Diagnostik von Endplattenstörungen mit Jitter-Bestimmung mit der konzentrischen Nadelelektrode

Zusammenfassung

Bei der Sicherung der Verdachtsdiagnose einer Endplattenstörung ist die Elektrophysiologie schneller als der Antikörpernachweis verfügbar. Zur Verfügung stehen verbreitet die repetitive Nervenstimulation (RNS) und wenig verbreitet die Einzelfasermyographie (sfEMG). Die RNS ist zwar einfach durchführbar aber nicht sehr sensitiv. Die Verbreitung der sfEMG als zuverlässigere Methode hat nach der Abwendung von wiederverwendbaren spezialisierten Nadeln sehr abgenommen, und die Abwandlung der Technik mit Routineausrüstung und der normalen konzentrischen Nadel hat diesen Trend nicht umgekehrt. Wir wollen die technischen und physiologischen Grundlagen der Technik, ihre praktische Durchführung, typische zuverlässige und möglicherweise qualitativ eingeschränkte Signalformen und die Wertigkeit der sfEMG im klinischen Kontext erklären.

Abstract

For diagnosing a dysfunction of the neuromuscular junction, results of electrophysiological tests are more readily available than results of antibody testing. The relevant techniques are repetitive nerve stimulation (RNS) which is in widespread use and single fiber myography, which is used less frequently. RNS is easy to apply but not very sensitive. Originally, single fiber myography (sfEMG) was introduced with reusable needles that were specifically designed for that purpose. With the renunciation of reusable material, the technique was applied less frequently. Although a modified version with standard equipment including single use concentric needles is now available, sfEMG did not regain popularity. In this article we present the technical and physiological principles underlying sfEMG and its practical implementation. We show examples of typical reliable waveforms and, in contrast, waveforms that should not be included. Finally, we discuss the reliability of sfEMG results in the clinical context.

Schlüsselwörter

Myasthenia gravis - Elektrophysiologie - Repetitive Nervenstimulation - Einzelfasermyographie - Concentric Needle Jitter

Keywords

Myasthenia gravis - Repetitive Nerve Stimulation - Single Fiber Myography - Concentric Needle Jitter - Electrophysiology

Publication History

Article published online:
01 September 2025

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