Importance of Measuring Manual F-Wave Persistence - Original Article

Objective: Many of the F-waves were not marked correctly by automatic computerized processes while doing nerve conduction study. This study was done to investigate if there is any importance to measure the F-wave persistence values manually while doing nerve conduction studies.Materials and Methods: A total of 60 patients (18 men) aged 19-65 (average 37±11.5) years were included and 78 nerve conduction studies were performed for analysis of ulnar nerve F-wave parameters; the subjects had normal results of the motor and sensory ulnar nerve conduction studies. F-wave persistence was recorded automatically by a computer (automated persistence). We observed that the software did not mark few F-waves correctly, therefore, we counted them manually (manual persistence).Results: Ulnar nerve F-wave persistence, measured manually and automatedly, showed significant difference when analyzed by Wilcoxon signed-rank test (Z=3.24, p<0.005), indicating significantly increased persistence, when calculated manually, in comparison with the automated persistence. In 78 nerve conduction studies, the manual persistence was greater than the automated persistence in 25, less than the utomated one in 5 and equal to it in 48 measurements.Conclusion: Manual persistence is recommended for F-wave persistence measurements whenever needed. This study suggests also that there is a necessity for improvement in the software for the F-wave studies. Turk J Phys Med Rehab 2010;56:186-9.