1 Myxopapillary ependymoma. neurophysiological monitoring

About Myxopapillary ependymoma?.

A rare type of ependymal tumor {Myxopapillary ependymoma} , this form of pathology primarily affects the spinal cord, particularly in the filum Terminale and conus medullaris regions.

Characteristics.

As per histopathology ME form of tumors are characterized by a mix of papillary structures and a myxoid (gelatinous) background.

As per Demographics data- This is more commonly seen in young adults, although it can occur in individuals of any age.

Clinical complains.

Complains/Symptoms. Subjects usually present with symptoms related to spinal cord compression, including low back pain{LBP}, motor weakness, sensory loss , and bladder or bowel dysfunction.{ Depend on severity}.

Tumor location. These type of tumors are usually found at the lower end of the spinal cord, which may contribute to specific neurological deficits depending on their size and extent. This type of cases can be confirm through routine MRI study.

Scan.  Myxopapillary ependymoma.

Why we do intraoperative neurophysiological monitoring {IONM} and what kind of specific modality is useful ?.

Real time neurophysiological-monitoring{RTNM}.

As we know perioperative neurophysiological monitoring modalities like motor evoked potential , somatosensory evoked potentials these technique help to monitor of functional integrity of spinal cord and peripheral nerve roots .

But Triggered Electromyogram technique/modality plays very specific role while resecting the ependymal tumor {Myxopapillary ependymoma}.compare among modalities{MEP,SSEP}.

Role of specific technique{ Triggered Electromyogram}?.

As we know the form of tumor arising from lower end of cord ,conus level, and here all major nerve roots motor/sensory which innervates our lower extremities, along with bowel and bladder from lower sacral region , while stimulation being performed {Triggered electromyogram} it gives real time information about functional individual motor nerve roots , if functional sensory nerve roots comes in surgical field while resecting the tumor that also con be confirmed through this technique its call high frequency stimulation to see the reflex arc. Through these technique can be preserved the function of motor and sensory nerves, which is play important role of our daily life.

Role of  MEP and SSEP . {Myxopapillary ependymoma}.

these type of ependymal tumors can cause neurological deficits through compression or invasion, real-time neurophysiological monitoring is crucial. It allows for the early detection during perioperative period.

As per multimodality technique is always useful but here describing the importance of each modality like MEP,SSEP,TEMG, Pudendal nerve SEPs intraoperative period while separating/ resecting the tumor TEMG frequently we use to see the filum terminal and individual nerve roots.

MEP+SSEP also gives real time information {gross conduction} about continuity/integrity of nerve roots and cord. the clinical utility of SEPs is limited in Filum Terminale FT surgery compared with triggered EMG and transcranial motor evoked potentials .

Limitation of SSEPs in Filum Terminale {FT} surgery.

By conventional SEPs from posterior tibial nerve of the lower extremity do not cover all the root levels at risk, and the change in SEPs cannot be immediately recognized {as SEPs are averaged responses, and there is always a time lag}.

Pudendal nerve sensory evoked potentials (PSEPs) – Is useful in this surgical procedure.

D wave is useful in this type of surgery?. Myxopapillary ependymoma.

Here no role of D wave because surgeon working on conus level means there is no cord ,D wave potential/signals of corticospinal tract .

Anesthetic Considerations.

The choice of anesthetic drugs are critical, as some can adversely affect the quality of neurophysiological monitoring signals.

Choice of drugs to assess the function of each modalities- Fentanyl/Remifentanil Along with Propofol.

Core Temperature should be maintained at least 35-36 degree Celsius -MAP 65-75mmHg.

Inhalational agents usually not preferable like N2O desflurane, sevoflurane, isoflurane because these drugs half life more compare TIVA and also act on NMJs because it contains some muscle relaxant properties.

Real time neurophysiological-monitoring {RTNM} is essential to preserve neurological function from deficits in surgeries involving myxopapillary ependymomas at the conus medullaris. As i described the importance of modalities each modality has own advantages and disadvantages so here multimodal techniques are always preferable compare single one. As well as anesthetist plays very much important role specially complex type of spinal tumors surgery.

Is there intramedullary spine tumor surgery are safe under Intraoperative Neurophysiological Monitoring (IONM)?