A blind study showing that serum from patients with Alzheimer's disease causes immunolysis of mammalian brain synaptosomes is reported. Control, aged-matched, sera were largely without effect. The immunolysis was directed mainly against cholinergic synaptosomes. The data support the hypothesis that autoimmune mechanisms may operate in the pathogenesis of Alzheimer's disease.

Cerebral edema associated with meningiomas is a rather common phenomenon. A patient with a small meningioma presented with severe cerebral edema, out of proportion to the size of the tumor. During surgery the meningioma was removed and the adjacent edematous brain tissue biopsied. The histopathoiogical study showed conspicuous plasma cell and lymphocyte infiltration in both the tumor and the cerebral edematous tissue. The pathological findings are presented, and the possible mechanism for cerebral edema associated with meningioma is discussed.

Encystment of the fourth ventricle, due to occlusion of the aqueduct as well as the foramina of Magendie and Luschka has been described previously. Partial sequestration such as that encountered in two cases described is a less common entity. In these two cases, the aqueduct of Sylvius was occluded, but the basal foramina (Magendie and Luschka) were patent. We discuss this partial sequestration or communicating hydrocephalus of the fourth ventricle on the basis of MR and CT scan findings. Although computed tomography following water soluble cisternography did diagnose the entity indirectly MRI proved to be a superior tool. It permitted direct visualization of the basal foramina noninvasively.

Chronic aseptic meningitis is a rare manifestation of systemic lupus erythematosus. It may occur early in the course of the disease and sometimes may be the initial symptom. We report a patient with chronic aseptic meningitis associated with systemic lupus erythematosus. Magnetic resonance imaging showed several ischemic lesions and an appearance which was compatible with chronic inflammation of the ependyma of the lateral ventricles.

A 68-year-old man known to have inclusion body myositis underwent a cricopharyngeal myotomy in an attempt to improve his progressive dysphagia. Morphological studies from tissues obtained during this procedure showed the diagnostic features typical of this chronic inflammatory myopathy. To our knowledge this is the first pathological demonstration of inclusion body myositis involving the pharyngeal skeletal musculature.

The results of 3 computed tomography (CT) examinations carried out over a 7 year period and of a post-mortem magnetic resonance (MR) study showed aspects of a white matter disease in a hypertensive patient suffering from vascular dementia. Histopathology revealed the primary cause of dementia to be a white matter degeneration sparing the U fibers. Rarefaction of both the myelin sheaths and the axons was present together with severe thickening of the medullary arteries. These findings support the existence of Binswanger's disease (BD) as a distinct variety of arteriosclerotic dementia. CT and MR imaging are valuable aids for diagnosis. However, since there are many other causes of CT and MR demonstrated diffuse white matter degeneration in the elderly, a conclusive diagnosis of BD requires pathological confirmation.

Three-dimensional reconstruction and ultrastructural studies of classical plaques from the cortex of patients with Alzheimer's disease showed that microglial cells of the plaques are the amyloid-forming cells. The amyloid star of the single plaque represents the product of five or six microglial cells covering about 80% of the amyloid star surface. The amyloid fibers appear to be formed within altered cisterns of the endoplasmic reticulum. Distended cisterns form channels filled with amyloid fibers. Numerous vesicles derived from the Golgi apparatus appear to be attached to or fused with the amyloid-filled channels. Reconstruction of the amyloid star and the microglia cell pole that forms the amyloid star reveals three different zones of distribution of cytoplasmic organelles and amyloid deposits. The peripheral zone comprises channels filled with loosely packed amyloid fibers arranged in a parallel manner. The transient zone consists of a mixture of fusing amyloid channels and products of disintegration of cytoplasmic pockets, dense bodies and fragments of cellular membranes. The core of the amyloid star is composed of condensed, densely packed amyloid fibers that are free of cellular debris. Formation of the three zones supports the idea that the microglia/macrophages are not phagocytes but instead are the cells manufacturing the amyloid fibers.

A rare case of cystic schwannoma occurring in the brainstem in the absence of von Recklinghausen's disease is reported. This appears to be the first case in the literature of a cystic schawnnoma ever described in this location. While the exact origin of this tumor in this unusual location remains uncertain, different hypotheses are discussed and the possible origin of this tumor from perivascular elements in the brainstem is seriously considered.

Although pain is not generally recognized as a symptom of tic disorders, we have seen a number of patients in whom this was a prominent feature, at times even the symptom of greatest concern. The commonest pain complaints are those arising from the actual performance of a tic. Most often this follows directly from the discomfort produced by sudden or repeated extreme exertion. Here the origin of the pain is usually musculoskeletal, though rare examples of neuropathic pain may occur. Pain also may arise from striking or being struck by a moving body part involved in large amplitude tics. Other related painful acts include deliberate self-injury and pain inflicted upon others. A second major category is represented by a smaller number of patients who complain of pain during voluntary efforts to suppress their tics. Finally, there are patients who obtain relief from tics while experiencing pain, to such an extent that they will deliberately provoke pain to obtain its benefit. We feel that pain should be recognized as a common complaint, and occasionally a source of significant disability, in patients with tics.

