Pre-operative spine tumour embolization: Clinical outcomes and effect of embolization completeness.

INTRODUCTION: To assess the association between the impact of the completeness of pre-operative spine tumour embolisation and clinical outcomes, including estimated blood loss (EBL), neurological status and complications. METHODS: Retrospective chart review of all preoperative spine tumour embolisation procedures performed over 11 years by a single operator (2007-2018) at Vancouver General Hospital on 44 consecutive patients (mean age 57; 77% males) with 46 embolisation procedures, of which surgery was done en bloc in 26 cases and intralesional in the remaining 20. A multivariable negative binomial regression model was fit to examine the association between EBL and surgery type, tumour characteristics, embolisation completeness and operative duration. RESULTS: Among intralesional surgeries, complete versus incomplete embolisation was associated with reduced blood loss (772 vs 1428 mL, P < 0.01). There was no statistically significant difference in neurological outcomes or complications between groups. Highly vascular tumours correlated with greater blood loss than their less vascular counterparts, but tumour location did not have a statistically significant effect. CONCLUSION: This study provides evidence in support of our hypothesis that complete as opposed to incomplete tumour embolisation correlates with reduced blood loss in intralesional surgeries. Randomised control trials with larger samples are necessary to confirm this benefit and to ascertain other potential clinical benefits.

The CT guided transoral approach: A biopsy technique for a poorly differentiated chordoma in a 5 year old.

Mass lesions presenting at the craniocervical junction often present a unique challenge due to the complex anatomic arrangement limiting access for tissue diagnosis. The transoral approach has predominantly been used for percutaneous vertebroplasty of high cervical vertebrae with limited literature describing image guided biopsy for bony lesions in this region in the pediatric patient. We describe a technique of computed tomography guided transoral biopsy of a poorly differentiated chordoma located at the C1-C2 level in a 5-year-old child, and review this diagnosis.

The evolution of pre-operative spine tumour embolization.

Pre-operative spine tumour embolization is a useful adjunct to minimize operative complications and blood loss during complex resections. While the efficacy of this procedure has been well studied, relatively little is documented regarding how to optimize technical parameters for tumour characteristics. This pictorial case series seeks to review our centre's experience over the last decade in using a range of embolization techniques. As experience with this procedure has matured, we propose an approach based on the patient's vascular anatomy and tumour angioarchitecture. This includes the use of coils as protective barriers rather than primary embolics; particle embolization to permeate fine capillary networks; consideration for liquid embolic agents in the presence of large caliber tumour vessels with associated arteriovenous shunting; and percutaneous intralesional embolization when endovascular access is insufficient to achieve the desired outcome. In many cases, a combination of these methods is needed, and close communication with the surgeon ensures the best outcome. Despite these advances, continued work is needed to determine how to optimize complete devascularization, and thus surgical benefit, while safely sparing critical neuroanatomical structures.