The central nervous system in motor neurone disease

Retrograde transneuronal transfer of the C-fragment of tetanus toxin

The transport of the C-fragment of tetanus toxin after intramuscular injection was studied with immunohistochemical techniques. Brainstems and spinal cords of mice were examined after injections of C-fragment into the tongue or forearm. Labelled motorneurons were observed within 6 h. By two days after injection, the bulk of detectable C-fragment had passed out of motorneurons into the surrounding neuropil. C-fragment, like native tetanus toxin, appears to be transferred from motorneurons to presynaptic structures to an extent not observed with other proteins. It is useful in the study of retrograde transneuronal transfer since it lacks the toxicity of tetanus toxin.

Central motor conduction is abnormal in motor neuron disease

Conduction in the central motor pathways of the brain and spinal cord was studied in 12 patients with motor neuron disease. Six healthy volunteers served as controls. Transcutaneous electrical stimulation of the cortex, cervical cord, thoracic cord and conus medullaris was used to determine motor latencies to the biceps brachii, thenar eminence and tibialis anterior muscles. Prominent, and often asymmetrical, slowing of central motor conduction was demonstrated in seven of the 12 patients; these findings were most marked in the spinal cord and in most cases correlated with clinical features of corticospinal involvement. In general it was more difficult to excite motor pathways in the central nervous system in the patients with motor neuron disease than in control subjects. Evidence of subclinical involvement of central motor pathways was found in five patients. The central lesion in motor neuron disease may thus contribute more significantly to the clinical deficit than has been realised, since the clinical signs of the upper motor neuron lesion are often masked by the more obvious lower motor neuron features.

Motor neurone disease in the Lothian Region of Scotland 1961-81

One hundred and sixty one patients with motor neurone disease (MND), from the Lothian Region of Scotland, were studied in an attempt to identify factors important in disease aetiology. Onset of the disease was between 1961 and 1981 and the incidence was highest between 1968 and 1975. The probability of developing MND was greatest between the ages of 65 and 69, and a greater proportion of female patients than of males had onset in the bulbar muscles. Some 5% of patients had a positive family history of MND. There was no evidence that infective agents were important in the aetiology of the disease. There was a suggestion that the patient group contained a greater number of electrical workers, food, drink and tobacco workers, and rubber workers than would have been expected. However, a larger series of patients would be needed to confirm an increased susceptibility to MND in individuals engaged in these occupations.

An unusual form of motor neuron disease following a cat bite

A case of motor neuron disease with clinical and pathological resemblance to amyotrophic lateral sclerosis (ALS) in a woman who was severely bitten on the ankle by a cat is described. Weakness first appeared at the ankles and relentlessly advanced proximally, terminating in death from pulmonary failure in a year. A number of unusual features that are uncharacteristic of ALS were found that included a markedly elevated antinuclear antibody titre in the serum and the presence of prominent oligoclonal bands in the cerebrospinal fluid. The spinal cord showed loss of anterior horn cells and pyramidal degeneration that are characteristic of ALS, but an extraordinary finding was the presence of transmural granulomatous inflammation of numerous small and medium sized vessels, especially veins, in the subarachnoid space around the cord. There were also inflammatory changes in the brainstem and spinal cord consisting of microglial and astrocytic nodules and perivenous cuffing by mononuclear cells. Ill-defined hyaline eosinophilic cytoplasmic inclusions were seen in some remaining anterior horn cells. No viral particles were found by electron microscopy despite an extensive search. Virological studies were inconclusive but there is reason to believe that this patient's illness was caused by an as yet unidentified virus.

Motor and psychomotor functions in amyotrophic lateral sclerosis evaluated by tests of motor ability

18 patients with typical sporadic Amyotrophic Lateral Sclerosis (ALS) were investigated by the Motor Accuracy and Speed Test (MAST) and 18 healthy age- and-sex-matched volunteers, acted as controls. All performed each of the five tests 10 times with both the right and the left hands and repeated the experiment after one week by the same procedure. Motor performances were better in the controls than in the ALS patients only in the first three tasks. At retest, one week later, the controls generally improved while ALS patients did not. The mean percentages of changes showed a statistically significant difference in the fifth task. Analysis of the results suggests the possibility that, among the other mechanisms, a disturbance of motor learning ability could be operating in ALS patients.

