On the controversies about clinical use of EEG brain mapping.

Quantitative EEG analysis, often called EEG Brain Mapping, consists of a large variety of separate techniques. Most of these techniques have demonstrated research uses, but few have been shown to have clinical applications that actually impact patient care. Substantial problems exist that can interfere with routine clinical applications. These include a variety of artifacts, confounding clinical problems, diversity of techniques and statistical issues. Existing medical literature suggests several areas where there are clinical uses at this time. EEG Brain Mapping can be used as a testing technique to determine abnormality and perhaps as a monitoring tool, too. It should be viewed as complementary to neuroimaging techniques, rather than a competitor. Those who introduce costly new technology bear the burden of proof for demonstrating its usefulness and cost-effectiveness. Evaluation of new tests should be based on several principles outlined here. EEG Brain Mapping, when used for clinical purposes, should be read together with the accompanying traditional polygraph EEG record. Reproducibility of results should be demonstrated, and artifacts, normal variants and other problems must be identified or avoided. The reader must recognize that features noted on statistical tests do not necessarily imply that pathology exists. Reporting results and clinical implications should be done carefully, thoroughly and with appropriate caution. Results are often quite nonspecific. The user must have skills, knowledge and abilities for reading polygraph EEG as well as additional experience and knowledge about quantitative EEG techniques and problems. Experts must remain careful and responsible about introducing EEG Brain Mapping into routine clinical practice.