Comparison between sensory testing modalities for the evaluation of afferent nerve functioning in the genital area.

Determine the reproducibility and relationship between current perception threshold testing (CPT) and quantitative sensory testing (QST) in the genital area. Sixteen women underwent CPT and QST of the vagina. CPT was done at 2,000, 250, and 5 Hz (corresponding to A-beta, A-delta, and C fibers, respectively), and QST testing was done using thermal (C fibers), vibratory (A-beta fibers), and cold (A-delta and C fibers) sensation. Ten women underwent repeated testing 1 week later. Thermal and vibratory thresholds correlated with CPT at 5 and 2,000 Hz (rho = 0.77, P = 0.002 and rho = 0.6, P = 0.01, respectively). Repeated thermal, vibratory, and cold thresholds had good concordance correlation (rho_(c) = 0.83, rho_(c) = 0.96, rho_(c) = 0.77). CPT at 5 and 2,000 Hz were also strongly correlated (rho_(c) = 69, rho_(c) = .7). CPT and QST testing stimulate similar afferent nerve fiber populations in the vagina.