Degeneration of Betz cells in motor neuron disease. A Golgi study

A morphological study using a modified Golgi impregnation technique was carried out on Betz cells in the motor area of eight patients with motor neuron disease (MND) and age-matched controls without abnormal neuropathological findings during routine examination. Betz cells were categorized as normal (type I), or those with moderate (type II) or marked (type III) degeneration of dendrites. Types II and III Betz cells tended to be dominant in the cases of MND, whereas type I Betz cells constituted the highest percentage in most of the control cases. The frequently observed morphological alterations of Betz cells in MND were accumulation of lipofuscin, degeneration or loss of dendrites, and reactive astrocytic gliosis around the Betz cell soma. It was suggested that Betz cell changes in MND are not only due to aging but also to evident pathological processes, since the above-mentioned findings were more extensive in the MND cases than in the control cases. Also, the so-called lower motor neuron disease belongs to one basic disease termed "motor neuron disease", because the pathological changes of Betz cells were observed even in cases of spinal progressive muscular atrophy alone or associated with progressive bulbar palsy, which are devoid of pyramidal tract degeneration and signs of upper motor neuron lesion.

A quantitative study of intermediolateral column cells in motor neuron disease and the Shy-Drager syndrome

The intermediolateral column neurons in the lateral horns of the grey matter of the thoracic spinal cord were counted in five patients who had died of motor neuron disease, two of the Shy-Drager syndrome and three of other neurological diseases not affecting the spinal cord or roots. The number of intermediolateral column cells in all the motor neuron disease cases was slightly reduced compared with the control cords, this difference being apparent both when the whole thoracic sympathetic outflow was assessed as well as its upper, middle and lower thirds. The difference, however, was not statistically significant. By contrast, in Shy-Drager cases there was a highly significant reduction in intermediolateral column cells compared with the normal cords.

A survival analysis of 155 cases of progressive muscular atrophy

We performed a survival analysis of 155 cases of progressive muscular atrophy (PMA). In about half the cases, hands were involved first, the lower limbs in 30% and the shoulder girdle in 23%. The lifetables of PMA, adjusted to the expected mortality, showed a survival rate of 61.3% and 56.4% at three and five years, respectively. The location of onset symptoms did not modify the life expectancy, whereas the age of the patients at the moment of first diagnosis had a great influence on the course of the disease. The patients were further subdivided in two groups on the basis of the diffusion of the neuromuscular damage at the moment of the diagnosis. The course of the patients with a localized disease was markedly better than that of subjects with widespread disease. Some hypotheses are made about the latter group of cases.

Somatosensory evoked potentials in motor neuron disease

We studied median somatosensory evoked potentials (SEPs) in an unselected series of 30 patients with sporadic motor neuron disease (MND). SEPs were affected in 17 patients (57%), with a higher incidence of abnormality in amyotrophic lateral sclerosis and bulbar palsy than in progressive muscular atrophy. In a majority of patients, simultaneous bilateral stimulation of the median nerve revealed a delay or absence of scalp-recorded central N32 and/or N60, leaving the earlier peaks intact. In the remaining cases, the N19 peak was asymmetrically prolonged. These findings suggest common involvement of somatosensory pathways in MND, either at cortical or subcortical levels, and correlate with neuropathologic reports of neuronal degeneration beyond the primary motor system.

Sensory involvement in motor neuron disease: further evidence from automated thermal threshold determination

Thermal thresholds were determined in 40 patients with motor neuron disease and in 40 age- and sex-matched healthy subjects. The thermal thresholds were estimated on the skin of wrist and ankle using an automated microprocessor controlled system and the "two alternative forced-choice method" of psycholphysical analysis. Abnormalities of thermal thresholds (greater than or equal to 99th percentile) were seen in 80% of the motor neuron disease patients. The results are in agreement with reports of sensory pathway involvement in the literature. Thermal threshold abnormalities are common in motor neuron disease and indicate the involvement of the small fibre afferent pathways.

