Chronaxie is the tissue-excitability parameter that permits choice of the optimum stimulus pulse duration for stimulation of any excitable tissue. Chronaxie (c) is the Lapicque descriptor of the stimulus pulse duration for a current of twice rheobasic (b) strength, which is the threshold current for an infinitely long-duration stimulus pulse.

2015年1月7日 · The meaning of CHRONAXIE is the minimum time required for excitation of a structure (such as a neuron) by a constant electric current of twice the threshold voltage.

Chronaxie [edit | edit source] It is the minimum time required for a current of double the intensity of rheobase to stimulate a muscle. Its normal value is below 1ms. Chronaxie is inversely proportional to excitability. Thus, its value is greater for denervated muscles.

The chronaxie of a neuron is the pulse duration at which a neuron is discharged at a current level that is twice the rheobase current, the minimal asymptotic current level at the longest pulse duration (our Fig. 2 A).

A strength–duration curve describes electrode threshold current as function of stimulus pulse duration. Chronaxie is defined as the time on such a strength–duration curve for twice the minimum (rheobase) current needed for very long pulses.

The chronaxie is defined as the minimum pulse duration at an intensity twice the rheobase required for fiber activation. Recently, a group proposed adding patient paresthesia coverage as a variable to the classic strength–duration curve, which allows for optimal programming of the spinal cord stimulation device. 7

Chronaxie is defined as the shortest duration of stimulus required to excite a tissue by a current strength equal to twice of Rheobase voltage. Chronaxie of a tissue is a definite measure of its excitability.

The chronaxie is the time it takes to activate a fiber when the amplitude is twice the rheobase. For two neurons with similar rheobases, the chronaxie gives a measure of the relative excitability of the neurons: shorter chronaxies apply to neurons that are more excitable.

In summary, there were significant differences in rheobase and chronaxie between the paretic and non-paretic sides of hemiplegic stroke patients. Rheobase and chronaxie of the paretic side had greater values than the non-paretic side.

2000年4月1日 · Chronaxie values calculated from voltage-duration data were shown to be 30-40% below those estimated from current-duration data. It was also shown that in the normal range of stimulation amplitudes (up to 7 V) the load impedance …