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Study design:
Prospective review of consecutive patients.
Objective:
To evaluate the incidence and raise awareness of electrode discoloration that can occur in the operating room when using neuromonitoring.
Summary of background data:
To our knowledge there are no papers that discuss dermal discolorations following spine surgery.
Methods:
Fo...
Context in source publication
Citations
... For the IONM, we used a pair of needle electrodes (not the standard corkscrew electrodes) applied bilaterally and subcutaneously on the scalp for stimulation purposes, and a single needle electrode at the level of the iliac crest as the ground electrode. Thanks to this choice, we avoided ecchymoses, bruises, and rare infections, which have been reported during IONM [61], as well as reddening of the skin, which was observed in 16% of patients with the accompanying symptom of increased pain, sometimes lasting up to 6 months after the surgery [62], and a significant risk of needle stick injuries by neurophysiologists and other workers in the theater during electrode implantation and their removal after surgery. ...
Introduction: A practical solution to the incidental unreliability of intraoperative neuromonitoring (IONM) may be the simultaneous neurophysiological recording and control of the surgical field through a camera (the concept of “Real-time” IONM). During “Real-time” IONM, the surgeon is immediately warned about the possibility of damage to the neural structures during, but not after, standard idiopathic scoliosis (IS) corrective surgery procedures (the concept of “Surgeon–neurophysiologist” interactive, verbal IONM). This study aimed to compare the advantages, utilities, reliabilities, and time consumption of the two IONM scenarios. Methods: Studies were performed in two similar groups of patients undergoing surgery primarily due to Lenke 2 idiopathic scoliosis (N = 120), when both IONM approaches were applied. Neurophysiological evaluations of the spinal transmission were performed pre- (T0), intra- (before (T1) and after (T2) surgery), and postoperatively (T3), as well as once in healthy volunteers (control, N = 60). Non-invasive and innovative recordings of the motor evoked potentials (MEPs) bilaterally from the peroneal (PER) nerve and tibialis anterior (TA) muscle were performed with surface electrodes as a result of transcranial magnetic stimulation (TMS) or electrical stimulation (TES) at T0–T3. Results: In both groups, the MEP amplitudes and latencies recorded from the PER nerve were approximately 67% lower and 3.1 ms shorter than those recorded from the TA muscle. The MEP recording parameters differed similarly at T0–T3 compared to the control group. In all patients, the MEP parameters induced by TMS (T0) and TES (T1) did not differ. The MEP amplitude parameters recorded from the TA and PER at T1 and T2 indicated a bilateral improvement in the neural spinal conduction due to the surgical intervention. The TMS-induced MEP amplitude at T3 further increased bilaterally. In both IONM groups, an average 51.8 BIS level of anesthesia did not affect the variability in the MEP amplitude, especially in the PER recordings when the applied TES strength was 98.2 mA. The number of fluctuations in the MEP parameters was closely related to the number of warnings from the neurophysiologist during the transpedicular screw implantation, corrective rod implantation, and distraction, derotation, and compression procedures, and it was higher in the “Surgeon–neurophysiologist” IONM group. The average duration of surgery was shorter by approximately one hour in the “Real-time” IONM group. The number of two-way communications between the surgeon and the neurophysiologist and vice versa in the “Real-time” IONM group decreased by approximately half. Conclusions: This study proves the superiority of using “Real-time” IONM over the standard “Surgeon–neurophysiologist” IONM procedure in increasing the safety and non-invasiveness, shortening the time, and lowering the costs of the surgical treatment of IS patients. The modifications of the MEP nerve-conduction-recording technology with surface electrodes from nerves enable precise and reliable information on the pediatric patient’s neurological condition at every stage of the applied surgical procedures, even under conditions of slight fluctuations in anesthesia.
... For IONM, we used a pair of needle electrodes (but not the standard corkscrew electrodes) applied bilaterally subcutaneously on the scalp for stimulation purposes and a single needle electrode at the level of the iliac crest as the ground electrode. Thanks to this choice, we avoided ecchymoses, bruises or rare infections which were reported during IONM [58], reddening of the skin, which was observed in 16% of patients with the accompanying symptom of increased pain, sometimes lasting up to 6 months after the surgery [59], and a significant risk of needle stick injuries by neurophysiologists and other workers in the theatre during electrode implantation and the removal after surgery. ...