Amyotrophic lateral sclerosis: Part 1. Clinical features, pathology, and ethical issues in management

Amyotrophic lateral sclerosis (ALS) is a progressive degenerative disease of the motor system in adults that occurs in sporadic, familial, and Western Pacific forms. Involvement of non-motor pathways has been increasingly recognized, both clinically and pathologically. Although the usual course is relentlessly progressive with death in half the cases within three years from onset, it can sometimes be protracted. Degeneration and loss of large motor neurons in the cerebral cortex, brainstem, and cervical and lumbar spinal cord are characteristic. Marked reduction in the number of large myelinated fibers is notable in the cervical and lumbar ventral roots. Peripheral nerves show reduced numbers of large myelinated fibers, acute axonal degeneration at all levels, and distal axonal atrophy. Motor end-plates reveal small or absent nerve terminals. Subclinical non-motor system involvement includes neuronal loss in Clarke's nucleus and dorsal root ganglia, degeneration of non-motor tracts in the spinal cord, loss of receptors in the dorsal horns of the spinal cord, and myelinated fiber loss with segmental demyelination in sensory and mixed nerves. The serious implications of the diagnosis of ALS make it mandatory to exclude similar potentially treatable disorders. Management should be multidisciplinary, and discussions with the patient and family members should be frank and frequent. Discussions about ventilatory support should take place early in the disease so that death from respiratory failure can be prevented, when that is desired, and conversely to obviate the discontent and anger that accompany involuntary life on a ventilator.

Pain in motor neuron disease

Twenty-seven of 42 patients with motor neuron disease had significant pain. The nature and duration of the pain are described along with an illustrative case-report. The aetiology and most effective treatment of this common complication of motor neuron disease remain unclear.

Ganglioside patterns in amyotrophic lateral sclerosis brain regions

In a search for evidence of biochemical disorders in regions of postmortem brain other than the motor cortex in amyotrophic lateral sclerosis (ALS), ganglioside patterns were also examined in the frontal, temporal, and parahippocampal gyrus cortex. In 21 ALS brains studied (20 sporadic, 1 familial), abnormal patterns were found in the frontal cortex (81%), temporal cortex (75%), motor cortex (70%), and parahippocampal gyrus cortex (71%). Patterns were established by measuring the percentage distribution of 12 ganglioside species. Two abnormal patterns were detected. One was based on low proportions of GD1b, GT1b, and GQ1b associated with high proportions of GM2 and GD3 (GM1, GD1a, GD2, and GT1a values were normal). The second abnormality was the appearance of Gx. Neither abnormality was seen in the 13 non-ALS control brains. The first, and predominant, abnormality was found in the frontal cortex in 14 brains, and the second was observed in 13 brains; 10 brains showed both abnormalities. These findings thus constitute evidence that the disease process in ALS extends beyond the motor cortex and involves neurons in several brain areas.

Cognitive impairment in motor neuron disease

A systematic investigation of the cognitive functions of 22 patients affected with motor neuron disease (MND) compared to 36 controls matched for age and education was performed. The MND group showed cognitive performances slightly but significantly lower than the control group; 6 MND patients, however, had decidedly pathological values. Cognitive impairment was stereotyped and global, with sparing of memory. There was no significant difference between patients with isolated involvement of the lower motor neuron and those with associated pyramidal involvement. Our neuropsychological findings are in agreement with previous clinical, neuroradiological and pathological reports indicating extra-motor cerebral involvement in MND.

Primary lateral sclerosis; a debated entity

Two patients suffering from slowly progressing spastic paraparesis are presented. Both of them underwent a several years' follow-up, and extensive laboratory, radiological and neurophysiological investigations in order to rule out known specific causes for pyramidal tract involvement. After these exclusion studies, the diagnosis of primary lateral sclerosis (PLS) was derived. The present cases provide further evidence of the long-debated PLS as a disease entity.

