A palatal myoclonus was not observed. Follow up MRI taken 4...

Hypertrophic olivary degeneration (HOD) is secondary degeneration of the inferior olivary nucleus (ION) due to a primary lesion in the dento-rubro-olivary pathway. This pathway is known as the Guillain and Mollert triangle, containing the dentate nucleus and the contralateral red and inferior olivary nuclei (figure e-1 on the Neurology® Web site at www.neurology.org). The commonest presenting s...

Three siblings presented with a progressive neurological disorder beginning in the third decade of life and characterised by palatal myoclonus, nystagmus, bulbar weakness and spastic tetraparesis. There was no evidence of intellectual deterioration or seizures. CT scan showed marked brainstem atrophy in two patients and basal ganglia calcification in one. MRI scan in one showed high signal in t...

Primary lesion of the dentatorubral-olivary pathway may lead to secondary degeneration of the inferior olivary nucleus (ION), resulting in a rare but clinically relevant condition called hypertrophic olivary degeneration (HOD). Patients with HOD often present with palatal myoclonus, ataxia, tremor, dysarthria and/or hemiparesis. Early MRI shows T2 lengthening in the dentate nucleus, superior ce...

A 28-year-old woman presented with hemi-dystonic movements on the left. Four years earlier, a ruptured vascular malformation caused a hemorrhagic stroke on the left cerebellar hemisphere (Figure 1B), evacuated by surgery. MRI revealed right hypertrophic olivary degeneration (HOD) (Figure 1A) and reduction of cerebellar-rubro pathways (Figure 2). HOD is a trans-synaptic degeneration affecting th...