Navigated Exoscopic Transtubular Approach for Lumbar Decompression: Surgical Video

Tubular retractors in minimally invasive lumbar stenosis permit surgeons to achieve satisfactory neural decompression while minimizing the morbidity of the surgical access.^1-3 Transtubular lumbar decompression requires intraoperative image guidance and microscopic magnification to achieve precise and reproductible surgical results. Use of 2-dimensional image guidance in transtubular lumbar decompression has a major limitation due to the lack of multiplanar orientation. Consequently, there is a risk of incomplete decompression and excessive bone removal resulting in iatrogenic instability. Furthermore, available microscopes have limited optics (short focal lengths) and unsatisfactory surgeon ergonomics. To overcome these limitations, the authors present a step-by-step video of the navigated exoscopic transtubular approach (NETA) for spinal canal decompression (Video 1). The patient suffers from bilateral L5 radiculopathy due to L4-L5 bilateral synovial cysts responsible for severe L4-L5 canal stenosis. During the entire surgical procedure, NETA implements the use of navigation based on intraoperative 3-dimensional (3D) fluoroscopic images for retractor placement, bone mapping, and neural decompression.⁴ NETA represents a modification of the "standard" MIS transtubular technique for bilateral lumbar decompression. NETA is based on the use of neuronavigation during each surgical step to guide the placement of tubular retractor. This tailors the bone resection to achieve adequate neural decompression while minimizing the risks of potential spine instability. After precise placement of the tubular retractor, bone removal and neural decompression are accomplished under robotic exoscope magnification with 4k 3D images. Using a 3D robotic exoscope (Modus V, Synaptive, Toronto, Canada) allows better tissue magnification and improves surgeon ergonomics during lumbar decompression through tubular retractors.^5,6.