Clinical and experimental neurology
-
Basilar artery occlusion developed in a 34 year old woman 2 months after adopting unusual neck postures during yoga practice. On angiography, her basilar artery was filled with intraluminal clot while the vertebral arteries were normal. We postulate that a severe reduction in blood flow and possibly an intimal tear triggered thrombosis of the vertebral artery and that the final stroke mechanism was artery-to-artery embolism.
-
Because sensory neuropeptides improve survival of critical skin and muscle flaps in rats, skin nociceptive sensory nerve function in blister healing was examined. Sensory nerve ablation by unilateral hindlimb denervation or cutaneous axon reflex enhancement by 14 days systemic nicotine treatment (5 mg kg-1 day-1) decreased and increased, respectively, peripheral motor functions of nociceptive (peptidergic) skin nerves. Effects on nociception were measured by a radiant heat tail-flick test. ⋯ Finally, resting substance P release from blisters, after direct cutaneous nerve stimulation, appears to be enhanced in nicotine-treated rats. Thus nociceptive innervation appears critical for inflammation and rapid healing of blisters in rat skin. The data signal a possible important role for neuropeptides in these processes and question the function of nicotinic receptors on sensory nerves.
-
The diagnosis of median nerve compression neuropathy at the carpal tunnel is usually confirmed by clinical electrophysiology. The classical findings of a significantly slowed median nerve conduction velocity for both sensory and motor fibres, with a prolonged distal motor latency and a reduced amplitude compared to age-related norms are unambiguous, but these criteria are often present only in part. In such cases another quantitative indicator of compression neuropathy would be extremely helpful. ⋯ Further, although both thermal thresholds at the wrist were normal, those on the palm were elevated, cold being significantly raised (P less than 0.02) compared both to warm and to age-matched controls. Correlation of the nerve conduction velocity findings and thermal sensory acuity did not yield significant covariance of the positive and negative findings. Overall the results suggest that detection of preferentially elevated cold perceptual threshold (ie reduced cold sensory acuity) on the skin of the palm may aid in the diagnosis of putative carpal tunnel compression in patients with minimal or ambiguous electrophysiological data and provide a functional index of recovery after decompression.
-
Severe spasticity is a major problem in the rehabilitation of patients with dysfunction of the spinal cord or cerebral hemispheres. Oral baclofen is often effective. ⋯ Over the past 5 years we have developed a program for the use of intrathecal baclofen for severe spasticity, and in relation to this discuss patient assessment, practical aspects of drug administration, complications of therapy and patient benefits. Continuous intrathecal baclofen is a safe and effective adjunct to physical therapy in the management of patients with severe spasticity.
-
Daily salivary anticonvulsant monitoring in epileptic patients with frequent seizures appears a promising, practicable and inexpensive approach which may assist in the management of drug therapy. It offers the possibility of predicting the optimal drug concentration likely to minimise seizure activity in a given patient, and sometimes allows the inference that different anticonvulsant drugs should be tried forthwith. The use of the method is described in one patient who collected daily saliva specimens and recorded any seizure activity over periods of several weeks. ⋯ Saliva was again collected daily over another 3 months. Analysis of the data on this occasion suggested that carbamazepine, in the presence of methylphenobarbitone, may have played little role in seizure prevention, and also predicted the salivary level of phenobarbitone likely to minimise seizures. Unfortunately the patient again could not tolerate the drug doses necessary to attain this phenobarbitone concentration.