On rare occasions anticonvulsant medication may cause severe or fatal toxic reactions. This position paper, approved by the Canadian Association for Child Neurology, examines the value of routine blood and urine screening to prevent catastrophic reactions in asymptomatic patients. The basic assumptions of such a screening program are faulty or unproven. Although not definitive, available studies of screening do not appear to support its value. It is recommended that routine blood and urine screening be discontinued in asymptomatic patients. Until such time as further research is able to identify patients at special risk, it is suggested that patients be carefully informed of the early symptoms of severe toxic reactions and report these immediately to a physician.

We studied a 42-year-old woman who had persistent active acromegaly despite conventional therapies. She was treated for 6 months with SMS 201-995. Her mean plasma growth hormone GH values decreased during treatment from 9.1 ± 1.2 to 6.6 ± 1.2 µg/L. One month after the withdrawal of SMS 201-995, the plasma GH level increased to 24.4 µg/L (P < 0.001). This elevation was clinically silent and transitory, as GH levels decreased 8 months later to 6.9 ± 1.3 µg/L. Furthermore, at the beginning of therapy, her intractable headache was completely relieved; however, it progressively resumed under therapy. In conclusion, cessation of SMS 201-995 may be followed in some acromegalic patients by a rebound of plasma GH levels. This rebound suggests that SMS 201-995 decreases GH levels by an inhibition of its release from the pituitary. Furthermore, SMS 201-995 may relieve intractable headache in some acromegalic patients, but tolerance to the analgesic effect may develop.

Since the discovery of a significant depletion of acetylcholine in discrete areas of the brain of patients affected by Alzheimer's disease, attempts at symptomatic therapy have concentrated on acetylcholine supplementation, an approach that is based upon the efficacy of dopaminergic supplementation therapy for Parkinson's disease. Choline, then lecithin, used orally, failed to improve symptoms but the hypothesis that long-term choline supplementation might stabilize the course of Alzheimer's disease remains to be tested. Nerve growth factor may also offer that possibility. Bethanechol administered intracerebroventricularly did not help when a fixed dose was used but individual titration of more selective muscarinic agonists may prove more effective. In this article we report that tetrahydroaminoacridine (THA), given together with highly concentrated lecithin, appears to bring improvement in cognition and in functional autonomy using the Mini Mental State and the Rapid Disability Rating Scale-2 respectively, without change in behavior as reflected by the Behave-AD. Double-blind cross-over studies are in progress to establish its efficacy. Improvement in study design and means of assessment of cognition, functional autonomy and behavior have been made possible by these drug trials.

Phenotype Variability in Myotonic Dystrophy Myotonic dystrophy, best known in the French literature as Steinert disease, is a dominantly inherited disorder. When the gene is fully expressed, it shows a characteristic clinical picture. Myopathy and myotonia are the main features, but this is a systemic disease which may involve many other organs such as the central nervous system, eyes, bones, endocrine system, etc. With the complete picture, physical and behavioral features make the diagnosis easy, only to be confirmed by neurological and ophthalmologic examination and/or electromyography. This work reviews the main clinical signs seen in the classical form of the disease. We also want to stress the variability of that picture. Finally, we describe a new dysmorphic sign in myotonic dystrophy: large prominent cupped auricles. Although not recognized, prominauris has been illustrated in a number of publications on myotonic dystrophy. Three of our adult male patients presenting the congenital form of the disease at birth have been investigated to rule out concomitant fragile-X syndrome. Both syndromes include mental retardation and dysmorphic ears. Our patients show the usual testicular atrophy, whereas the fragile-X syndrome includes testicular hypertrophy. Cytogenetic studies were normal. Old clinical description and new physical signs may lack prestige in the perspective of recent molecular biological breakthroughs, but to recognize the disease and help patients live with it will always be the role of practitioners.

We argue against the dominant status assigned to conventional microscopy in the categorization of disorders such as Alzheimer's disease, Parkinson's disease and ALS. As an example we criticize the emphasis that has been placed on correlating the presence of Lewy bodies with the diagnosis of Parkinson's disease. In essence, we submit that Parkinson's disease can exist without Lewy bodies, and Lewy bodies can exist without Parkinson's disease. Nevertheless, we consider that the newer techniques available to histology have led to an important concept that constitutes a shared feature for Alzheimer's disease. Parkinson's disease and ALS; they are all characterized by the deposition of cytoskeletal debris in tissue, so they may perhaps be collectively termed the “Cytoskeletal Disorders”.

Seven French-Canadian cases of clearcut oculopharyngeal muscular dystrophy (OPMD) had their muscle studied for the presence of intranuclear inclusions, and they were all positive. Inclusions of both “mature” and “immature” types were seen in our material. The presence of such intranuclear structures should be added to the criteria of the clinical picture and the family history for diagnosis of a case and inclusion of a family in further genetic studies. Reverse genetic studies of large families and biochemical studies of these intranuclear structures may help to understand the pathogenesis of this common disease in Quebec.