Also found in: Medical.
a method of measuring chronaxie during the study of excitability in living tissues. The French physician J. Bourguignon introduced the method into clinical practice in 1915.
Chronaximetry is performed with a chronaximeter, which consists of a source of direct current, a series of resistors, and a device for changing the duration of the electric current pulse directed on the given tissue. A decrease in the chronaxie indicates improvement in a tissue’s functional state, and an increase indicates deterioration in the tissue’s state. The method of chronaximetry, which evaluates the functional state of excitable tissues by ascertaining changes in the chronaxie, has significant drawbacks. For example, in determining the chronaxie of muscles a single stimulus is used, a circumstance that does not occur under the normal conditions of the organism’s functioning. When there are pathological changes in excitable tissue, or in cases of narcosis, the chronaxie may decrease when the functional state deteriorates. Consequently, more precise methods of recording the bioelectric activity of excitable tissue, such as electromyography, are more commonly used in clinical practice.
V. G. ZILOV