Neuromonitoring
Under Neuromonitoring refers to the visual and audible representation of the neurophysiological activity of one or more nerves . With the help of intraoperative neuromonitoring, surgeons have constant control over nerve tracts that are at risk from an operative intervention . Nerves that are not clearly visible macroscopically can be identified using neuromonitoring. The first application in humans was published by Flisberg in 1969 .
Working principle
The manipulation of a motor peripheral nerve leads to the release of action potentials , which in turn lead to the contraction of the muscle supplied by this nerve . These contractions are identified, electronically amplified and acoustically via a loudspeaker and / or visually on a display ( electromyographic recording ) using fine electrodes inserted into the muscle or muscles . Alternatively, the nerve can also be stimulated directly with a probe with a tiny current surge (0.2 mA to 2 mA), which in the case of intact nerves also leads to muscle contraction. The signal emitted is directly proportional to the intensity of the nerve stimulation.
Areas of application
The use of neuromonitoring is sensible in operations if, due to the anatomical complexity of the operating area or irregular anatomical conditions, it appears possible to injure a certain motor nerve. Irregular conditions can occur in particular in recurrence operations , in areas of scarring or in the area of tumors.
Examples
- Monitoring of the facial nerve during resection of the acoustic neurinoma , ear surgery and interventions on the parotid gland .
- Monitoring of the nerves of the brachial plexus during neurosurgical operations in this area or trauma surgery (especially the radial nerve on the upper arm).
- Monitoring of the recurrent laryngeal nerve during operations on the thyroid gland ( goiter resection , thyroidectomy ): The target muscles here are the vocal cord muscles. The variability of the course and the often difficult visualization of the nerve, which is only approx. 1 mm thick, make neuromonitoring indispensable, especially in operations for thyroid carcinoma and recurrent goiter. Continuous intraoperative neuromonitoring is a further development in this field .
swell
- ↑ K. Flisberg, T. Lindholm: Electrical stimulation of the human recurrent laryngeal nerve during thyroid operation. In: Acta Otolaryngol Suppl. 263, 1969, pp. 63-67. PMID 5269062
- ↑ a b Wolfgang Timmermann, Wulf Heinrich Hamelmann, Arnulf Thiede: Thyroid surgery: Neuromonitoring to protect the recurrent nerve. In: Deutsches Ärzteblatt . 101, 2004, p. A 1341-1345 [issue 19]