The practical problem-solving of incidental unreliability of intraoperative neuromonitoring may be the simultaneous neurophysiological recording and the inspection of the surgical field through the camera (the "Real-time neuromonitoring" concept). This would allow the immediate warning of the surgeon on the possibility of the spinal structures insult during but not after the application of the standard procedures in scoliosis surgery (the “Interactive verbal surgeon-neurophysiologist neuromonitoring" concept). This study aimed to compare the advantages, utility, reliability, and time-consuming of both intraoperative neuromonitoring scenarios using non-invasive and innovative recordings from peroneal nerves (PER) versus tibialis anterior muscles (TA) with surface electrodes of motor evoked potentials (MEP) bilaterally as a result of transcranial magnetic (TMS) or electrical (TES) stimulations. Studies were performed in two similar groups ("Real-time neuromonitoring", N=60 and "Interactive verbal sur-geon-neurophysiologist neuromonitoring", N=60) of patients treated surgically because of mainly Lenke 2 type idiopathic scoliosis (IS) pre- (T0), intra- (T1 – before surgical procedures, T2 – after surgical procedures) and postoperatively (T3) as well as in healthy volunteers (N=60, Control). The cumulative parameters of MEP amplitudes and latencies recorded from PER compared to those recorded from TA in healthy volunteers were approximately 67% (1100µV) lower at p=0.007 and 10.6% shorter (3.1 ms) at p=0.04, respectively. A similar trend was also observed in patients from both groups at each follow-up stage. MEP recordings from TA and PER in patients of both groups differed similarly in T0-T3 compared to controls at p=0.008-0.04. MEP parameters in all patients induced by TMS (T0) and TES (T1) did not differ. The parameters of MEP amplitudes recorded from TA and PER intraoperatively in T1 and T2 differed at p=0.04-0.03, indicating the bilateral improvement of neural spinal conduction due to the surgical intervention. Parameters of TMS-induced MEP amplitudes in T3 further increased bilaterally compared to the tests recorded in T0 at p=0.03-0.02. In both groups of patients, an average 51,8 BIS level of anaesthesia minimally affects the variability of the MEP amplitude, especially in PER recordings when ap-plied TES strength was at 98.2 mA. The number of MEP parameter fluctuations, mainly the amplitudes decreasing, was strictly associated with the neurophysiologist's warnings due to transpedicular screws implantation, corrective rods implantation, distraction, derotation, and compression procedures, respectively; at p=0.04-0.03 more in patients from the “Interactive S-N neuromonitoring” group. The average duration of the surgery was significantly shorter (p=0.04) by about 1 hour in the "Real-time neuromonitoring" group. The number of two-way communications between the surgeon and neurophysiologist and vice versa in the "Real-time neuromonitoring" group was reduced by approximately half at p=0.008. The study's results prove the advantages of using the "Real-time neuromonitoring" procedure in increasing safety and non-invasiveness, shortening the time, and lowering the costs of surgical treatment of patients with pathological lateral curvature of the spine. The modifications of the MEP nerve conduction recording technology with surface electrodes from nerves presented in this study enable precise and reliable information on the patient's neurological condition at every stage of applied surgical procedures, even in conditions of slight fluctuations in the anaesthesia.
... Our previous pilot results on improving the neuromonitoring methodology [32] are fully compatible with their observations. Moreover, taking into account the fact that IS surgeries are pediatric and the consequences of neuromonitoring procedures using TES when MEPs are recorded with needle electrodes can be ecchymosis and bruises associated with the stimulation-related muscle movements, local nerve damage or infections in rare cases [50], and, frequently, postoperative skin reddening [51], recording from the muscle's surface is more beneficial. ...
