Case Study Demonstrating Successful Midline-Sparing Approach for En Bloc Resection of a Ventral Cauda Equina Schwannoma

Introduction: Spinal schwannomas are typically benign, extramedullary masses, but can cause significant neurologic impairment due to mass effect. Resection with open approaches facilitate wide tumor visualization, but minimally invasive approaches can preserve the midline tension band and limit the need for fusion and later adjacent segment disease.

Methods: The patient is a 50-year-old male who presented with six months of subjective lower extremity weakness, numbness, and the sensation of incomplete voiding. MRI showed a 1.7cm ventral, intradural, extramedullary mass at L2/3 level dorsally displacing the cauda equina. Operative management was pursued with a unilateral over the top laminectomy approach, allowing for the preservation of the L2/3 spinous processes and midline ligaments, as well as the bilateral pars interarticularis and facet joints. The patient consented to the procedure and the collection of the operative video. Institutional Review Board (IRB) review was not pursued as a single case study does not qualify as research requiring review.

Results: Despite limited bony resection, the tumor was removed en bloc, and postoperative MRI revealed gross total resection. The patient reported significant resolution of his symptoms including lower extremity weakness and urinary retention and returned to work full-time.

Conclusion : This case demonstrates the practical application of a paramedian, minimally invasive approach for resection of a symptomatic lumbar schwannoma. While there is ongoing debate over the benefits of minimally invasive versus traditional open approaches, this case highlights that the techniques can be used to safely remove moderately large tumors without spinal fusion.