Familial occurrence of amyotrophic lateral sclerosis, parkinsonism, and dementia

We report here on a 59-year-old man from southwest Germany who died after a 14-year course of an illness characterized by progressive dementia, parkinsonism, and amyotrophic lateral sclerosis. Postmortem examination revealed Alzheimer's neurofibrillary tangles in the substantia nigra, innominata, locus ceruleus, parahippocampal gyrus, and less frequently in the hippocampus and the cerebral cortex. Investigation of the patient's pedigree back to the 17th century revealed nine additional family members who had exhibited signs of amyotrophic lateral sclerosis or parkinsonism-dementia or both. The pedigree suggests that a recessive trait with genetic epistasis is responsible for the disorder.

Motor neuron disease in the province of Turin, Italy, 1966-1980. Survival analysis in an unselected population

We performed a population based survival analysis of all incident cases (220) of motor neuron disease (MND) in the province of Turin, Italy, during the period 1966-1980. 175 cases were diagnosed as amyotrophic lateral sclerosis (ALS), 43 as progressive muscular atrophy (PMA) and 2 as progressive bulbar palsy (PBP). The life-tables of MND, adjusted as to the "expected" mortality, showed a survival rate of 27.8% and 22.0% at 5 and 10 years, respectively. The course of PMA and ALS cases was different, with a 5-year survival rate of 66.8% and 17.7%, respectively. Nevertheless both life-tables showed a similar pattern with a rapidly fatal outcome in the first 3 years after diagnosis and a slower death rate in the following years. In each curve, the slopes suggested the presence of 2 subgroups with different prognosis. It is to be stressed that a percentage of PMA patients (25.7%) showed a rapidly fatal outcome and that a subgroup of ALS patients (26.6%) showed a relatively benign course. This might suggest a different individual susceptibility to the disease.

Dementia and motor neuron disease: morphometric, biochemical, and Golgi studies

In three patients dementia without neurofibrillary tangles or Pick bodies antedated amyotrophy by several years. The motor neuron disorder in two patients was characterized by terminal bulbar symptoms; in one it was similar to classic amyotrophic lateral sclerosis. In two patients, quantitative studies of selected regions of the cortex using a computerized image analyzer disclosed, as in patients with senile dementia of Alzheimer type, a marked reduction in the number of neurons, especially those larger than 90 mu 2. The findings differed from those in Alzheimer dementia, however, in that the cells in the substantia innominata were not reduced and the levels of choline acetyltransferase and somatostatin-like immunoreactivity, determined in one patient, were within normal limits. A variable degree of sponginess of the upper layers of the cortex was attributed to attrition of pyramidal cell dendrites, observed in the one patient in whom Golgi study was successful. Because of severe degeneration of the substantia nigra in all three, the disease in these patients may represent a subset of motor neuron disease or a multisystem atrophy.

Presenile dementia with motor neuron disease in Japan: clinico-pathological review of 26 cases

The clinico-pathological findings of 26 cases of presenile dementia with motor neuron disease in Japan are reviewed. The characteristic features include: (1) Progressive dementia with slowly progressive onset in the presenile period. (2) Neurogenic muscular wasting during the course of illness. (3) A duration of illness to death of from one to three years. (4) Absence of extrapyramidal symptoms and definite sensory deficits. (5) No characteristic abnormalities in the CSF or EEG. (6) No known parental consanguinity of familial occurrence. (7) Non-specific mild degenerative changes throughout the CNS without evidence of cerebrovascular disease or primary degenerative dementia, but with the presence of pathological findings of motor neuron disease. The possibility that this is a new disease entity is suggested.