The relationships between the results of pre- and intraoperative motor evoked potential recordings during neuromonitoring and whether idiopathic scoliosis (IS) surgical correction improves the spinal efferent transmission have not been specified in detail. This study aims to compare the results of surface-recorded electromyography (EMG), electroneurography (ENG, M, and F-waves), and especially motor evoked potential (MEP) recordings from tibialis anterior muscle (TA) bilaterally in 353 girls with right idiopathic scoliosis (types 1–3 according to Lenke classification). It has not yet been documented whether the results of MEP recordings induced by transcranial single magnetic stimulus (TMS, pre- and postoperatively) and trains of electrical stimuli (TES; intraoperatively in T0—before surgery, T1—after pedicle screws implantation, and T2—after scoliosis curvature distraction and derotation following two-rod implantation) can be compared for diagnostic verification of the improvement of spinal cord neural transmission. We attempted to determine whether the constant level of optimal anesthesia during certain surgical steps of scoliosis treatment affects the parameters of MEPs recorded during neuromonitoring procedures. No neurological deficits have been observed postoperatively. The values of amplitudes but not latencies in MEP recordings evoked with TMS in IS patients compared before and after surgery indicated a slight improvement in efferent neural transmission. The results of all neurophysiological studies in IS patients were significantly asymmetrical and recorded worse on the concave side, suggesting greater neurological motor deficits at p = 0.04. The surgeries brought significant improvement (p = 0.04) in the parameters of amplitudes of sEMG recordings; however, the consequences of abnormalities in the activity of TA motor units were still reflected. ENG study results showed the symptoms of the axonal-type injury in peroneal motor fibers improving only on the concave side at p = 0.04, in parallel with F-wave parameters, which suggests that derotation and distraction might result in restoring the proper relations of the lumbar ventral roots in the spinal central canal, resembling their decompression. There were no significant differences detected in the amplitudes or latencies of MEPs induced with TMS or TES when comparing the parameters recorded preoperatively and intraoperatively in T0. The amplitudes of TES-evoked MEPs increased gradually at p = 0.04 in the subsequent periods (T1 and T2) of observation. A reduction in MEP latency at p = 0.05 was observed only at the end of the IS surgery. Studies on the possible connections between the level of anesthesia fluctuations and the required TMS stimulus strength, as well as the MEP amplitude changes measured in T0–T2, revealed a lack of relationships. These might not be the factors influencing the efferent transmission in spinal pathways beside the surgical procedures. Pre- (TMS-evoked) and intraoperative (TES-evoked) recordings are reliable for evaluating the patient’s neurological status before and during surgical scoliosis correction procedures. An increase in MEP amplitude parameters recorded on both sides after scoliosis surgery proves the immediate improvement of the total efferent spinal cord transmission. Considering comparative pre- and postoperative sEMG and ENG recordings, it can be concluded that surgeries might directly result in additional lumbar ventral root decompression. We can conclude that MEP parameter changes are determined by the surgery procedures during neuromonitoring, not the anesthesia conditions if they are kept stable, which influences a decrease in the number of false-positive neuromonitoring warnings.
... Our previous pilot results on improving the neuromonitoring methodology [32] are fully compatible with their observations. Moreover, taking into account the fact that IS surgeries are pediatric and the consequences of neuromonitoring procedures using TES when MEPs are recorded with needle electrodes can be ecchymosis and bruises associated with the stimulation-related muscles movements, rarely the local nerve damage or infections [50], and frequent postoperative skin reddening [51], the recording from the muscle's surface is more beneficial. ...
