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[Microcirculation in the conjunctiva and the nail bed in the aged. Symptomatic and clinico-pharmacologic aspects]
Abstract:
Study of the microcirculation primarily involves assessment of the capillaroscopic findings. In the clinical field, these are mainly obtained from small vessels of the conjunctiva and nail bed. In more recent years, microcirculation has been accompanied as a subject of examination by haemorheology. The study of blood viscosity and red cell deformability is the most promising from the practical standpoint. In the diagnostic and physiopathological evaluation of capillaroscopic findings, importance is attached to differentiation of arterial and venous vessels, the size, shape and configuration of the small vessels, and above all the presence of intravasal red cell clumps. In examination of the nail bed, particular attention is directed to oddities in the shape of the capillary loops, venous stasis and congestion pictures (in decompensated heart disease, for example, and in cor pulmonale), and alterations in the subpapillary plexuses. Examination of the conjunctiva takes account of the presence of tortuous and serpiginous vessels, with pronounced dilatations, as observed in cardiocirculatory decompensation and chronic bronchopulmonary diseases. In arteriosclerosis, tortuosity and dilatation, even as far as the formation of microaneurysms, may be accompanied by the percent of stiff, thin vessels in networks or webs of various sizes. Clinical pharmacology tests, such as those employing vasoactive drugs (xanthinol nicotinate, buflomedyl, cyticholine) are of interest. They result in a marked increase in calibre, with the appearance of collaterals, regression of red cell aggregates, and improved blood flow.