52. Intraoperative neurophysiology monitoring in lumbar sacral conjoined twins separation

Abstract

Objective Describe the intraoperative neurophysiological monitoring (IOM) used in the separation of two conjoined twins to lumbosacral level. Methods Case report. Six-month-old two twins joined at lumbosacral level, no relevant history or preoperative neurologic deficits. Preoperative magnetic resonance showed fusion of the lumbar-sacral roots. Separation surgery under anesthesia (propofol and fentanyl) was performed. It was recorded with a Cascade Elite, Cadwell, USA; Free run electromyography (EMG) and evoked EMG; transcranial electric motor evoked potentials (tMEP) of the muscles; vastus medialis (VM), tibialis anterior (TA), medial gastrocnemius (MG), extensor hallux (EHA) and anal sphincter bilaterally in both twins. Lower extremities somatosensory evoked potentials in twin 2. Results At baseline the tMEP were evoked: Twin 2 had responses in all muscle, except right TA and GM; twin-1, tMEP only the right GM. During separation, the remaining tMEP were evoked in the twin-1. No neuromiotonic discharges were seen and EMG evoked identified in the twin-1, left EHA and MG left. Postoperatively had no neurological deficit. Conclusions Multimodal MNIO is feasible in separating lumbo-sacral conjoined twins with preservation of neural function. Significance Multimodal MNIO in the separation of lumbo-sacral conjoined twins help to preserve neural function and improve neurological outcome.