Neuromonitoring of the efferent nerve impulses transmission in the spinal cord tracts during surgical scoliosis treatment makes it possible to assess whether the functional status is deteriorating, affecting the procedure's safety. Is there any relationship between pre- and intraoperative motor evoked potentials recordings and does idiopathic scoliosis (IS) surgical correction improve directly the spinal efferent transmission? This study aimed to compare the results of surface recorded electromyography (EMG), electroneurography (ENG, M and F-waves), and especially motor evoked potentials (MEP) from tibialis anterior (TA) muscle bilaterally in 353 girls with the right idiopathic scoliosis (types 1A-4C according to Lenke classification). It has not yet been documented whether the results of MEPs recordings induced by transcranial single magnetic stimulus (TMS, pre – and postoperatively) and trains of electrical stimuli (TES; intraoperatively in T0-before surgery, T1 – after pedicle screws implantation, T2 – after scoliosis curvature distraction and derotation following two rods implantation) can be compared for diagnostic verification of improvement of the spinal neural transmission. The study also attempted to determine whether the constant level of optimal anesthesia during the certain surgical steps of scoliosis treatment affects the parameters of MEPs recorded during neuromonitoring procedures. No neurological deficits have been observed postoperatively. Values of amplitudes but not latencies in MEPs recordings evoked with TMS in IS patients compared before and after surgery indicated a slight improvement in the efferent transmission of neural impulses within the fibers of the spinal tracts postoperatively. Results of all neurophysiological studies in IS patients were significantly asymmetrical and recorded worse on the concave side, suggesting greater neurological motor deficits at p=0.04. This asymmetry had been significantly reduced following IS surgery. The surgeries in IS patients brought significant improvement (p=0.04) in parameters of amplitudes of sEMG recordings, however reflecting still the consequences of the neurogenic injury of TA muscle motor units. ENG studies results indicated the symptoms of the axonal type injury in peroneal motor fibers improved only on the concave side at p=0.04 in parallel with the significant improvement of F-waves parameters, which suggests that surgeries might result in the lumbar ventral roots decompression. There were not detected significant differences in amplitudes or latencies of MEPs induced with TMS or TES comparing the parameters recorded preoperatively (one day before surgery) and intraoperatively in T0. The amplitudes of TES evoked MEPs increased gradually at p=0.04 in the subsequent periods (T1 and T2) of observation. The significant reduction of MEPs latency at p=0.05 was observed only at the end of the IS surgery. Studies on the possible connections between the level of anesthesia fluctuations and the required TMS stimulus strength, as well as the MEPs amplitude changes measured in T0-T2 revealed lack of relationships. It is not likely that they could be the factors influencing the efferent transmission in spinal pathways beside the surgical procedures. Considering that MEPs amplitude parameter reflects the number of axons excited from the motor cortex and transmitting the efferent impulses via spinal descending tracts in the white matter, pre- (TMS evoked) and intraoperative (TES evoked) recordings are reliable for evaluating the patient’s neurological status before and during surgical scoliosis correction procedures. The results of this study indicate an agreement between preoperative and early-intraoperative evaluations with these both diagnostic methods. An increase of MEPs amplitude parameters recorded on both sides after scoliosis surgery proves immediate improvement of the total efferent spinal cord transmission. Considering comparative pre- and postoperative sEMG and ENG recordings it can be concluded that surgeries might directly result in the additional lumbar ventral roots decompression. Our results of the tests on the possible variability of the anesthesia level on the parameters of intraoperative recorded MEPs show no clear relationships. We can conclude that MEPs parameters changes are determined by the surgery procedures during neuromonitoring, not the anesthesia conditions if they are kept stable, which influences a decrease in the number of false-positive neuromonitoring warnings. Further studies on a larger population of patients with long-lasting observation postoperatively are required to confirm the presented conclusions on the direct influences of scoliosis surgery on improvement of the motor function in patients with IS.
... Especially in children, in 16% of patients, in whom MEP recordings using needle electrodes were made, reddening of the skin was observed, with the accompanying symptom of increased pain, sometimes lasting up to 6 months after the surgery [10]. ...
Introduction
Motor evoked potentials (MEPs) are currently considered as a more useful method for neurophysi-ological intraoperative monitoring than somatosensory evoked potentials in cases of surgery applied to patients with adolescent idiopathic scoliosis. The non-invasive approach is preferred to modify MEP recordings, criticizing, in many cases, the fundamentalism for neurophysiological monitoring based only on needle recordings. The aim of the review is to provide our own experience and prac-tical guidelines with reference to neuromonitoring innovations.
Material and Methods
Recordings of MEPs with surface electrodes instead of needle electrodes including nerve instead of muscle combinations during neurophysiological monitoring associated with surgical interventions to the spine have become more relevant for pediatric purposes, avoiding the anesthesiology-related influences. Observations on 280 patients with Lenke A–C types of spine curvature are presented before and after the surgical correction.