Somatosensory evoked potentials in amyotrophic lateral sclerosis

Forty five patients with amyotrophic lateral sclerosis were investigated, by means of somatosensory evoked potentials, in order to detect the presence of subclinical sensory changes. Cervical SEPs from the median nerve and cortical SEPs from the median and tibial nerve were recorded, showing a delay of N13 and subsequent components; the latency of the first constant cortical potential was also increased in many patients. Only the SEPs from the tibial nerve showed a decrease of amplitude. These results suggest a pathological slowing of conduction along the central sensory pathways in amyotrophic lateral sclerosis.

The association of motor neuron disease and Alzheimer-type dementia

An elderly woman is described who developed senile dementia of the Alzheimer type, followed within eight months by classical and electromyographic features of sporadic motor neuron disease. Although amyotrophic lateral sclerosis is generally believed to affect the voluntary motor system and spare intellectual function, with the exception of certain familial forms and geographic isolates in the Pacific, pathological involvement of the cerebral cortex and posterior columns has often been demonstrated. A small number of cases of concomitant amyotrophic lateral sclerosis have been reported, but an association has not thereby been proven. With the incidence of dementia increasing, it is possible that epidemiologic studies may show an increase in the incidence of motor neuron disease, and thereby suggest an association. A unitary hypothesis for causation of amyotrophic lateral sclerosis, Parkinson's disease, and Alzheimer's disease has been proposed. Closer investigation of patients with motor neuron disease for dementia, and inquiry into the incidence of motor dysfunction in demented patients, may yield evidence in support of such a hypothesis.

Familial amyotrophic lateral sclerosis: features of multisystem degeneration

Two sibling cases of familial amyotrophic lateral sclerosis (ALS) revealed degeneration usually associated with other systemic degenerative disorders. The changes in the 41-year-old sister were compatible with those reported in other familial ALS cases affecting the upper and lower motor neurons, posterior columns, and spinocerebellar tracts. The 45-year-old sister revealed more wide-spread degenerative changes involving not only motor neuron systems, but also proprioceptive, general somatic afferent and spinocerebellar afferent systems. Intracytoplasmic hyaline inclusions were observed in the oculomotor nuclei. Clinical manifestations of urinary disturbance and oculomotor impairment seldom seen in sporadic ALS were interpreted to be due to the unusual distribution of the morbid process. These pathologic findings suggest that familial ALS may be a multisystemic degenerative disorder, frequently involving the spinocerebellar tracts, but occasionally involving other systems as well.

Motor neuron disease in the Province of Turin, Italy, 1971-1980

The incidence and prevalence of motor neuron disease (MND) in the Province of Turin, North-West Italy, were investigated for the period 1971-1980. The crude incidence rate of MND was 0.67/100,000/year. The annual incidence rate, age and sex adjusted to the Italian population in 1971 was 0.69 cases per 100,000 inhabitants, 0.94 for men and 0.45 for women, with a male to female incidence ratio of 2.09:1. The prevalence of MND was 2.62/100,000, 3.57 for males and 1.71 for females. The mean age at the time of diagnosis was 55.6 years. Annual incidence rates increased with advancing age. Amyotrophic lateral sclerosis was found to be 4 times more frequent than progressive muscular atrophy (0.53/100,000/year v. 0.14/100,000/year). The distribution of MND was uneven in the Province suggesting a proportional relationship to the distribution of population density. Possible explanations of this finding are discussed.

Adult spinal muscular atrophy. A report of four cases

Four cases of spinal muscular atrophy (SMA) are reported, 3 with detailed autopsy findings. These are compared with 2 cases of typical amyotrophic lateral sclerosis (ALS) with neuropathological data. The 3 autopsy cases of SMA only showed decreased numbers of anterior horn cells in the spinal cord, with no change in the cortical pyramidal cells, including the Betz cells, and no degeneration of the pyramidal tracts, while the ALS cases showed loss both of lower and upper motor neurons and degeneration of the pyramidal tracts. In our opinion, the infantile, juvenile, adult, and late-life forms of SMA are really a single disease entity that occurs at varying ages and is separate from ALS. The term lower motor neuron disease would be preferable because the lesions are not limited to the spinal cord, but also occur in the brain stem.

