Spasticity complicating metrizamide myelography.

Temporary but considerable increase in spasticity following myelography using metrizamide at 300 mgs I/ml concentration occurred in 4 patients. In 3 of the patients the diagnosis is uncertain, but it is likely to be some form of degenerative disease involving motor pathways in two of them; the fourth case has cervical spondylotic myelopathy. The spasticity might be related to the anticholinesterase activity of metrizamide or to competitive inhibition of endogenous glucose metabolism by the deoxyglucose component of the metrizamide molecule.

Ocular palsy preceding chronic relapsing polyneuropathy by several weeks.

Three patients exhibited an unusual variant of chronic relapsing polyneuritis in which extraocular muscle palsies developed 19 days, 20 days, and 3 1/2 months, respectively, before the neuropathy affected the limbs. The peripheral neuropathy evolved over 7 to 12 weeks, lasted 15 months to 13 years, and relapsed in every case. Each patient had dysphagia, areflexia, sensory loss, and weakness of all four limbs, which in two was asymmetrical. Slowed motor nerve conduction and prolonged F wave latencies were present, and the cerebrospinal fluid protein level was elevated without increased cell count. No patient recovered fully despite treatment with immunosuppressant drugs.

Familial paroxysmal dystonia induced by exercise.

A mother and daughter are described with paroxysmal dystonia induced by exercise. As has been reported in one previous family, the attacks were provoked in the lower limbs by prolonged exertion but not by sudden movements. It was also found that involuntary movements could be induced focally in any limb either by local exercise or by sensory stimulation restricted to that limb.

The role of two-dimensional echocardiography in the detection of potentially embolic intracardiac masses in patients with cerebral ischaemia.

The M-mode and two dimensional echocardiographic data of 62 consecutive cardiac patients referred from neurology centres were analysed retrospectively to establish the use of these techniques in detecting underlying cardiac pathology. All patients had presented initially to a neurologist with transient or permanent focal cerebral or retinal ischaemia, and had been referred for cardiac assessment after neurological investigations failed to establish the underlying cause of the neurological event. Patients were divided into two groups. In 30 patients the referring neurologist had found no evidence of cardiac disease (Group I); in the other 32 patients either heart disease or an arrhythmia had been diagnosed prior to cardiac referral (Group II). One of the patients in Group I had echocardiographic evidence of mitral valve prolapse not detected by the neurologist prior to referral; no cardiac pathology was recognised in the other 29 patients in this group. In seven of the 32 (22%) patients from Group II, a cardiac mass presumed responsible for the neurological manifestations was demonstrated echocardiographically, and in six of these histological confirmation was obtained following surgery or at necropsy. Two dimensional echocardiography was the only investigation which visualised the intracardiac pathology in four patients. In the remaining three patients, valve vegetations (two cases) and an atrial tumour (one case) were demonstrated by both echocardiographic methods. In patients with either clinical evidence of cardiac disease or an arrhythmia who have experienced one or more episodes of cerebral or retinal ischaemia, the presence of an intracardiac mass is not uncommon. Two dimensional echocardiography was the method of choice for detecting cardiac thrombus but the use of both methods of ultrasound should be considered as complementary techniques in the investigation of these cases. Routine echocardiography is unlikely to be of value in screening patients who have had a cerebrovascular event and who do not have clinical evidence of heart disease or an arrhythmia.

Niacin depletion in Parkinsonian patients treated with L-dopa, benserazide and carbidopa.

1. Benserazide and carbidopa, decarboxylase inhibitors used in the treatment of Parkinson's disease, have been shown to inhibit the enzyme kynurenine hydrolase in rat and mouse liver. This results in reduced synthesis of nicotinamide coenzymes from tryptophan, and hence an increased reliance on dietary niacin. 2. Pellagra might be expected as a result of this inhibition of endogenous synthesis of nicotinamide nucleotides, but has not been reported in patients treated with either drug. 3. The urinary excretion of N1-methyl-nicotinamide, a product of nicotinamide nucleotide metabolism, is considerably reduced in patients treated with dopa alone or in combination with an inhibitor of peripheral dopa decarboxylase, to as low as 40% of the control value. This means that many of these patients could be classified as 'at risk' of niacin deficiency, even if not frankly deficient. 4. Patients treated with dopa plus a decarboxylase inhibitor, but not those treated with dopa alone, also show a reduced excretion of xanthurenic acid, and an increased excretion of kynurenine, as would be expected after inhibition of the kynurenine pathway, and possibly indicative of marginal vitamin B6 deficiency.

Factors influencing the risk of multiple sclerosis developing in patients with optic neuritis.

One-hundred and forty-six patients who had presented with optic neuritis but without evidence of demyelination elsewhere in the nervous system, and in whom no specific cause could be identified, were reassessed clinically between one month and twenty-three years after the onset. Fifty-eight patients (40 per cent) had developed MS. All 146 patients were HLA-typed. Three factors were identified which were significantly associated with the development of MS: positive typing for the HLA antigen BT 101, winter onset of the initial attack of optic neuritis in BT 101-positive patients only, and recurrent attacks of optic neuritis. The application of these results to the individual patient is of limited use. However, recurrent attacks of optic neuritis should be given the same significance in the clinical classification of MS as episodes of demyelination occurring elsewhere in the central nervous system in a patient with a previous attack of optic neuritis. The results suggest that optic neuritis is caused by two different environmental agents or groups of agents and that the agent which is most common in the winter leads to the development of MS in the genetically susceptible individual. The agent more common in the summer is much less likely to cause MS in either suscetible or non-susceptible individuals. The biological role of the HLA system in the handling of foreign antigens is discussed and it is suggested that the presence of the HLA antigens associated with MS confers a specific disadvantage on individuals in the ability to handle infection by the MS causative agent and that this allows damaging immunological processes to develop.

Gold encephalopathy.

Encephalopathy is described developing in a 42 year old man who was receiving gold treatment for rheumatoid arthritis.

Flaccid paraplegia: a feature of spinal cord lesions in Holmes-Adie syndrome and tabes dorsalis.

In a patient with Holmes-Adie syndrome, and in another with tabes dorsalis, a transverse cord lesion resulted in a severe, but flaccid paraplegia with absent tendon reflexes. Flexor spasms were severe in both patients, but spasticity was absent. The significance of these observations is discussed in relation to the functional and anatomical disorder in these two syndromes.

Tolosa-Hunt syndrome. The dangers of an eponym.

Two cases of painful ophthalmoplegia are described which were initially thought to be examples of the Tolosa-Hunt syndrome. Both were partially responsive to steroid treatment. Subsequent investigations showed that in one case the condition was due to an aneurysm and in the other to a malignant lymphoma.