gms | German Medical Science

Objective: Both neuromonitoring and early magnetic resonance imaging (MRI) provide crucial information for treatment management and prognosis in patients with severe traumatic brain injury (sTBI). Yet, many neuromonitoring devices are restricted in MRI examinations due to MRI safety concerns, possibly causing thermal brain tissue damage. So far, neuromonitoring in situ impedes the routine implementation of MRI, potentially resulting in missing relevant data. The aim of the study was to evaluate the brain tissue damage induced by inserted neuromonitoring devices and its clinical relevance.

Methods: Nineteen patients with sTBI admitted to our neurosurgical ICU from 03/ 2015 to 12/2017 and being exposed to at least one MRI with neuromonitoring in situ and one follow-up MRI after neuromonitoring removal were prospectively included in the study. All MRIs were reviewed for specific tissue damage caused by the probes. Outcome was assessed 6 months after sTBI.

Results: Three females and 16 males (aged 20–74 years, mean 42.8years) with an initial median GCS of 5 (range 3-8) were analyzed. No lesion was observed in 6 patients (31.6%), whereas another 6 patients (31.6 %) demonstrated a detectable probe trajectory. Probe-related brain tissue damage was visible in 7 patients (36.8%) with the size of the lesion prone to enlarge more with increasing numbers of MRI examinations. Upon interdisciplinary evaluation the lesions were not considered clinically relevant.

Conclusion: Neuromonitoring probes in situ during MRI examinations may cause local brain tissue damage, yet without any clinical implications. For this reason, indications must be strictly based on joint decision from all involved disciplines, ideally obeying institutional standard operating procedures. Yet, neuromonitoring in situ should not be a reason to disqualify patients from MRI examinations in the early phase after sTBI. The size of neuromonitoring-induced brain damage appears commensurate with the time of examination.