Syndromes of amyotrophic lateral sclerosis and dementia: relation to transmissible Creutzfeldt-Jakob disease

A review of over 2,000 cases of Creutzfeldt-Jakob disease and related disorders in the literature and our own files yielded 231 cases of dementia with early lower motor neuron signs. The clinical-pathological profiles of the 231 cases were distinctly different from those of cases of transmissible Creutzfeldt-Jakob disease: the patients had a longer illness, and their brains lacked the typical spongiform change. Brain tissue from 33 of these patients has been inoculated intracerebrally into nonhuman primates, but only 2 atypical cases transmitted a spongiform encephalopathy; 23 have been incubating from three to twelve years and can be considered negative transmission experiments. The findings suggest that most cases of dementia associated with early amyotrophy are more closely related to classic amyotrophic lateral sclerosis than to transmissible Creutzfeldt-Jakob disease and do not deserve the label of "amyotrophic Creutzfeldt-Jakob disease." When lower motor neuron involvement occurs in transmissible Creutzfeldt-Jakob disease, it is usually late and accompanied by signs of a more fulminant cerebral and cerebellar involvement.

Progressive bulbar paralysis in childhood: a case report

The case of a progressive bulbar paresis in a nine and a half year old child is reported. The first symptoms were present at birth; however, the subsequent evolution was very low. Lesion of the motor nuclei of the V, VII, IX, XII, cranial nerves was evident on electromyographic investigation. Damage to the acoustic brain stem pathway was documented by the brain stem evoked potentials although audiometry was normal. No other neuronal systems or districts appeared to be damaged. The case suggests Fazio-Londe disease, although the involvement (albeit partial) of the auditory pathways recalls Van Laere syndrome. This supports the view that motor neuron disease in infancy is not an autonomous entity but a variant in a wide spectrum of progressive neuronal diseases.

Creutzfeld-Jakob disease: clinical, EEG and neuropathological findings in a cluster of eleven patients

10 of 11 Creutzfeld-Jakob disease patients were seen between February 1975 and November 1979. Whilst the clinical and EEG findings were uniform, the neuropathological changes were not: astrogliosis was always diffuse and widespread but the other typical changes (neuronal loss and spongiosis) varied greatly both in degree and location.

Chronic asymmetrical spinal muscular atrophy

The clinical and neurophysiological features of 18 cases of chronic asymmetrical spinal muscular atrophy are described. These were patients presenting with asymmetrical neurogenic atrophy involving one or more limbs who had no evidence of pyramidal tract dysfunction after 3 or more years of symptoms. There were twice as many males as females and the mean age of onset of the disorder was about 32 years. None of the patients had bulbar involvement. The tendon reflexes tended to be depressed. The distribution of muscle weakness in the limbs was very variable, and only slowly progressive. In 5 cases symptoms and signs were confined to the hands and forearms. Motor nerve conduction velocities to wasted muscles were slightly reduced but there was no evidence of generalised neuropathy. A diagnosis of chronic asymmetrical spinal muscular atrophy, as opposed to that of classical motor neurone disease, is favoured by an age of onset under 40 years, an absence of pyramidal signs or bulbar involvement after 3 years or more of symptoms, and depressed or absent tendon reflexes. The 2 conditions appear to be clinically distinct and prognosis is considerably better in chronic asymmetrical spinal muscular atrophy. The aetiology of this condition in unknown; it may be of relevance that 2 patients in this series had close relatives with Werdnig-Hoffmann disease.

Cerebral atrophy in motor neuron disease evaluated by computed tomography

Thirty-two (64%) of 50 patients with motor neuron disease showed various patterns of cerebral atrophy (cortical, ventricular or both) at CT examination. The incidence of cerebral atrophy, particularly cortical atrophy, in motor neuron disease was greater than in a matched control group.

