The effect of prolonged pain on the course of dark adaptation by the optic analyzer

Abstract

A study was made of the effect produced by chronic pain on the course of dark adaptation of the visual analyzer Sixty persons with pain syndromes of various origin were subjected to examination. Investigation was carried out with the aid of an adaptometer of the ADM model; the light sensitivity thresholds were expressed in optic density units. Comparison of the data obtained with the results of 36 control experiments demonstrated that in prolonged pain the light sensitivity of the visual analyzer decreased along the whole course of adaptation curve by 15–18% of the normal value. A rise in the light sensitivity, gradually reaching the normal values, was noted after elimination of the pain. No deviations from the normal were revealed in cases with periodic transitory sensations of pain.