2024 Workshop Handout Bundle-W21RTA NCS Pitfalls Bassam

W21RTA NCS Pitfalls Bassam

Pdf Summary

The document, authored by Dr. Bassam A. Bassam and others, discusses various pitfalls encountered in nerve conduction studies (NCS) during electrodiagnostic procedures. These pitfalls, often overlooked in standard textbooks, can arise due to instrumentation issues, technical errors, physiological factors, and anomalies in nerve anatomy. Addressing them is critical to ensuring accurate diagnoses of neuromuscular disorders.<br /><br />Key pitfalls include:<br />1. <strong>Instrumentation and Technical Factors</strong>: Errors can stem from inappropriate amplifier settings, filters, recording electrodes, and stimulating electrodes. Incorrect settings can distort responses, and instability in electrodes can induce artifacts, leading to erroneous interpretations.<br /><br />2. <strong>Filters Settings</strong>: Incorrect low- and high-frequency filter settings can distort the biologic signals (SNAP and CMAP), giving a false impression of pathology.<br /><br />3. <strong>Recording Electrodes</strong>: Proper placement of active and reference electrodes is crucial. Misplacement can result in inaccurate readings or waveforms, affecting diagnostic accuracy.<br /><br />4. <strong>Stimulating Electrodes</strong>: Improper handling can lead to stimulus artifacts, adjacent nerve stimulation, and issues like anodal block.<br /><br />5. <strong>Nerve Conduction Determination</strong>: Variability in amplitude, number of stimulation sites, interstimulus distance, and normative data considerations can affect conduction velocity calculations, potentially leading to incorrect conclusions.<br /><br />6. <strong>Physiological Factors</strong>: Factors such as temperature, age, gender, and height can significantly impact NCS results. For example, lower temperatures can slow nerve conduction velocities and alter waveforms, while factors like age and gender can influence baseline normative values.<br /><br />7. <strong>Anomalies</strong>: Anatomic variations like the Martin-Gruber anastomosis can affect NCS readings and require careful consideration to avoid diagnostic errors.<br /><br />The conclusion emphasizes the importance of recognizing and correcting these pitfalls to avoid misdiagnosis. Practitioners need to replicate normative study conditions accurately and be aware of the potential for false positives and negatives. Understanding the influences of various factors and proper handling of technical aspects are critical for accurate nerve conduction studies and electrodiagnostic medicine.

Keywords

nerve conduction studies

ncs

electrodiagnostic procedures

instrumentation issues

technical errors

physiological factors

nerve anatomy anomalies

diagnostic accuracy

electrode placement

filter settings

neuromuscular disorders

nerve conduction studies

nerve conduction study

ncs