Macroglobulinemia with peripheral neuropathy simulating motor neuron disease

A 48-year-old man with an IgM plasma cell dyscrasia died after 14 months of symptoms and signs typical of motor neuron disease, including widespread fasciculation and normal sensation. Two laboratory results were atypical: cerebrospinal fluid protein content of 132 mg/dl and slow motor nerve conduction. At autopsy, no loss or atrophy of anterior horn neurons was found; instead, degeneration of ventral and dorsal roots and retrograde changes of chromatolysis in motor neurons implied peripheral neuropathy. Most reported cases of neuropathy associated with plasma cell dyscrasias have been sensorimotor or purely sensory, but there have been 14 previous cases of motor disorders.

Abnormal proximal axons of Clarke's neurons in sporadic motor neuron disease

Filamentous axonalmasses, similar to the abnormal enlargements found in the ventral horns, were found in Clarke’s nucleus in six cases of sporadic A LS. Clarke’s nucleus is generally thought to be normal in sporadic A LS, but the present findings, in conjunction with distal spinocerebellar degeneration which is often described, suggest that this system is also pathologically involved.

Animal model of human disease: motor neuron disease: spinal muscular atrophy and amyotrophic lateral sclerosis

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Amyotrophic lateral sclerosis: a study of systemic complications in autopsy cases in Japan

In a retrospective study involving 277 autopsy cases of amyotrophic lateral sclerosis (ALS) which had been published in the Annual of the Pathological Autopsy Cases in Japan, an investigation was made of concurrent visceral lesions. The results indicated that complications involving the digestive organs, urinary tract and supportive connective tissues were less frequent in ALS than in patients with degenerative diseases of the central nervous system who served as controls. Since a similar discrepancy was observed between patients with ALS and with encephalitis, it was postulated that the difference in incidences might not be simply explained by differences in patients' ages and the duration of illness.

Motor neurone disease with elevated cerebrospinal fluid protein

The correlation between age and CSF protein in 38 patients with pathologically proven motor neurone disease was the reverse of that described for normal subjects by Tibbling et al in 1977. Eight had CSF protein ranging from 0.75 g/1 to 1.52 g/L. These patients were younger, but other clinical and gross and light microscopy pathological features were not significantly different from those with lower CSF protein. Transudation from serum may be only one of the mechanisms underlying this elevation in CSF protein.

Brain lesions in Friedreich's ataxia

An estimate is given of the frequency of pathological changes (assessed by cell populations and from myelin staining) in the brains of 15 cases of Friedreich's ataxia. Mention is made of the special problem of distinguishing primary degenerative lesions from those due to circulatory disturbances arising from the patients cardiac disease.

Ballistic elbow flexion movements in patients with amyotrophic lateral sclerosis

Patients with amyotrophic lateral sclerosis made stereotyped 20 degrees elbow flexion movements as rapidly as possible while surface EMG was recorded from biceps and triceps. The characteristic ballistic movement EMG pattern could be recognised in almost all the patients. The first agonist burst and the first antagonist burst, which are normally limited in duration, were prolonged in patients with clinical signs of pyramidal tract disease or alpha motor neurone disease or both. Prolongation of these components permits the muscles to generate sufficient forces to accomplish the movements.

Creutzfeldt--Jakob disease

The laboratory transmission to animals of an apparently degenerative disease of the nervous system, Creutzfeldt-Jakob disease (CJD), is now well established. Important questions arising from this observation are the possibility of natural transmission or infectivity and the existence of other similarly transmissible diseases. Epidemiological studies have revealed some possible clusters of CJD and also an association with previous craniotomy, but there is no definite evidence of natural infection. A few instances have been reported of experimental CJD in animals following inoculation with material from Alzheimer's disease, but apart from this there is so far no evidence of transmission of any other form of degenerative nervous disease.

