Stimulation Parameters.
- Handheld bipolar electrode probe that should be at 4- 5 millimeter of spacing between the anodal and cathodal tips.
The Ojemann cortical stimulation parameters can be used like.
- 60-Hz pulses, with a 1-millisecond pulse width, beginning at 1 mA. Or what we use train of pulse technique in cranium cases like .
- A train of 5 pulses at the rate of 1-2 Hz .
- Pulse width 1 millisecond .
- ISI 3-3.5 millisecond .
- Intensity of stimulation can begin 0.3 milliampere .
Recording Parameters.
- Motor responses are typically recorded using electromyography [EMG]
- EMG electrodes to be placed on the patient’s limbs to record muscular responses to the electrical stimulation.
- Recording site .abductor pollicis brevis-flexor digiti minimi brevis or extra muscle channel can be added as per requirement [upper extremity].
- Tibialis anterior-gastrocnemius, and abductor halluces-abductor digiti minimi for lower extremity extra channel as per requirement
- The goal of recording EMG activity from these muscle groups it increases the sensitivity of eliciting activity from those axons that are encoded for activating fine motor movements {i.e.,
- corticospinal} Rest of proximal muscle of limbs and thoracic innervated myotome will be preferred to assess the other fibers function like rubrospinal tectospinal etc .
Conclusion .
Above given parameters can be modified as per clinician and institute.
Related to this article.
https://neurointraoperative.com/wp-admin/post.php?post=1808&action=edit
https://thejns.org/spine/view/journals/j-neurosurg-spine/22/2/article-p205.xml
Question.
What is the meaning of cord mapping?.
Train of five pulses are useful?.
Which myotomes to be monitored?.
Muscle relaxant can interfere with this?.
2 thoughts on “Stimulating and Recording Parameters of direct cord stimulation in intramedullary spine tumors.”