Ultrasound of nerve and muscle.

Over the last two decades, ultrasound has developed into a useful technology for the evaluation of diseases of nerve and muscle. Since it is currently not used at by the majority of clinicians involved in diagnosis or care of patients with neuromuscular disorders, this review briefly describes the technical aspects of ultrasound and its physical principles. It relates normal muscle anatomy and movement to ultrasound images in the axial and sagittal planes and follows with a discussion of ultrasound findings in chronic muscle disease. These include evident atrophy and the loss of the hypoechoic architecture of normal muscle tissue. It highlights evolving uses of the technique to measure other pathologic changes in disease including altered muscle dynamics. With high-resolution instruments nerve imaging has now become standard, and the relationships of median nerve anatomy and observations of static and dynamic images from ultrasound are reviewed. Changes seen in carpal tunnel syndrome include significant increases in the cross-sectional area of the nerve just proximal to the site of compression, loss of hyperechoic intensities within nerve, and reduced mobility. Preliminary use of the technique for the study of other nerves is reviewed as well. Ultrasound is an ideal tool for the clinical and research investigation of normal and diseased nerve and muscle complementary to existing diagnostic techniques. As the technology continues to evolve, it will likely assume a more significant role in these areas as those most able to exploit its potential, clinical neurophysiologists and neuromuscular clinicians, incorporate its use at the bedside.     

Orbital colour Doppler imaging in chronic ocular ischaemic syndrome

Background: The clinical syndrome of chronic ocular ischaemia may be difficult to diagnose due to its wide range of non-specific presentations, and its diagnosis often implies the presence of underlying severe carotid occlusive disease. Colour Doppler imaging (CDI), a recent advance in ultrasonography that allows for colour-encoded blood flow data of a vascular structure to be displayed simultaneously on a conventional real-time gray-scale B mode image, has been used in the assessment of ocular and orbital vasculature. Method: Four patients with chronic ocular ischaemic syndrome whose diagnoses were aided by CDI are presented. Results: Orbital CDI was successful in confirming the diagnosis in all four cases. Reversal of blood flow in the ophthalmic arteries was demonstrated. Central retinal vessels were not detected with CDI in all four patients with complete occlusion of the ipsilateral internal carotid artery. One of the four patients had intermittent reversal of ophthalmic arterial flow ipsilateral to the 60% stenosed internal carotid artery. Conclusion: This non-invasive technique is an excellent alternative to invasive vascular studies such as angiography for the diagnosis and evaluation of the chronic ocular ischaemic syndrome.     

Early diagnosis of herpes zoster by polymerase chain reaction

BACKGROUND: Herpes zoster is a common disease caused by the varicella-zoster virus. The use of virostatic agents as early as possible is necessary in shortening zoster-associated pain. OBJECTIVES: Rapid diagnosis is necessary for the optimal efficacy of antiviral therapy. The diagnosis in the early stage of infection is often difficult. METHODS: In the present study skin biopsies of patients with herpes zoster and unclear skin changes were analysed by detecting viral DNA using the polymerase chain reaction (PCR) in order to amplify open reading frames (ORF) 14, 29 and 63. RESULTS: Varicella-zoster virus DNA could be detected with PCR of all three ORF not only from blisters but also from erythematous skin. CONCLUSIONS: PCR is the method of choice for the viral diagnosis in herpes zoster before blister eruption.     

Headache in systemic lupus erythematosus: a controlled study

Intractable headaches, the so-called 'lupus headaches', have been long thought of as a common and characteristic manifestation of systemic lupus erythematosus (SLE). Seventy-eight patients with SLE, including 10 patients with definite central nervous system (CNS) involvement, and 89 healthy individuals matched for age, sex and socioeconomic status, were studied by a specific questionnaire addressing the characteristics and type of headache. Clinical features of SLE, neurological manifestations and treatment, disease severity and autoantibody profiles were correlated to the presence of headache. One year prevalence of headache was similar between patients (32%) and otherwise healthy individuals (30%). No significant differences regarding frequency, family history of headache and need for analgesic medication were observed. Headache refractory to analgesic treatment, but responsive to corticosteroid regimen, was recorded in only one patient. Clinical and serological features of SLE, including Raynaud's phenomenon and the presence of anticardiolipin antibodies, were not significantly different between headache sufferers and non-sufferers. In the majority of patients reporting headache, anxiety and/or depression co-existed. Episodic tension headache was the most frequent type, while migraine was traced in a quarter of headache sufferers. Neither the presence nor the clinical type of headache was related to, or predictive of, the development of seizures or psychosis. These results indicate that headache is not specifically related to SLE expression or severity, and suggest that accepting the presence even of a severe headache as a neurological manifestation of SLE in the absence of seizures or overt psychosis may result in overestimation of the disease status.      

Posterior fossa arachnoid cyst presenting with an isolated twelfth nerve paresis. Case report and review of the literature.

An unusual case of a posterior fossa arachnoid cyst containing atypical fluid is described in a patient presenting with an isolated ipsilateral twelfth nerve paresis. Despite the chronicity of symptoms, surgical decompression resulted in a satisfactory functional recovery.     

Characterization of latent and active forms of cartilage proteinases produced by normal immature rabbit articular cartilage in tissue culture

Cultured tissue slices from normal immature rabbit articular cartilage released latent neutral metalloproteinases into serum-free medium. On activation with 4-aminophenylmercuric acetate, these metalloproteinases could degrade collagen, proteoglycan, and gelatin. Also produced were an acid proteinase with the properties of cathepsin D and an inhibitor of the neutral metalloproteinases. The appearance of both the proteinases and the inhibitor in the culture medium could be prevented by incubation of cultures with cycloheximide. The active and latent forms of the proteinases were characterized using Ultrogel AcA 54 chromatography.