No abstract

The authors describe two patients suffering from demyelinating central nervous system disease who developed intense vertigo and downbeat nystagmus upon tilting their heads relative to gravity. Brain MRI revealed in both cases a single, small active lesion in the right brachium conjunctivum. The disruption of otolithic signals carried in brachium conjunctivum fibres connecting the fastigial nucleus with the vestibular nuclei is thought to be causatively involved, in agreement with a recently formulated model simulating central positional nystagmus. Insufficient otolithic information results in erroneous adjustment of the Listing's plane in off-vertical head positions, thus producing nystagmic eye movements.

Axonal degeneration and brain tissue loss occur during disease progression in multiple sclerosis (MS) and are expected to influence neurotransmitter activities, with consequences on neurologic and psychiatric symptomatology. We searched for relationships of disease duration, disability, and severity of MS patients to CSF levels of the major metabolites of noradrenaline, dopamine, and serotonin, MHPG, methoxyhydroxyphenylglycol (MHPG), homovanillic acid, and 5-hydroxyindoleacetic acid (5-HIAA), respectively, in 39 patients with relapsing-remitting (RR) MS in remission, and 26 patients with progressive (PR) MS. Disability and Disease Severity were assessed by the Expanded Disability Status Scale (EDSS) and the Multiple Sclerosis Severity Score (MSSS). Compared with the levels of 50 control subjects, MHPG levels were not different in either MS group, correlated negatively to duration of illness and number of relapses in the RRMS group, but not to EDSS score or to MSSS.Homovanillic acid levels were significantly lower only in the PRMS group, with a negative correlation to duration of illness, and a strong negative correlation to EDSS score, but not to MSSS. 5-HIAA was significantly lower in both RRMS and PRMS groups. In the RRMS group, 5-HIAA levels were negatively related to EDSS and to MSSS. Multiple regression analyses revealed a significant association of MHPG to duration of illness, and a strong negative association of 5-HIAA to MSSS rather than to EDSS. The strong negative correlation of MSSS to CSF 5-HIAA levels in RRMS group of patients indicates that deficits in central serotonergic activity are related to the rate of disability accumulation in RRMS, and could be linked to the reported reduction of disease activity by serotonergic drugs.

Occipital neuralgia has been attributed to lesions at a peripheral nerve or radicular level. On rare occasions, it has been associated with cervical cord lesions. We report a 55-year-old woman who presented with an isolated occipital neuralgia and was found on further investigation to have a restricted, isolated myelitis at C2 level. This represents the second reported case of occipital neuralgia due to C2 myelitis and should alert clinicians to considering cervical MRI in patients with occipital neuralgia.