Introduction: Spinal intradural lesions have been classically treated using an open posterior translaminar approach, regardless of lesion localisation with respect to the spinal cord. This "one size fits all" strategy works for many lesions, but is very limiting for others, particularly ventrally located lesions. Minimally invasive (MISS) techniques facilitate flexibility in approach trajectories of close to 180° from side to side, while allowing for standard microsurgical techniques intradurally. These approaches reduce the extent of muscle dissection and of blood loss.
Methods: Retrospective patient record review from 2004-2013. Inclusion criteria include intradural spinal pathologies treated using the minimal access (MISS) techniques. We present clinical and radiological follow up.
Results: 38 cases performed in 37 patients. 3 were excluded (2 with follow up outside country, 1 lost to F/U locally).
35 cases included (34 patients, 18 male and 16 female) Ave age 50.4 yrs (20-80).
7 cases were cervical, 12 thoracic, and 16 lumbosacral. Extramedullary pathologies: meningioma 8, schwannoma 12, arachnoid cyst 3, primary myxopapillary ependymoma (MPE) 3, secondary MPE 2, neurofibroma 2.
Intramedullary pathologies: C2 cavernoma 1, C2 anaplastic astrocytoma (AA) 1, C4 teratoma 1, T10 schwannoma 1, T12 hemangioblastoma 1.
Mean follow up was 23.5 months (2-67).
Postoperative MRI (all cases): progressive AA 1 (chemotherapy), recurrent meningioma 1 (fractionated radiotherapy), residual tumor 2 (intramedullary teratoma, meningioma adherent to ant spinal artery). 2 patients with drop mets from MPE stable at 8 and 43 months after surgery. Remainder confirmed gross total resection of the tumor.
Clinical complications (4 cases) -partial hemisensory loss (C2 AA) -min gait imbalance (C2 cavernoma) -Persistent S2 sensory loss (S2 schwannoma), seroma (drained)
Conclusions: 1) MISS techniques appears to be a safe alternative to standard open approaches for intradural extramedullary and highly selective intramedullary lesions.
2)Standard microsurgical techniques can be used intradurally.
3) More flexible approach trajectory may enhance resection
Patient Care: MISS techniques may diminish approach related morbidity, while not compromising and possibly enhancing of quality of lesion resection.
Learning Objectives: By the conclusion of this session, participants will be able to
1) discuss the role of MISS techniques as an alternative to standard open approaches for intradural spinal pathogies.
2) realise the standard microsurgical techniques can still be used for lesion resection.
3) discuss the potential advantages of such an approach such as a more favorable trajectory for certain lesions (especially ventrally placed ones), less muscle dissection, low blood loss.