Comparison of perception threshold testing and thermal‐vibratory testing

Abstract

Current perception threshold testing (CPT) is thought to selectively activate and measure three types of afferent nerves. However, it has not been standardized or compared with better-studied methods of sensory testing. Our objectives were to determine the relationship between CPT (2000 Hz, 250 Hz, 5 Hz) and quantitative sensory testing (QST) using vibratory and heat thresholds, and to assess the test-retest reliability of both methods. Twenty-seven healthy women were enrolled. Each woman underwent CPT and QST on the volar part of the arm. Sensory thresholds were determined by the method of limits; 20 women underwent repeated CPT testing and QST after 1 week to determine test-retest reliability. Thermal thresholds were moderately correlated with CPT at 5 Hz (rho = 0.49, P = 0.009), as were vibratory thresholds and CPT at 2000 Hz (rho = 0.5, P = 0.008). In contrast to CPT measurements, warm and vibratory and cold thresholds were correlated 1 week apart (rho = 0.73, P = 0.0001; rho = 0.83, P = 0.0001; and rho = 0.47, P = 0.0037, respectively). CPT testing and QST seem to be measuring similar afferent nerve-fiber populations, but QST has better test-retest reliability than CPT testing, justifying its role in clinical or research studies.

Current perception threshold and reaction time in the assessment of sensory peripheral nerve fibers through sinusoidal electrical stimulation at different frequencies

“…However, frequency-based neuroselectivity is far from consensus. In the literature there are several studies that agree with the existence of such phenomenon (Lowenstein et al, 2008;Masson et al, 1989;Matsutomo et al, 2005;Nishimura et al, 2004;Tierra-Criollo et al, 2006), and others that disagree (Tack et al, 1994;Vinik et al, 1995).…”

Patients with painful bladder syndrome have altered response to thermal stimuli and catastrophic reaction to painful experiences

“…This finding of hyposensitivity at T12 contrasts with the results of our prior study carried out using CPT that found no difference in sensitivity, 9 a discrepancy that is not surprising given the known inconsistency in findings when these two testing modalities are utilized on the skin: one study comparing CPT and QST demonstrated only a moderate correlation between CPT at 5 Hz and thermal stimuli and also demonstrated that thermal stimuli had superior reproducibility when tested on the hand. 32 The finding of hyposensitivity to stimuli is not novel, as similar hyposensitivity has been documented in patients with IBS, but has not been found in PBS patients before. Similar hyposensitivity to additional stimuli in the setting of chronic background pain has been documented in other studies of chronic pain [33][34][35] and is thought to reflect either activity of diffuse noxious inhibitory control (DNIC) mechanisms, 36 and/or adaptation, 31 in which additional stimuli are perceived as relatively mild because they occur against a background of chronic pain.…”

“…This finding is consistent with our prior findings that PBS patients had decreased habituation to non-noxious repeated supra-threshold CPT at the same dermatomes. 9 Habituation, a decrease in responsiveness to a stimulus when that stimulus is presented repeatedly or for a prolonged time, is an important mechanism that allows us to ignore non-noxious stimuli, 32,33 and is thought to be mediated by cellular plasticity with depression of responses during repetitive stimulation. Habituation is usually described in the context of repetitive stimuli rather than continuous stimuli we applied in this study, but similar mechanisms may apply.…”

“…The threshold value in all cases was conducted with two different modalities of heat and vibratory stimuli following a course of training stimuli, which was given to familiarize the women with the measurement. For thermal thresholds, the temperature of the surface plate was elevated from a level of 32 C at a rate of 1 C/sec. The rate of vibratory amplitude change was 1 mm/sec, starting from a level of zero.…”

Thermal quantitative sensory testing to assess the sensory effects of three local anesthetic solutions in a randomized trial of interscalene blockade for shoulder surgery

“…Furthermore, patients detect thermal stimuli more easily than CPT stimuli. 30,31 Finally, this method is only a semiobjective test in that it requires subjective feedback from patients regarding the detection of electrical stimulation.…”