Results
The MEPs recorded from nerves do not undergo fluctuations at different stages of scoliosis correc-tions and the anesthesia effect more than MEPs recorded from muscles. The use of non-invasive surface electrodes during neuromonitoring for MEP recordings shortens the total time of the surgical procedure without diminishing the precision of the neural transmission evaluation. The quality of MEP recordings during intraoperative neuromonitoring from muscles can be significantly influ-enced by the depth of anesthesia or administration of muscle relaxants but not those recorded from nerves.
Conclusions
The proposed definition of “real-time” neuromonitoring comprises the immediate warning from a neurophysiologist about the changes in a patient’s neurological status during scoliosis surgery (es-pecially during pedicle screws’ implantation, corrective rods’ implantation, correction, distraction and derotation of the spine curvature) exactly during the successive steps of corrective procedures. This is possible due to the simultaneous observation of MEP recordings and a camera image of the surgical field. This procedure clearly increases safety and limits financial claims resulting from possible complications.
... Reported complications of IOM include dermal discoloration and burns, necrotizing fasciitis, and hemorrhage. [6][7][8][9][10] We report a case of upper extremity compartment syndrome as a complication of the use of neuromonitoring needles in a patient receiving dual antiplatelet therapy. The complication occurred after endovascular treatment of a left unruptured supraclinoid internal carotid artery (ICA) aneurysm. ...
... 11 Necrotizing fasciitis and subdermal hemorrhage in the lateral neck region have also been reported. [6][7][8][9][10] Although the benefit of preventing neurologic injury during a neurosurgical procedure greatly outweighs the risk of the rare reported complications related to IOM, it is prudent for caretakers to be aware of these complications so that they can be recognized early and appropriate and effective treatment can be implemented. We present a description of postprocedural compartment syndrome resulting from placement of neuromonitoring needles for routine IOM in a patient receiving dual antiplatelet therapy. ...
Background: The use of intraoperative neurophysiologic monitoring (IOM) has become commonplace in many neurosurgical procedures as a tool to reduce the risk of complications through the early identification of reversible neurologic compromise. Although complications related to IOM itself are exceedingly rare, recognizing their clinical presentation in the postoperative neurosurgical patient is essential for the early identification and implementation of appropriate treatment.
Case Description: The authors present a case report of a patient who developed postoperative acute compartment syndrome in the right arm after placement of neuromonitoring needles for routine IOM during endovascular treatment of a left internal carotid artery aneurysm. Before the procedure, the patient received dual antiplatelet therapy and was noted to have a P2Y12 reaction unit value within therapeutic range. The patient had not received other anticoagulation therapy and had no family or personal history of hematologic or coagulopathic disorders. Immediately after an uncomplicated endovascular intervention, the patient began to develop symptoms of forearm swelling, tightness, and tenderness to palpation; pain with wrist flexion and extension; and paresthesias of the distal digits of the hand. She had eventual loss of a palpable radial pulse. The patient underwent emergent fasciotomies of multiple forearm compartments and had immediate return of a palpable radial pulse.
Conclusions: This case represents the first report of post-procedural compartment syndrome resulting from placement of neuromonitoring needles for routine IOM. Although it is a particularly rare complication of IOM, compartment syndrome represents a surgical emergency that carries significant morbidity if not immediately recognized and treated.
Intraoperative neuromonitoring (IONM) has transformed the fields of pediatric surgery and anesthesia since its introduction in 1979, and is an important diagnostic and preventative tool to potentially decrease neurological complications in children after surgical procedures. Its value in minimizing neurological injury during surgery has been well established in adults, with a 10–30% difference in injury rates in neurosurgical historical cohorts, but this risk reduction has yet to be systematically studied in children. The goal of neuromonitoring during surgery is to detect changes in neural signaling as early as possible, allow surgical teams to prevent further injury by monitoring for and potentially reversing the electrophysiological changes that are detected. The adaptation of various neuromonitoring techniques from the adult population to pediatrics has proved crucial in assessing and optimizing surgical outcomes across numerous subspecialty fields. Early uses of IONM included the use of brainstem auditory evoked potentials (BAERs) and monitoring effects on the spinal cord during spine deformity correction. These early applications demonstrated the powerful utility of IONM and its applicability to children.
