Comparison of Current Perception Threshold Electrical Testing to Clinical Sensory Testing for Lingual Nerve Injuries

Abstract

We performed a retrospective study of lingual nerve injury assessment comparing the techniques of current perception threshold testing versus clinical sensory testing. We designed and implemented a cross-sectional study and enrolled a patient sample with lingual nerve injuries presenting for treatment to the principal investigator. The predictor variables were clinical sensory testing modalities (ie, temperature, nocioception, vibration, 2-point discrimination, brush stroke, and von Frey monofilament perception). The primary outcome variable was the electrical current perception thresholds of the tongue dorsum (neurometer measurements at 5, 250, and 2,000 Hz). Comparisons were established with the ipsilateral affected and contralateral unaffected lingual nerve distributions. The associations between the clinical sensory testing and current perception threshold measurements were assessed using correlation coefficients, with the level of statistical significance set at P < .05. A total of 40 patients (13 males and 27 females) were included in the present study. The average age of these patients was 34 years (range 13 to 66). Significant correlations were observed between the electrical stimulation thresholds at 2,000 Hz and the 2-point discrimination, reaction to brushing, reaction to vibration, and von Frey fiber thresholds, between the electrical stimulation thresholds at 250 Hz to the nociceptive and thermal thresholds, and between the electrical stimulation thresholds at 5 Hz to thermal stimuli. The significant correlations observed in the present study indicate that current perception threshold can be a complementary or alternative tool in the assessment and evaluation of lingual nerve injuries.