Diseases of the aorta and surgery of the aorta can produce spinal cord damage. There are major variations in blood supply to the spinal cord between individuals. The spinal cord may be tamponaded by increased spinal fluid pressure subsequent to clamping the aorta. Both of these factors may contribute to spinal cord infarction. The available methods and procedures to protect the spinal cord during surgery are discussed.

The planarian is the simplest living animal having a body plan of bilateral symmetry and cephalization. The brain of these free-living flatworms is a biiobed structure with a cortex of nerve cells and a core of nerve fibres including some that decussate to form commissures. Special sensory input from chemoreceptors, photoreceptor cells of primitive eyes, and tactile receptors are integrated to provide motor responses of the entire body, and local reflexes. Many morphological, electrophysiological, and pharmacological features of planarian neurons, as well as synaptic organization, are reminiscent of the vertebrate brain. Multipolar neurons and dendritic spines are rare in higher invertebrates, but are found in the planarian. Several neurotransmitter substances identified in the human brain also occur in the planarian nervous system. The planarian evolved before the divergence of the phylogenetic line leading to vertebrates. This simple worm therefore is suggested as a living example of the early evolution of the vertebrate brain. An extraordinary plasticity and regenerative capacity, and sensitivity to neurotoxins, provide unique opportunities for studying the reorganization of the nervous system after injury. Study of this simple organism may also contribute to a better understanding of the evolution of the human nervous system.

Twelve fatal cases of encephalopathy associated with sepsis were examined in a ten-year retrospective study. The sources of infection and organisms isolated were variable. Six of the patients had focal neurologic signs; five had seizures. The level of consciousness varied from drowsiness to deep coma, and electroencephalograms revealed diffuse or multifocal abnormalities. Computed tomographic head scans and cerebrospinal fluid examinations were usually unremarkable. Eight patients had disseminated microabscesses in the brain at autopsy. Four patients had proliferation of astrocytes and microglia in the cerebral cortex, a feature associated with metabolic encephalopathies. Additional findings included cerebral infarcts, brain purpura, multiple small white matter hemorrhages, and central pontine myelinolysis. Although sepsis may cause encephalopathy by producing disturbances in cerebral synaptic transmission and cerebral energy production through a toxic mechanism, bacterial invasion of the brain with the formation of disseminated microabscesses is also an important cause.

Visual evoked response (VER), auditory brainstem evoked response (ABER), somatosensory evoked response (SSER), blink reflex and electronystagmographic (ENG) investigative methods were applied to a group of 89 patients with Multiple Sclerosis (MS) and Optic Neuritis (ON). The MS patients were classified as definite (n = 31), probable (n = 31) and possible (n = 27).

The aim of this study was to determine the diagnostic value of the five electrophysiological tests in MS. VER and ABER recordings were found to reveal the highest number of asymptomatic abnormalities (33 and 31 percent respectively). The combination of VER, ABER and ENG revealed all possible electrophysiological disorders. As these tests are completely non-invasive it is proposed, that a combination of two of these three tests is useful for the detection of a second silent lesion in patients with suspected MS showing purely spinal signs (VER, ENG, ABER) and/or a history of uncomplicated ON (ABER, ENG).

Dystonic torticollis has been treated with local injections of botulinum toxin in a single blind study of 12 patients. A significant decrease of abnormal movements was recorded, and pain improved. Further studies are desirable to define the optimum dosage and site for injections, and the long term effects of repeated injections.

A review of patients with epilepsy showed that 5.9% had seizures exclusively in sleep (ES) and 4.7% had seizures predominantly but not exclusively in sleep (PS). These groups were compared with a group (W) with seizures mainly in wakefulness. The following significant differences were obtained: 1) generalized convulsions predominated in the ES while partial seizures were more common among PS and W patients, 2) seizures occurred less frequently in the ES group, and 3) more W patients had EEGs with generalized epileptiform activity and positive family histories for epilepsy.

We suggest the lower frequency of seizures in the ES group and the declining prevalence of sleep epilepsy are due to: 1) the high proportion of generalized as opposed to partial seizures in sleep and 2) more effective control of generalized seizures compared to partial seizures by modern anti-epileptic drug management.

A 27-year-old woman presented with hemotomyelia during pregnancy. Needle drainage of the spinal cord was followed by relief of symptoms. Symptoms recurred during a second pregnancy 4 years later and she presented with an avascular mass in the midcervical spinal cord. This lesion proved to be hemangioma calcificans, a densely calcified and ossified variant of cavernous angioma.