Description
This presentation focuses on the topic of dorsal column identification using Intraoperative Electrophysiological Monitoring (IEOM). The speaker starts by explaining the rarity of these techniques in clinical routine, which often require specific technologies and methods typically employed in neuromonitoring. The motivation behind this topic is highlighted, particularly in the context of tumor growth that causes anatomical distortion, leading to risks of dorsal column injury and potential postoperative deficits for patients.
The speaker discusses different methods of surgical access to the spinal cord, detailing lateral, dorsal root entry zone, and midline approaches, with midline entry being the most commonly used due to its safety. Identifying the midline presents challenges, especially in cases of edema or spinal cord rotation, thus necessitating the use of electrophysiological mapping methods to accurately locate it.
Two sensory mapping techniques based on Somatosensory Evoked Potentials (SSPs) are presented. The first involves direct spinal SSP recording and stimulation of peripheral sensory nerves using a mini multi-channel electrode placed on the spinal cord, while the second involves standard recordings from scalp electrodes where stimulation is applied directly in the surgical field. Both methods seek to identify the midline through observing amplitude responses, highlighting their advantages and limitations.
The speaker emphasizes the lack of extensive clinical data regarding these techniques but references a retrospective cohort study indicating improved postoperative outcomes for patients undergoing dorsal column mapping. Ultimately, the speaker summarizes the significance of midline identification methods in enhancing surgical outcomes and advocates for their use despite not being routine practice, suggesting that they can be effectively integrated into existing procedures.