Abnormalities of Bell's phenomenon in amyotrophic lateral sclerosis: a clinical and electrophysiological evaluation

A clinical and electromyographic study of oculomotor function was carried out in a series of 24 patients with amyotrophic lateral sclerosis (ALS). In 15 cases an alteration of Bell's phenomenon was found. In addition, three patients showed some impairment of conjugate ocular motility in the form of upward gaze paly. All cases had preserved oculocephalic reflexes in the vertical and horizontal planes. On clinical and electromyographic grounds, three degrees of altered Bell's phenomenon are suggested: attenuated (short and unsustained upward displacement of the eyeballs after forced closure of the eyelids), abolished (no upward displacement), and inverted (downward instead of upward displacement of the eyes). These oculomotor alterations were not directly related to the type of ALS at onset of the illness, nor with its duration. However they were correlated with the relative degree of the clinical bilateral pyramidal tract signs at the supraspinal level. The common involvement of the corticogeniculate tract in ALS could explain the unexpectedly high incidence of alteration of Bell's phenomenon found in this disease, but is is non-specific and similar lesions from different causes may also produce it.

Werdnig-Hoffmann disease: proposal of a pathogenetic mechanism

Light and electron microscopic study and morphometric analysis were performed on the spinal cords and roots from six cases of acute Werdnig-Hoffmann disease and four control cases, in search of the pathogenesis of the selective motor neuron changes considered primarily responsible for Werdnig-Hoffman disease. This investigation posits a centrifugal traction mechanism based upon the discovery of cylindrical outgrowths of glial bundles, selective loss of large myelinated fibers, and axonal degeneration in the proximal portion of anterior spinal roots (and to a lesser extent in posterior spinal roots) in all six disease cases. This traction mechanism exerts principally upon anterior spinal nerve roots and can account for morphologic and morphometric data characteristically ascribed to Werdnig-Hoffmann disease.

Lower motor neuron disease with spinocerebellar degeneration

A patient with polymyositis responded initially to steroid therapy. A muscle biopsy disclosed features of primary myopathy and group atrophy. The patient became refractory to therapy and died with relentlessly progressive weakness. The autopsy disclosed lower motor neuron involvement and degeneration of the spinocerebellar tracts. There was loss of Purkinje cells, which may have occurred secondary to an anoxic episode prior to death. The case is unique because of the limited involvement of the lower motor and spinocerebellar systems.

Motor neurone disease with neurofibrillary tangles in a Brazilian woman

The occurrence of neurofibrillary tangles in both the cerebral cortex and brain stem is typically seen in the Guam type of amyotrophic lateral sclerosis, but is exceedingly rare in the classical form of the disease. Only 3 cases of sporadic amyotrophic lateral sclerosis with such histopathologic features have so far been reported, all in the United States. A 49-year-old Brazilian woman had an 18-month history of amyotrophic lateral sclerosis involving predominantly the left-sided extremities with prominent bulbar signs. Autopysi disclosed moderate to severe loss of motor neurones in the hypoglossal nuclei and anterior spinal horns, absence of pyramidal tract demyelination, depigmentation of the substantia nigra and numerous neurofibrillary tangles in the hypothalamic region, parahippocampal gyrus, reticular substance of the mesencephalon and pons and in some brain stem nuclei. The topographical distribution of these changes was closely similar to that of Guamanian amyotrophic lateral sclerosis.

Preservation of a certain motoneurone group of the sacral cord in amyotrophic lateral sclerosis: its clinical significance

Histopathological description of a special nerve cell group of the sacral spinal cord in five cases of amyotrophic lateral sclerosis is presented. Remarkable preservation of this group of neurones (the X group of Onuf) was noted in each case, and this is discussed with particular reference to vesicorectal function, since it is well known that the function of bladder and rectal sphincters is often intact until the latest stage of the illness.

Familial amyotrophic lateral sclerosis with dementia: a second canadian family

A family with adult-onset amyotrophic lateral sclerosis (ALS) and dementia is described. The father presented with lower motor neurone disease affecting the legs. A son presented with bulbar paralysis. Neither developed dementia. A daughter presented with spastic right lower limb weakness. Two years later, she developed a rapidly progressive mental disorder. Her cortical pathology had a distinctive fronto-temporal distribution. The rarity of published reports on ALS with dementia in families outside the Western Pacific and the factor of parental consanguinity conspired to make genetic counseling for this family difficult.