Minimally Invasive Approach for the Treatment of Intradural Spinal Pathology

Ravi H. Gandhi, M.D; John W. Germ an, M.D.


Neurosurg Focus. 2013;35(2):e5 

In This Article

Abstract and Introduction


Object A wide variety of spinal intradural pathology traditionally has been treated from a midline posterior laminectomy using standard microsurgical techniques. This approach has been successful in treating the pathology; however, it carries a risk of postoperative complications including CSF leakage, wound infection, and spinal instability. The authors describe a minimally invasive surgical (MIS) approach to treating spinal intradural pathology with a low rate of postoperative complications.

Methods Through a retrospective review of a prospectively collected surgical database, the authors identified 26 patients who underwent 27 surgeries via an MIS approach for intradural pathology of the spine. Using a tubular retractor system and an operative microscope, the authors were able to treat all patients with a unilateral, paramedian, and muscle-splitting technique. They then collected data regarding operative blood loss, length of stay, imaging characteristics, and outcomes.

Results Eight cervical, 8 thoracic, and 11 lumbar intradural pathological entities, which included 14 oncological lesions, 4 Chiari I malformations, 4 arachnoid cysts, 3 tethered cords, 1 syrinx, and 1 chronic visceral pain, were treated via an MIS approach. The average blood loss was 197 ml and the average hospital stay was 3 days. One patient had to return to the operating room for noninfectious wound dehiscence. One patient required reoperation 18 months after the initial surgery for recurrence of the initial pathology. There was no CSF leak, no infection, and no spinal instability associated with the initial surgery on follow-up.

Conclusions Intradural spinal pathology can be safely and effectively treated with MIS approaches without an increased risk of neurological injury. This approach may also offer a reduced postoperative length of stay, risk of CSF leak, and risk of future spinal instability.


Intradural pathology of the spine consists of oncological and nononcological lesions. Either pathology can be divided into intramedullary and extramedullary lesions. The most common intramedullary pathology consists largely of glial tumors, but other neoplasms such as hemangioblastomas, metastatic lesions, and benign pathological processes can be seen. Extramedullary, intradural pathology includes neoplasms (nerve sheath tumors and meningiomas) as well as nononcological lesions such as arachnoid cysts, tethered cord, and syringomyelia.

Clinical presentation can vary widely, ranging from axial or radicular pain to neurological deficits. It is the responsibility of the clinician to elucidate the correlation between imaging findings and symptoms. Advanced imaging techniques such as MRI and CT myelography are invaluable tools in the assessment of these patients and in planning the best management approach.

A midline incision with bilateral muscle dissection, removal of the posterior elements, and wide exposure of the dorsal spinal cord remains the mainstay of treatment. This approach has afforded surgeons access for successful removal of intradural pathology, but there is a risk of CSF leakage, spinal deformity, and postoperative pain. This approach has been modified with hemilaminectomy and partial facetectomy to reduce the risk of postoperative pain and subsequent spinal deformity.[2,7,13]

The use of MIS approaches has been well described for the treatment of degenerative spinal disease. These techniques are now being adopted and modified for the treatment of intradural pathology.[4,12] We elaborate on our experience with MIS approaches in the treatment of various types of intradural pathology and suggest that this technique may contribute to faster postoperative recovery, a lower CSF leakage rate, and a decrease in the risk of spinal instability, by reducing the degree of musculoligamentous disruption.